Type D lymphomatoid papulosis simulating aggressive epidermotropic cytotoxic lymphoma.

Three histological subtypes of lymphomatoid papulosis (LyP), type A (histiocytic), type B (mycosis fungoides like) and type C (anaplastic large cell lymphoma like) are well recognized. Two new histological variants, type D (simulating an aggressive epidermotropic cytotoxic lymphoma) and type E (angioinvasive type) has been described recently. We describe a 27‑year‑old man presented with a history of asymptomatic erythematous papules on both upper and lower limbs noted since 10 years of age. There were no systemic symptoms. Biopsy revealed an atypical dermal lymphoid infiltrate with epidermotropism, and the immunohistochemical markers showed a diffuse positivity for CD3, CD8, CD56, T1A and granzyme B with the focal positivity of CD30. All other relevant tests were normal. In this case report of a recently described delineated variant of LyP we emphasize the indolent course of this entity although the histology would suggest a more aggressive disease.

Extracavitary primary effusion lymphoma: A case report from India.

We present a case of extracavitary primary effusion lymphoma presenting, as jejunal polyps in a 38-year-old man. This is the first report of this entity from India. Although rare in our country, the diagnosis should be suspected in cases of CD20 negative large cell lymphoma with plasmablastic or immunoblastic differentiation in seropositive patients. Immunostaining for latency-associated nuclear antigen-1 and in situ hybridization for Epstein-Barr virus-associated RNA will confirm the diagnosis.

V-raf murine sarcoma viral oncogene homolog B (BRAF) mutations in hairy cell leukaemia.

Introduction: Hairy cell leukemia (HCL) is a B-cell non-Hodgkin lymphoma with distinct clinical, morphological and immunophenotypic features; however, there are many other B-cell lymphomas, which closely mimic HCL. Accurate diagnosis of HCL is important as treatment with 2-chloro-2’-deoxyadenosine (cladribine) is associated with >80% chance of complete cure. The recent description of BRAF p.V600E mutations in almost all HCL cases in various studies has not only improved the pathogenetic understanding of this entity but also increased the diagnostic accuracy of this disorder. Aim: The aim of the study was to standardize a molecular test for diagnosis of HCL and compare with standard established morphological, cytochemical and immunophenotypic parameters for HCL diagnosis. Materials and Methods: The incidence of this mutation was sought in 20 patients with either classical HCL or HCL variant (HCLv) by Sanger sequencing and allele-specifi c polymerase chain reaction. BRAF p.V600E mutation was present in all HCL cases and absent in the only HCLv case. Results: A high degree of correlation was noted between the presence of BRAF p.V600E and established diagnostic criteria in 20/20 patients with HCL/ HCLv. Our data supports the observation that this mutation is present in all cases of HCL and is absent in HCLv. Hence, detection of the BRAF p. V600E mutation can be a useful adjunct in the diagnostic algorithm.

Lennert's lymphoma: Clinicopathological profile of five cases.

Background and Aim: Lennert’s lymphoma is a rare variant of peripheral T-cell lymphoma (PTCL) not otherwise specifi ed (NOS) rich in epithelioid histiocytes. This study aims to analyze the clinical, morphologic, and immunophenotypic profi le of cases of Lennert’s lymphoma from our country and determines the utility of T-cell receptor (TCR) gene rearrangement in the diagnosis. Materials and Methods: All cases diagnosed as Lennert’s lymphoma during the period of January 2001 to August 2011 were included in this study. Hematoxylin and eosin (H and E) stained slides and immunohistochemistry results were analyzed and TCR gene rearrangement was performed. Results: There were fi ve cases of Lennert’s lymphoma diagnosed in our institution during this period, which included two males and three females. All cases showed effacement of lymph node architecture by diffuse infi ltration of small lymphoid T cells [CD3+, CD4+, CD8+, T-cell intracellular antigen 1 (TIA-1+), Granzyme B−] and clusters of epithelioid histiocytes throughout the lymph node and scattered large transformed cells (CD20−, CD30+, CD15−/+). TCR rearrangement was done in three cases by polymerase chain reaction (PCR) and showed the presence of a clonal T-cell population. Conclusions: Lennert’s lymphoma constituted 0.11% of all non-Hodgkin lymphomas (NHLs) in our institution. Differentiation from classical Hodgkin’s lymphoma is sometimes diffi cult by morphology and immunohistochemistry alone and TCR gene rearrangement was extremely useful in diagnosis.

