During the last two decades, there have been significant strides in the diagnosis of soft tissue tumors, including identification of various tumor entities, newer immunohistochemical markers, and an increasing number of molecular signatures, defining certain tumors. Lately, there are certain emerging tumor entities, defined by their molecular features with an impact on treatment. At the same time, there is a certain degree of overlap in the expression of certain immunohistochemical antibody markers, as well as genetic markers, with certain gene rearrangements and chimeric fusions observed among completely different tumors. Moreover, a certain amount of clinicopathological, immunohistochemical, and molecular proximity has been unraveled among certain tumor types. Over the years, the World Health Organization (WHO) fascicles on tumors of soft tissue have succinctly brought out these aspects. The present review describes recent updates in the diagnosis of soft tissue tumors, including certain newly described tumor entities; emphasizing upon newer, specific immunohistochemical and molecular markers, along with concepts, regarding “intertumor relationships”.

Background: In core needle biopsy (CNB) often the histological grade of invasive breast carcinoma is under-estimated due to heterogeneity of epithelial component. Stroma is relatively homogenous throughout the tumor and strong CD10 stromal positivity is proposed to be associated with high tumor grade. Aims and Objectives: The aim of this work was to study the expression of CD10 in stromal cells of invasive carcinoma of breast, no specific type (NST) in CNB specimens, and analyze its association with final histological grade and lymphovascular invasion (LVI). Materials and Methods:A total of 50 cases of invasive carcinoma of breast, NST were studied for 18 months. CNB specimens were graded according to modified Scarff–Bloom–Richardson (SBR) system and CD10 positivity was assessed in stromal cells. Mastectomy specimens were also similarly graded. Relation of stromal CD10 positivity with histological grading and LVI was studied. Statistics: Associations between the variables were studied by Chi-square test. A value of P < 0.05 was considered to be statistically significant. Results:On CNB 46% patients had a grade 2 tumor, followed by 30% grade 3 and 24% grade 1 tumor. Strong CD10 positivity was seen in 40% cases, 32% showed weak positivity and 28% were negative for CD10 in stromal cells in CNB specimen. On evaluation of mastectomy specimen 48% of the patients had a grade 2 tumor, followed by 40% grade 3 tumor and 12% grade 1 tumor. Strong CD10 positivity was found to be significantly associated with final grade 3 tumor (P < 0.001) and LVI (P = 0.005). Conclusions: There was underestimation of histological grade on CNB, while strong stromal CD10 positivity in CNB was significantly associated with final grade 3 tumor and LVI.

Background: Atrial fibrillation(AF) is as an abnormal irregular rhythm with chaotic generation of electrical signals in the atria of the heart. Various studies in the West have proved that atrial substrates, like isolated atrial amyloidosis can trigger the development of atrial fibrillation. In India, these structural changes have been analyzed on autopsied hearts. Aim: To determine the role of Atrial Amyloid as a substrate for Atrial fibrillation in ante mortem hearts. Methods and Results: Atrial appendages were obtained from seventy five patients undergoing open heart surgery at a tertiary care hospital in south India. They were stained with Hematoxylin &Eosin, Masson's Trichrome and Congo red stains and were examined for myocarditis, fibrosis and amyloidosis, respectively. 30 (40%) patients were in AF. Amyloid deposits were seen in 3 cases. All the three were in AF and had undergone mitral valve replacement (MVR) (P<0.05). 2 out of the 3 amyloid-positive cases showed active myocarditis and severe scarring but there was no statistically significant correlation between these factors. Conclusion: Amyloid and myocarditis, independently act as an arrythmogenic substrates in the development of atrial fibrillation and are also increasingly associated with female gender and MVR. We hypothesize that the amyloid deposits are due to isolated atrial amyloidosis as they were seen only in young individuals. Some patients in sinus rhythm (SR) had large left atria and myocarditis and probably are at a higher risk for developing AF. Hence, follow-up of these patients is required for prevention of severe organ damage and timely therapeutic intervention.

