Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 2932
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size

Ahead of print publication
Detection of focal lesions in the clot section with negative bone marrow aspirate and trephine biopsy—A series of 5 cases

1 Department of Pathology, Christian Medical College and Hospital, Ludhiana, Punjab, India
2 Department of Pathology, MMMCH, Kumarhatti (Solan), Himachal Pradesh, India

Click here for correspondence address and email

Date of Submission18-Mar-2022
Date of Decision06-Jul-2022
Date of Acceptance08-Jul-2202
Date of Web Publication16-Nov-2022


Bone marrow aspiration and trephine biopsies are commonly used procedures in clinical practice. The practice of making a clot section by using the leftover blood from the bone marrow aspirate material is not a commonly followed practice across centers. A clot section has the advantage of studying the added material with an increased possibility of detecting focal lesions such as myeloma, lymphoma, granuloma, and metastasis in the bone marrow. Bone marrow aspirate, trephine biopsy, and clot section were compared for the detection of focal lesions in a series of 5 patients, 3 of who presented with a history of fever and 2 were already diagnosed cases of Hodgkin lymphoma. Focal lesions were detected in the 5 cases in the clot section alone, whereas bone marrow aspirate and trephine biopsy did not show any focal lesion. Granulomatous infiltration was detected in 3 patients, and lymphomatous infiltration was detected in 2 patients in the clot section, whereas bone marrow aspirate and trephine biopsy were negative for any focal lesion in all 5 cases. A clot section is particularly useful in the detection of bone marrow lesions with a focal distribution. Hence, it must be studied alongside bone marrow aspirate smears, touch smears, and trephine biopsy to increase the diagnostic yield.

Keywords: Bone marrow clot section, bone marrow trephine biopsy, focal lesion

How to cite this URL:
Bhatti V, Kakkar N. Detection of focal lesions in the clot section with negative bone marrow aspirate and trephine biopsy—A series of 5 cases. Indian J Pathol Microbiol [Epub ahead of print] [cited 2022 Dec 7]. Available from:

   Introduction Top

Bone marrow aspiration and biopsy is an important procedure for diagnosing various hematological and some non-hematological disorders. Apart from morphological examination, the material obtained can be used for immunophenotyping, cytogenetic, molecular, and other specialized investigations.[1] Focal lesions are picked up more frequently on trephine biopsy than on aspirates.[2]

In cases where trephine biopsy is not adequate or it is not done, a clot section can be made by collecting the leftover marrow fragments after preparing aspirate smears. This can then be processed and studied similar to routine histopathology biopsies.[3],[4] The study of clot sections brings in an added benefit in the diagnosis of diseases such as tuberculosis, myeloma, lymphoma, and metastatic deposits that often have a focal distribution and may not be detected if limited bone marrow examination is done.[1],[4],[5],[6],[7]

We present 5 patients who had granulomas or lymphomatous infiltration in the clot section with negative aspirate smears and trephine biopsy.

   Case Summary Top

Patient 1

A 55-year-old gentleman presented with fever and cough for 3 months along with bicytopenia. Systemic examination revealed crepitations in the right infrascapular region and hepatosplenomegaly. Computerized tomography (CT) scan of the chest showed multiple large fibrocavitatory lesions involving apical segments of bilateral upper lobes and the superior segment of the right lower lobe with evidence of varicose bronchiectasis, suggestive of reactivation of pulmonary tuberculosis. In view of CT chest findings and granulomas in bone marrow, a diagnosis of tuberculosis was considered. He also had liver cirrhosis with esophageal varices and was found to be immunoreactive for hepatitis C. He was started on anti-tubercular treatment (ATT); however, he was lost to follow-up.

Patient 2

A 66-year-old gentleman, an old treated case of tuberculosis 3 years ago, presented with fever and swelling in the neck for 1 month. Examination showed left supraclavicular lymphadenopathy and mild hepatosplenomegaly. Lymph node biopsy was done, which on histopathology and immunohistochemistry showed T-cell-rich large B-cell lymphoma with occasional epithelioid cell granulomas.

Patient 3

A 14-year-old boy, a known case of beta-thalassemia major, post-bone-marrow -transplant 1 year back presented with fever off and on with evening rise of temperature for 10 months. Systemic examination showed hepatosplenomegaly. CT scan of the chest was normal. Tuberculosis polymerase chain reaction sent from bone marrow aspirate was positive. The patient was started on ATT, to which he responded and improved clinically.

Patient 4

A 70-year-old lady presented with left axillary swellings for 1 year. Fine-needle aspiration cytology from the axillary mass was suggestive of Hodgkin's lymphoma.

Patient 5

A 62-year-old lady, a diagnosed case of classic Hodgkin lymphoma post-chemotherapy, 8 years back, presented with high-grade fever for 2 weeks.

Ziehl Neelsen staining performed on bone marrow in all patients with granulomatous pathology was negative.