Peripheral T-cell lymphoma: Frequency and distribution in a tertiary referral center in South India.

Background and Aim: Peripheral T/NK-cell lymphomas are uncommon types of non-Hodgkin's lymphoma (NHL) with a higher frequency in Far East countries as compared to the West. This study was undertaken to ascertain the frequency and distribution pattern of peripheral T-cell lymphomas (PTCLs) diagnosed in a tertiary care center in South India. Materials and Methods: This retrospective study was carried out in Department of General Pathology, Christian Medical College, Vellore. The time period was for 2 years from 1 st January 2008 till 31st December 2009. All PTCLs were reviewed and classified according to the World Health Organization (WHO) 2008 classification. Results: Of a total of 1032 cases of NHL, 180 cases were PTCL, which accounted for 17.4% cases of all the NHLs. Of these, PTCL, not otherwise specified (PTCL, NOS) was the most common subtype (48 cases, 26.1%), followed by anaplastic large cell lymphoma (41 cases, 22.8%), mycosis fungoides (21 cases, 11.7%), angioimmunoblastic T-cell lymphoma (16 cases, 8.9%), subcutaneous panniculitis like T-cell lymphoma (15 cases, 8.4%), extranodal NK/T-cell lymphoma, nasal type (12 cases, 6.7%), and hepatosplenic T-cell lymphoma (10 cases, 5.6%). The most common primary site of presentation was nodal accounting for 42% followed by cutaneous (34%), upper aerodigestive sites (8.9%), spleen (6.7%), and gastrointestinal tract (GIT; 3.3%). Conclusions: This is the largest single study on PTCLs in India and we document that its frequency is higher than that reported in Western literature and previous Indian studies and almost similar to that reported in some Far East studies. The frequency of mycosis fungoides, subcutaneous panniculitis like T-cell lymphoma, and hepatosplenic T-cell lymphoma was higher than that reported in the World literature and previous Indian studies. The frequency of extranodal NK/T-cell lymphoma and angioimmunoblastic T-cell lymphoma was much lower than that reported in the Far East literature.

Gastrointestinal lymphomas: Pattern of distribution and histological subtypes: 10 years experience in a tertiary centre in South India.

Background and Aim: Gastrointestinal tract (GIT) is one of the major sites of extra-nodal lymphomas constituting 10-15% of all non-Hodgkin's lymphoma cases and about 30-40% of extra-nodal lymphomas. Considerable variation exists in the literature with respect to incidence of the various histological subtypes and sites of involvement. This study was undertaken to ascertain the anatomic distribution, histological subtypes and sites of all GIT lymphomas presenting to a tertiary referral hospital in southern India. Materials and Methods: The histological material of 361 patients over a period of 10 years (2001-2010), with histopathological diagnosis of lymphoma involving the GIT (both primary and secondary), was analyzed retrospectively. All lymphomas were reclassified according to the World Health Organization 2008 classification. Results: These 361 cases include 336 primary and 25 cases of lymphomas, where the involvement was secondary. Primary lymphomas consisted of 267 males (79.64%) and 68 females (20.24%) with a male:female ratio of 3.93:1. The mean age was 45 years (range 3-88). Diffuse large B-cell lymphoma (DLBCL) was the commonest subtype (222 cases; 66.71%), followed by low-grade marginal zone lymphoma of the mucosa associated lymphoid tissue (MALT) type (34 cases; 10.12%) and Burkitt's lymphoma (35 cases; 10.48%). The commonest site was stomach (180 cases; 53.57%), followed by small intestine (79 cases; 23.51%) and large intestine (68 cases; 20.23%), respectively. There were some uncommon types of GIT lymphomas documented during the study. Conclusion: In this largest retrospective single centre study from India, we establish that the pattern of distribution of primary GIT lymphomas (PGLs) in India is similar to the western literature in that the stomach is the commonest site of PGL and DLBCL is the commonest histological subtype. Immunoproliferative small intestinal disease cases were seen in this study, which is uncommon in the west.