Background: Cardiac myxomas (CMs) are the most common primary tumors of the heart, said to be derived from pluripotent cardiac stem cells. They are most often attached to the left side of the inter-atrial septum (IAS) and a feature noted at the site of attachment is a conglomeration of thick-walled vessels that has been noted to precede the development of myxomas. Aims:The present study was conducted to compare histology of the normal inter-atrial septa to the septal flap excised with the myxomas and to evaluate the significance of this 'vascular tangle' in the histogenesis of these tumors. Materials and Methods:In a 10-year retrospective analysis of all surgically excised CMs, tumors with attached septal sleeves were selected. This histology was compared to the serial sections of 25 normal age-matched septa obtained from normal hearts at autopsy. Results:Of the 56 myxomas seen in 10 years, 38 tumors (all left atrial in location) were received with a flap of the IAS. All of these cases, irrespective of the sizes of the tumor, showed the presence of conglomeration of thick-walled blood vessels, many of which showed abrupt myxoid change in their walls. Another noteworthy feature in many vessels in all flaps was migration of the myxoid tissue through the vascular walls and the endocardium to mushroom out into the atrial lumen. Such vascular channels were not seen in any of the normal IAS. Conclusions:Based on these findings, we propose a two-step hypothesis: an initial step that stimulates the pluripotent cells toward vasculogenesis with endothelial and smooth muscle differentiation, and a subsequent step leads to production of abundant mucopolysaccharides that splay apart the smooth muscle cells, which would explain rings, cords or nests of myxoma cells around endothelial lined spaces.

Context: Role of cancer stem cells in the esophageal carcinogenesis is not clear. Aim:To assess the expression of CD44 and CD133 cancer stem cell markers in esophageal squamous cell carcinoma (ESCC) and its predisposing lesions by immunohistochemistry. Setting and Design:Prospective study as a part of an intramural research project. Materials and Methods:Tissues samples were obtained with endoscopic biopsy and from surgically resected esophageal specimens. Fifty cases each of histopathologically diagnosed cases of esophageal squamous cell carcinoma and its predisposing lesions (mild, moderate, and severe dysplasia and esophagitis) were evaluated for stem cell marker CD44 and C133 by immunohistochemistry using a scoring system. Statistical Analysis:Chi-square test, analysis of variance (ANOVA), post-hoc tests (Tukey-HSD) were used as appropriate for data analysis. Two sided P < 0.05 was considered as significant. Results:CD44 expression was significantly higher in ESCC as compared to dysplasia and esophagitis (mean IS 7.92 ± 1.45 vs. 6.34 ± 0.80 vs 5.15 ± 0.86 respectively, P < 0.001). CD133 expression was also significantly higher in ESCC as compared to dysplasia (mean IS 6.82 ± 1.57 vs. 1.00 ± 0.00 respectively, P < 0.001) while esophagitis showed no expression. CD44 and CD133 expressions were significantly higher in poorly differentiated ESCC than moderately differentiated and well differentiated lesions (CD44 mean IS 6.94 ± 1.44 vs 8.17 ± 1.38 vs. 8.63 ± 1.02 respectively, P < 0.001 and CD 133 mean IRS 5.63 ± 0.81 vs 6.00 ± 00 vs. 9.0 ± 00 respectively, P < 0.001). Conclusion:Significantly higher expression of CD44 and CD133 cancer stem cell markers in ESCC as compared to its predisposing lesions (esophagitis and dysplasia) suggests its role in esophageal carcinogenesis.

Aim: The present study evaluates the prognostic significance of perineural invasion (PNI) on 2-year, 5-year, and overall survival in patients undergoing gastrectomy and D2 lymphadenectomy due to locally advanced gastric cancer. Materials and Methods: Included in the study were 231 patients who underwent surgery between November 2006 and October 2018 due to stage 1B and over locally advanced gastric cancer, whose records were reviewed retrospectively. Statistical Analysis: The variables in the presence or absence of PNI were compared between the two groups with a Chi-square test, a Fisher's exact test, a likelihood ratio, and a Mann–Whitney U test. Overall survival data were evaluated with a Kaplan–Meier test. Prognostic factors were evaluated with a stepwise Cox regression analysis. Results: PNI was identified in 167 (72.3%) of the patients. The 2-year, 5-year, and overall survival rates at the end of the follow-up period were 85.9%, 70.3%, and 64.1% in those without PNI, and 52.7%, 38.3%, and 36.5% in those with PNI, respectively. In a multivariate analysis, PNI appeared to be a significant prognostic factor for 2-year survival (P = 0.04) but had no effect on 5-year and overall survival. Conclusions: Survival was shorter in patients with PNI than in patients without PNI, and PNI had no effect on overall survival, although it was found to be of prognostic significance for 2-year survival.