Hematological investigations in 5 patients are shown in [Table 1].
Table 1: Hematological investigations

Click here to view

Bone marrow aspirate, trephine, and clot section findings of all 5 cases [Figure 1]a, [Figure 1]b, [Figure 1]c, [Figure 1]d, [Figure 1]e are given in [Table 2].
Figure 1: (a–d) Bone marrow clot sections showing granulomata comprising of epitheloid cells. (a) Langhans giant cells. (e) Mononuclear Reed Sternberg cells in the clot section, suggestive of lymphomatous infiltration

Click here to view
Table 2: Clinical profile and bone marrow aspiration, trephine biopsy, and clot section findings

Click here to view

   Discussion Top

Bone marrow aspiration and biopsy is an important procedure for diagnosing various hematological and non-hematological disorders. The indications include investigation of unexplained anemia, thrombocytopenia, pancytopenia, suspected acute leukemia, lymphoma, multiple myeloma, granulomas, metastasis, etc.[1] Among indications of bone marrow examination, the identification of granuloma, lymphoma, myeloma, and metastatic disease pose a diagnostic challenge due to the focal distribution of these conditions.

Bone marrow examination includes studying aspirate smears, trephine biopsy, touch imprints, and clot section.. Out of these, trephine biopsy is considered most helpful in detecting focal lesions.[8],[9] Sometimes bilateral trephine biopsies are performed to increase the yield of detecting focal lesions.[10]

In most of the centers, the practice of making a clot section is not followed. The preparation of the clot section is done by leaving the aspirated bone marrow blood to clot in a watch glass. The clot is then transferred to a container with a fixative (formalin), and routine histopathological processing is done.[3]

The clot section increases the chances of detecting focal lesions as it represents the study of additional aspirated bone marrow material.[3] Mathur et al.[4] in their study described the detection of multiple myeloma on clot sections. Bone marrow clot sections can be used for performing immunohistochemistry with CD138 for multiple myeloma cases.[6] Multiple myeloma detection on clot sections alone, not seen in trephine and aspiration, was described in another case report.[5]

In our case series comprising 5 cases, granulomatous pathology was detected only on clot sections in 3 patients, whereas lymphomatous infiltration was detected in 2 patients on clot sections alone.

In 2 out of 3 patients with granulomatous pathology, ATT was started, whereas one patient was lost to follow-up.

The clot section has other advantages such as aspirated material, which is otherwise not utilized, is used to make clot sections; hence, the otherwise leftover material is utilized. The processing of clot sections does not require decalcification and is available for examination before trephine biopsy and results of immunohistochemistry performed on clot sections are better due to the lack of decalcification-associated nucleic acid or protein damage.

   Conclusion Top

A clot section is a useful adjunct to the study of bone marrow aspirate and trephine biopsy. It may be particularly useful in the detection of bone marrow lesions with a focal distribution. Clot sections must be studied alongside bone marrow aspirate smears, touch smears, and trephine biopsy to increase the diagnostic yield.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

   References Top

Bains BJ. Bone marrow aspiration. J Clin Pathol 2001;54:657-63.  Back to cited text no. 1
Patel S, Nathani P, Nathani S, Shah CK. Diagnostic role of bonemarrow aspiration and trephine biopsy in haematological practice. Guj Med J 2015;70:37-41.  Back to cited text no. 2
Lee SH, Erber WN, Porwit A, Tomonga M, Peterson LC. ICSH guidelines for standardization of bone marrow specimens and reports. Int J Lab Hematol 2008;30:349-64.  Back to cited text no. 3
Mathur K, Soutar R. The additional role of bone marrow particle sections (“clot section”) in confirming marrow involvement by multiple myeloma: A single centre study. Int J Lab Hematol 2010;32:179-80.  Back to cited text no. 4
Kakkar N, Das S. Relapse of multiple myeloma: Diagnosis by clot section alone with negative bone marrow aspirate and trephine biopsy. Indian J Pathol Microbiol 2009;52:290-1.  Back to cited text no. 5
[PUBMED]  [Full text]  
Matsue K, Matsue Y, Kumata K, Usui Y, Suehara Y, Fukumoto K, et al. Quantification of bone marrow plasma cell infiltration in multiple myeloma: Usefulness of bone marrow aspirate clot with CD 138 immunohistochemistry. Hematol Oncol 2017;35:323-8.  Back to cited text no. 6
Cantadori LO, Gaiolla RD, Niero-Melo L, Oliveira CO. Bone marrow aspirate clot: A useful technique in diagnosis and follow-up of hematological disorders. Case Rep Hematol 2019;2019:7590948.  Back to cited text no. 7
Jeevan SK, Paul-Tara R, Uppin S, Uppin M. Bone marrow granulomas: A retrospective study of 47 cases (A single centre experience). Am J Int Med 2014;2:90-4.  Back to cited text no. 8
Bains BJ. Bone marrow trephine biopsy. J Clin Pathol 2001;54:737-42.  Back to cited text no. 9
Nanda A, Basu S, Marwaha N. Bone marrow trephine biopsy as an adjunct to bone marrow aspiration. J Assoc Physicians India 2002;50:893-5.  Back to cited text no. 10

Correspondence Address:
Vandana Bhatti,
Department of Pathology, Christian Medical College and Hospital, Brown Road, Ludhiana - 141 008, Punjab
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ijpm.ijpm_253_22


  [Figure 1]

  [Table 1], [Table 2]


 Article in PDF
     Search Pubmed for
    -  Bhatti V
    -  Kakkar N

   Case Summary
    Article Figures
    Article Tables

 Article Access Statistics
    PDF Downloaded6    

Recommend this journal