Background and Aims: An early correct diagnosis of celiac disease (CD) is fundamental to reversal of symptoms and prevention of complications in pediatric patients. Our aim was to evaluate the role of duodenal bulb biopsy by studying the degree of mucosal damage in the duodenal bulb (D1) and second part of the duodenum (D2) and correlating the findings with serum IgA anti-tTG levels. Settings and Design: Pediatric patients (age <18 years) with clinical suspicion of CD and positive IgA anti-tTG titers were consecutively enrolled over a period of one year. Demographic variables, anthropometry, clinical history, laboratory values and endoscopic findings were studied. Endoscopic biopsies obtained from D1 and D2 were evaluated and assigned histopathologic grades that were correlated with serology. Statistical Analysis Used: Descriptive statistics were employed. Results: A total of 37 clinically suspected cases of pediatric CD were studied. The mean age was 6.7 years and the M:F ratio was 1:1.3. Thirty-two (32) children had varying degrees of growth impairment. Eight (8) children had only extra-intestinal symptoms. Thirty (30) children were anemic, hypoalbuminemia was seen in five (5) children while transaminitis was seen in two (2) children. IgA anti-tTG >300 U/ml was associated with Marsh-Oberhuber Grade 3 morphology at atleast one site. Conclusions: Low positive serology values should be confirmed by histopathology. Biopsies should be taken even in the absence of endoscopic abnormality. Additional D1 biopsies placed in a separate container can increase the diagnostic yield.

Context: Programmed cell death ligand-1 (PD-L1) is the key inhibitor of the cytotoxic immune response thus causing progression of tumors and adverse prognosis in many malignancies. Objective: The current study investigates PD-L1 expression in colorectal carcinoma and its correlation with clinicopathological parameters, microsatellite instability, and BRAF mutation. Material and Methods: 110 cases of colorectal carcinoma were evaluated for PD-L1 expression using SP263 clone in tissue microarray. Clinico-pathological characteristics and survival data were correlated with PD-L1 expression analyzed at different cut-offs of ≥1%, ≥10% and ≥50% in tumor cells and tumor infiltrating lymphocytes along with its correlation with BRAF expression and microsatellite instability status in these cases. Results: Mean age was 49 years with male to female ratio of 1.5:1. 52.7% cases presented with stage 3/4 disease and 14.7% with >10 cm tumor size. Tumor cells expressed PD-L1 in 40% and TILs in 45.4% cases at a cut off of ≥1% was 17.3%, at ≥10% was 15.5% and at ≥50% was 7.3%. Significant association was seen between tumor proportion score (TPS) and increasing age, histological type, histological grade, tumor size, higher T stage (p = 0.03), TILs (p = 0.04), lymph vascular invasion, and perineural invasion. PDL-1 correlated with BRAF expression and microsatellite instability (MLH-1/PMS-2 expression loss). The overall survival was significantly higher (p < 0.001) with negative PDL1 expression in cases of colorectal carcinoma. Conclusions: Immunotherapy may be used as potential therapeutic option in colorectal carcinoma cases showing microsatellite instability and BRAF mutations which show poor response to conventional chemotherapy regimen and anti-EGFR therapy.

Background: Crescentic glomerulonephritis (Cr GN) is pattern of glomerular injury resulting from wide range of diseases sharing a common pathogenesis. Objectives: The objective of our study was to analyze the clinicopathological spectrum and outcome of Cr GN with special reference to its immunopathological subtypes using a panel of immunofluorescence stains. Materials and Methods: Native renal biopsies with crescentic pattern of injury were included. Detailed Clinical and laboratory variables were analyzed along with the treatment protocol and renal outcome, wherever available. Renal biopsy slides were evaluated for various glomerular and extraglomerular features. Both qualitative and quantitative data were analyzed. Results: A total of 57 cases of Cr GN were included; majority (47.36%) of cases were pauci-immune in nature. Among clinical features, ranges of proteinuria and creatinine level were significantly different between subgroups. The various light microscopic parameters, including proportion of cellular crescents and capillary wall necrosis were different. Presence of arteriolar changes also showed association with unfavorable outcome. Three unusual associations, including IgA nephropathy, membranous glomerulonephritis and Hepatitis B infection were detected. Adequate follow-up information was available in 35 of the patients. Of these, 14 were dialysis-dependent at the last follow-up. Conclusions: Type III Cr GN (pauci-immune Cr GN) was the commonest cause of Cr GN in our population. Adult patients required renal replacement therapy more frequently than pediatric cases those are chiefly infection associated. Critical appraisal of clinical, histopathological and immunofluorescence finding help to identify individual subtypes as treatment and outcome varies accordingly.

Background: Adenine phosphoribosyltransferase (APRT) enzyme deficiency is a rare autosomal recessive disorder of purine metabolism affecting mainly the kidneys. It can present at any age with varying degrees of acute and chronic renal damage. Though xanthine dehydrogenase inhibitors offer effective control over the disease process, delay in diagnosis and treatment often lead to compromised function of native and even graft kidneys. Methods: We have done a retrospective search of records of renal biopsies reported at our center during the 5-year period from 2014 to 2018 to identify biopsies with 2,8-dihydroxyadenine crystal deposits. The demographic, clinical, and histopathological findings in these cases were studied and reviewed in the light of available literature. Results: Of 9059 renal biopsies received during the study period, 3 cases had the rare 2,8- dihydroxyadenine (DHA) crystals. All of them were diagnosed for the first time on allograft biopsies. Conclusion: A high index of clinical suspicion together with the characteristic microscopic appearance of crystals on renal biopsy and urine microscopy can clinch the diagnosis of this rare disease. Hence, improving awareness about this entity among clinicians and pathologists is extremely important.

Introduction:Blistering or vesiculobullous disorders in pediatric population are either immunobullous or mechanobullous. Spectrum was analyzed using demographic details, clinical features, histopathology, direct immunofluorescence (DIF) and Immunofluorescence mapping (IFM). Methodology:This was a single institution based observational study in children below 18 years. The demographic details were collected using proforma containing particulars of the patient, history, complaints, and other parameters. Punch biopsy of the skin lesion was done. Biopsy samples were examined under light microscope followed by DIF using fluorescent conjugated polyclonal antibody against immunoglobulins IgG, IgM, IgA, and complement C3. The salt-split technique was also used in particular cases. IFM was done using anticytokeratin (CK) 5 & 14, antilaminin 332, anticollagen VII, and anticollagen IV antibodies. Results:Out of total 50 cases, linear IgA bullous dermatosis (LABD) was the commonest. The average concordance between clinical and final diagnosis (histopathological examination + DIF) was 87.5% and discordance was 12.5%. The agreement between histopathological examination and DIF was found to be substantially significant (κ = 0.6892). IFM depicted epidermolysis bullosa simplex with reduced CK 14 expression, dystrophic epidermolysis bullosa with reduced Collagen VII expression and junctional epidermolysis bullosa with absent laminin 5 expression. Conclusion:The spectrum of bullous lesions in childhood was properly delineated and subcategorization of EB was done. Histopathological examination showed the hallmarks that were conclusive in most of the cases except in LABD and EB. DIF and IFM proved indispensable in those cases. Thus, DIF is not a substitute for histopathology but complementary to it.

Background: HPLC is one of the most important tools for accurate diagnosis of hemoglobinopathies and thalassemias. The advantage of the HPLC system is the excellent resolution, reproducibility &quantification of several normal and abnormal hemoglobin. Results: BIO RAD Variant II analyzer was used. Sickle cell syndromes including double heterozygous states accounted for 56.13% of total cases. HbSS, HbS/β⁰-th, HbS/β⁺–th β-thal trait comprises 29%, 6.5%, 5.1%& 10% of total cases respectively with mean MCV (fl) = 84, 68,71,64 respectively. The Mean HbA2 for β-thal trait, HbE trait &HbE-β thal showed 5.1 ± 1.1, 19 ± 9 & 24 ± 8 respectively. HbF is increased in 8.6% case (excluding SC syndromes & β-thal disorders), of these 5.5% were infants & 12 cases of Aplastic Anemias. Peak P2 >7% (2.4% cases) was seen in uncontrolled diabetes mellitus which on quantification showed HbA1C = 8 ± 2.1 mmol/L. Discussion: HPLC in correlation with CBC parameters & family studies can aid in the diagnosis of majority of Hemoglobinopathies and thalassemic syndrome. The CBC & HPLC parameters of the present study are in good correlation with the research conducted by Tejinder Sing, RiouJ & Alla Joutovsky. Present study showed HPLC comprehensively characterizing HbS, A, A2, F, S, C, D from each other & was also applicable for the quantification of HbA1c for the monitoring of Diabetes Mellitus. Conclusion: The merits of HPLC are small quantity of sample required, economical, less TAT, accurate categorization of HbS, HbA2 & F. But one has to be aware of the limitations and problems associated with this method due to variant hemoglobin within the same retention windows. The present findings show HPLC as an excellent & powerful diagnostic tool for the direct identification of hemoglobin variants with a high degree of precision in the quantification of normal and abnormal hemoglobin fractions.

Background: The COVID-19 pandemic lockdown has forced university hospitals to forego traditional classes and embrace online teaching platforms as the sole modality of medical education. Herein, we describe our experience of shifting from the arena of a real to a virtual classroom during the lockdown phase. Materials and Methods: The institutional subscription of G-suite was used for creating a virtual Google classroom. Google Calendar, Google Meet, and Google Forms were used for notification of schedules, conducting theory and practical classes, and conducting assessments, respectively. The learner-centric SNAPPS model was adapted for an interactive case-based learning (CBL) program using multimedia tools. Students' perspective on online education was assessed based on their responses to a validated questionnaire. Results: The conduction of online classes, particularly the live practical classes and the CBL program got the maximum affirmative (up to 85%) responses. Students of the same batch also performed better in a test following the online CBL (77.03% vs 73.3%, P = 0.03, paired t-test statistically significant) compared to a test before it. However, access to laptops and poor Internet connectivity were significant causes of concern for nearly 40% of students. Conclusion: The use of virtual classroom has proved to be an efficient method for continuing teaching of Pathology to MBBS students in times of lockdown when face-to-face conventional teaching was not possible. The experience indicated that in the future a judicious mixture of traditional and online classes may be a more effective educational design for teaching Pathology to MBBS students.

Sertoli-Leydig Cell Tumors (SLCT) are very rare neoplasms of the ovary (0.2%) and they belong to the group of sex cord-stromal tumors. Of these, 20% of the cases show heterologous elements. We report a case of a 22-year-old woman who presented with complaints of lower abdominal pain and secondary amenorrhea for 10 months. Physical examination revealed right lower abdominal tenderness and fullness. Imaging showed a right ovarian mass. She underwent right salpingo-oophorectomy with bilateral pelvic lymphadenectomy and omentectomy. Microscopic examination revealed a neoplasm with varied histomorphological patterns. The predominant pattern was an atypical proliferative mucinous tumor with foci of microinvasion. The other component was that of moderately differentiated Sertoli-Leydig Cell Tumor. Focal areas resembling carcinoid were also noted. Immunohistochemistry was performed and the Sertoli-Leydig Cells were positive for CD56, calretinin, inhibin, vimentin, and ER. The glandular component was positive for CK20, EMA, CEA, and CDX2. Synaptophysin and chromogranin were positive within nests resembling carcinoid. With the given histomorphological features and immunohistochemistry findings, a diagnosis of moderately differentiated Sertoli-Leydig Cell Tumor of the ovary with associated mucinous carcinoma and carcinoid was rendered. The presence of heterologous elements in SLCTs has been reported to be associated with poor prognosis.

Background: Condylomata acuminata, commonly known as genital wart is a sexually transmitted disease caused by Human Papillomavirus (HPV). The positivity of HPV6/11 in condylomata acuminata in western literature varies from 80-90% however, there is a paucity of Indian literature. Aim: The aim of the present study was to determine the role of HPV 6 & 11 in Condylomata acuminata in Indian patients. Methods: A total of 22 formalin fixed parafilm embedded (FFPE) tissue was collected from the cases of condylomata acuminata which was histologically diagnosed and was used to detect HPV 6 and 11 by PCR. Results:Of these 14/22 patients (63.6%) were positive for HPV 6 or 11; HPV 6 alone in eight (36.3%) and HPV 11 in six (27.2%). Conclusion: The high HPV 6 and 11 PCR positivity suggests their definitive role in causation of condylomas cases. This important HPV infection is preventable by prophylactic vaccination.

Melanomas within the Central Nervous System (CNS) are most commonly metastatic lesions, with primary melanomas comprising only 0.05–0.07% of all brain tumors. We report three cases of primary CNS melanoma. The patients were young adults. There were two females and one male. On preoperative investigations, two cases were misdiagnosed to be angiomas on Magnetic Resonance Imaging (MRI). The melanotic nature of the lesion was an intraoperative observation. Pathologic examination showed features of malignancy with invasion of tumor cells into the brain parenchyma. In two patients, presence of systemic lesions were ruled out after surgery by whole-body Positron Emission Tomography (PET) scan. These patients were subject to adjuvant radiotherapy, while one patient succumbed immediately post-surgery. Primary CNS melanomas are rare with no defined treatment protocols. Histopathology diagnosis is crucial to rule out pigmented mimics.

Intravascular papillary endothelial hyperplasia (IPEH) is a benign, reactive proliferation of endothelial cells within areas of thrombus. It most commonly occurs in the skin and subcutaneous tissue, with less than 40 cases reported in intracranial location. Ours is the first case report from India of IPEH in the cavernous sinus. A 45-year-old male presented with headache and decreased visual acuity. Magnetic resonance imaging (MRI) revealed a well-defined, homogeneously contrast-enhancing mass in the cavernous sinus. Postoperatively, examination of tissue showed organizing thrombus within the vessel wall along with delicate, acellular, pseudopapillary cores. The fibrin-rich connective tissue of these showed blue staining with Masson's trichrome stain. These were lined by a single layer of endothelial cells without evidence of atypia; no nuclear pleomorphism, hyperchromasia, atypical mitosis, or areas of necrosis were seen. Hence, it was diagnosed to be IPEH. Follow-up MRI revealed no residual disease and the patient is disease-free at 8 months. Recognition of this entity by pathologic examination is important to rule out angiosarcoma. Gross total resection is curative. Residual lesions have the potential for recurrence, requiring adjuvant therapy.

Spindle Cell Haemangioma (SCH) is a benign vascular lesion, which commonly affects the dermis and subcutaneous tissue of distal extremities. The occurrence of SCH in the head and neck region and more so in the orbit is very few and rare. SCH should be considered as one of the differential diagnosis in vascular tumors of the orbit. We are reporting a case of solitary SCH in the orbit which was mimicking orbital cavernous venous malformation (orbital venous haemangioma).

Desmoplastic fibroma (DF) is a rare myofibroblastic primary tumor of bone that histologically and biologically mimics the extra-abdominal desmoid tumor of soft tissue. The surgical management of this tumor has been a matter of controversy and its recurrence has been a matter of clinical relevance. In this case report, we describe an unusual case of DF in a 15-year-old male patient who presented with a slow-growing mass in the right posterior mandibular region of 2 years duration. The presence of areas mimicking Giant cell angiofibroma (GCA) is the highlight of the case. The possibility of misdiagnoses is more in early lesions since the available literature shows that immunohistochemistry (IHC) is not of much benefit while differentiating DFs from other spindle cell lesions.

Translocation-associated renal cell carcinoma (t-RCC) is a relatively uncommon subtype of renal cell carcinoma characterized by recurrent gene rearrangements involving the TFE3 or TFEB loci. TFE3 and TFEB are members of the microphthalmia transcription factor (MiT) family, which regulate differentiation in melanocytes and osteoclasts. Renal cell carcinomas (RCCs) associated with Xp11 translocations have gene fusions involving TFE3, which has multiple gene partners; RCCs with t(6:11) translocations have MALAT1-TFEB gene fusions. These tumors are histologically diverse, often have papillary, alveolar, and nested growth pattern with clear and eosinophilic cells and psammoma bodies and are seen commonly in children and young adults, accounting to 40% of pediatric RCCs and 1.6%–4% of adult RCCs. The mean and median patient age is 31 years. Thus, distinguishing t-RCC from its morphologic, immunophenotypic, and molecular mimics has important clinical implications. Directed ancillary testing is an essential aspect to t-RCC cases and may include a panel of immunohistochemical stains, such as PAX8, pancytokeratins, AMACR, CD10, and TFE-3. We, hereby report a case of TFE3 positiveXp11 translocation renal cell carcinoma in a 52-year-old male which is unusual.

IgG4-related disease (IgG4-RD) is an evolving entity characterized by immune mediated multisystem involvement in the form of fibro inflammatory lesions like sclerosing pancreatitis, dacryoadenitis, Reidel thyroiditis, or chronic sclerosing sialadenitis. Barely, the lesions are restricted to kidney (IgG4-RKD: IgG4-related kidney disease) involving either glomerular or extraglomerular compartment. It is challenging to identify and demands an awareness regarding the entity to reduce the number misdiagnosis and missed diagnosis. Here, we report a case of a 45-year-old woman with IgG4 tubulointerstitial nephritis (IgG4-TIN) who presented with unexplained renal dysfunction as her initial manifestation. This is the first case of IgG4-RKD reported from our tertiary care center among 1864 native renal biopsy in the last two years.

Sertoli-Leydig cell tumors (SLCTs) are rare and heterogeneous group of ovarian neoplasms which belong to the sex cord-stromal category of tumors. SLCTs are classified into well, intermediate, and poorly differentiated types. Retiform growth pattern and heterologous elements are commonly found in moderately and poorly differentiated tumors. SLCTs are usually encountered in the third decade of life and patients most often present with virilization. Here, we report two cases of SLCTs of the ovary, both in 2-year-old girls without any hormonal symptoms. The first case was a retiform variant of Sertoli-Leydig cell tumor and the second was a well-differentiated SLCT. Because of its wide spectrum of morphology, several tumors enter in the differential diagnosis and the presence of heterologous elements further complicates the diagnosis. Here, we have described the morphological characteristics of these tumors and discussed their differential diagnoses. SF-1, WT1, and α-inhibin are useful immunostains in establishing the diagnosis and differentiating these from the more the common ovarian germ cell tumors in children.

Carcinoid tumors are defined as rare slow-growing neuroendocrine tumors. A majority of primary ovarian carcinoids occur in association with mature cystic teratoma or are metastatic to the ovary. A 48-year-old post-menopausal woman presented with progressive facial puffiness, and intractable diarrhea. Radiological imaging suggested a 10 × 9 × 9.2 cm right ovarian mass. She underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histopathological examination revealed primary pure carcinoid tumor of the ovary with the synchronous presence of early invasive squamous cell carcinoma of the cervix, along with the icthyosis uteri. The patient is doing well on 5 years of follow-up post-surgery without any recurrence or metastasis. In this report, we intend to highlight the rare association of cervical carcinoma and ichthyosis uteri with this tumor. In addition, we present a short review of the literature, over a decade of ovarian carcinoids associated with carcinoid heart disease.

In the case of single fetal demise in a twin gestation, the fate of the dead twin, surviving twin, and mother depend on the exact time of fetal demise. The dead twin may “vanish” in a first trimester death; form a mummified “fetus papyraceus” due to mechanical compression in the second trimester or show changes of maceration in the third trimester. Hematological complications in the mother and neurological complications in the surviving twin may ensue in later trimester deaths. We report a unique case of an undiagnosed fetus papyraceus incidentally detected in an otherwise normal placenta. Identification of such cases is essential due to the occurrence of severe complications in some of the cases, medicolegal implications for the caregivers, and to improve the understanding of embryological development and fetal demise in twin or multiple gestations.

Composite phaeochromocytomas (CP) are extremely uncommon adrenal medullary tumours where phaeochromocytoma coexists with another adrenal medullary tumour also of neural crest origin. CP includes combination of phaeochromocytoma along with a component of neuroblastoma, ganglioneuroblastoma, ganglioneuroma, benign nerve sheath tumour or a malignant peripheral nerve sheath tumour (MPNST). Here we describe the morphological and immunohistochemical details of a case of CP with MPNST in a 30 years old lady, without history of neurofibromatosis. Only 6 cases of CP with MPNST have been reported so far. We have tabulated a summary of these prior published cases of phaeochromocytoma with MPNST. To our knowledge, this is the first literature review describing the clinico-pathological characteristics of these rare tumours.

Intravascular large B cell lymphoma is a rare type of extranodal lymphoma characterized by selective growth of neoplastic cells in small vessels, especially capillaries, sparing larger arteries, veins and surrounding tissue. The absence of intravascular lymphoma in the traditional sites and difference in mode of presentation with no mass forming lesion as compared to other lymphomas, makes it unique and difficult to diagnose early. It is extremely heterogeneous in its clinical presentation depending on the organ involved. Primary intravascular large B cell lymphoma of the prostate is extremely rare and only 8 cases have been reported in English literature till date, limited to single case reports. This is a rare case of a 76 year old male patient, who came with complaints of urinary obstruction and fever of unknown origin since 15 days. Routine investigations were within normal limits including the complete urine examination, complete blood picture and PSA levels. Mild prostatomegaly was noted on radiology. Patient was catheterized and transurethral resection was done. On histopathological examination, prostatic acini and stroma were normal but the vessels in the stroma which were dilated and thin walled lacking a muscular coat, showed sheets of loosely cohesive cells with moderate eosinophilic to clear cytoplasm, vesicular nuclei, with 1 to 3 prominent nucleoli and mitoses, averaging 4-6/hpf. On immunohistochemistry, the tumor cells were positive for CD 20 and MUM 1 with high MIB1 index of about 90% and were negative for CD3, CD10, Bcl6, PSA, P63, CK7, CK20, HMWCK, and Pancytokeratin. CD31 stained and highlighted the endothelial cells of the vessels. Final diagnosis made after correlating light microscopy and immunohistochemistry was a Primary Intravascular large B-cell lymphoma of the prostate.

Plasmablastic lymphoma (PBL) is a rare aggressive subtype of mature large B cell lymphoma involving almost exclusively the extranodal regions particularly the oral cavity, frequently described in immunocompromised patients. PBL is characterized histologically by diffuse proliferation of large neoplastic cells resembling B immunoblasts or plasmablasts. The diagnosis of PBL can be difficult due to its ambiguous histopathological features mimicking most large cell lymphomas and lacking a distinctive immunophenotypic pattern. They typically lack expression of CD20 and CD79a but may express plasma cell marker, CD138. Aberrant immunoexpression of CD3, a T-cell marker in PBL in the absence of other B-cell markers is exceptionally rare, may potentially lead to incorrect interpretation. Herein, we report a case series of CD3-positive PBL of oral cavity in two individuals, which were initially misdiagnosed as high-grade T-cell lymphomas including extranodal NK/T-cell lymphoma, nasal type. Useful distinguishing clinical settings, histomorphological features, immunohistochemistry and molecular expression profiles of PBL are discussed.

Serum IgG4 is typically measured for Immunoglobulin G4-related Disease (IgG4-RD), a fibroinflammatory condition associated with polyclonal increase in serum IgG4. Yet, increased IgG4 may still be monoclonal, and little is known about IgG4 POEMS syndrome. We present a case of 40-year-old male with a mass lesion in the left sacral ala. The mass was composed of non-neoplastic fibrous tissue and dense infiltrate of mature plasmacytes with dense eosinophilic cytoplasm and eccentrically placed nuclei that express monoclonal Lambda free light chains and show diffuse positivity for IgG and IgG4. We discuss clinical manifestations and challenges encountered in the diagnosis and treatment of this rare coexistence.

Mast cells are naturally distributed in the dermis, respiratory, gastrointestinal/genitourinary mucosa, adjacent to blood vessels, lymphatics, and peripheral nerves. The most common site for the abnormal accumulation of mast cells is the skin, which is known as cutaneous mastocytosis. We report four cases of cutaneous mastocytosis with erythematous maculopapular to bullous lesion along with a positive Darier sign. Skin biopsy, with special stains like Toluidine blue, Giemsa stain, immunohistochemistry (IHC) for CD117, and serum tryptase level correlations were done. Mastocytosis can affect only the cutaneous sites or involve multiple organs. It is most common in infancy with varied clinical presentations, thus requiring a high index of suspicion with histopathological correlation. Although the prognosis is good, there remains a risk of sudden mast cell degranulation due to triggering agents and subsequent collapse.