Leukemic phase of anaplastic lymphoma kinase positive, anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL) is a distinct type of CD30+ T/null-cell non-Hodgkin's lymphoma that frequently involves nodal and extranodal sites. The presence of leukemic phase in ALCL is extremely rare and occurs exclusively with ALK1-positive ALCL. We describe two patients with ALK1-positive ALCL who developed a leukemic phase with rapid progression of the disease. Immunophenotypic pattern assessed on peripheral blood by flow cytometry revealed CD45, CD30, and CD25 positivity in both cases but NPM-ALK1 was expressed in only one case. Both patients developed leukemic phase as a terminal event of the disease and we share the immunophenotypic features of both cases.

[Evaluation of immunoreactivity of cellular markers of CD15 and CD30 among patients with classic Hodgkin's lymphoma]

Hodgkin's lymphoma [HL] is a curable lymphoid malignancy. Different Immunohistochemical markers specially CD15 and CD30 are used to diagnose HL and differentiate it from other lymphomas including anaplastic large cell lymphoma [ALCL]; this study was carried out in patients with Hodgkin's lymphoma to determine the frequency of these markers in Iranian patients with HL. A cross sectional study was done out on all patients with definite diagnosis of classic Hodgkin's lymphoma in the selected hospitals. Patients were classified according to WHO classification of the HL type into: mixed cellularity, nodular sclerosis, lymphocyte rich and lymphocyte depletion subtypes. CD15 and CD30 immunophenotype were detected by monoclonal immunostaining method. The frequency was determined in each group and C.I. [confidence interval] was calculated for the Iranian population. The studies were done on 65 patients. Mean age was 31.9 +/- 18.1 years. 37 [56.9%] were male. CD15 and CD30 was positive in 50 [76.9%] and 58 [89.2%] respectively. Both markers were positive in 46 [70.8%] and were negative in 3 [4.6%]. There was no significant relationship between CD15 and CD30 positivity and age/ gender [p<0.6]. It seems that there is a high frequency of positivity for CD15 or CD30 in Iranian patients with Hodgkin's lymphoma. These markers are useful in diagnosis of Hodgkin's lymphoma. However, in cases who are CD15 negative and CD30 positive, it is better to use additional markers for avoiding misdiagnosis as anaplastic large cell lymphoma

CD20 positivity in classical Hodgkin's lymphoma: Diagnostic challenge or targeting opportunity.

BACKGROUND: It is now well established that Hodgkin cells are clonal B cells with a CD30 and CD15 phenotype. However, on immunohistochemistry, in our experience and the experience of others, CD20 positivity in an otherwise typical classical Hodgkin's Lymphoma is not uncommon and if associated with CD15 negativity poses a potential diagnostic trap and is likely to be called B-NHL. OBJECTIVE: To assess the frequency of B-cell related antigens CD20 and CD79a in classical Hodgkin's Lymphoma. MATERIALS AND METHODS: A total of 91 consecutive cases of classical Hodgkin's Lymphoma were analyzed for co-expression of CD20 and CD79a. Both males and females of all ages were included in this study. All cases of nodular lymphocyte predominant Hodgkin's Lymphoma were excluded. All the cases were stained with a panel of antibodies including LCA, CD20, CD79a, CD30, CD15, CD3, EMA and Alk. Protein. RESULTS: All 91 cases of classical Hodgkin's Lymphoma showed negativity for LCA and positivity for CD30. Eighteen cases (19.8%) showed distinct membrane staining with CD20 in most of the large atypical cells. However, out of these, only 7 cases (7.7%) showed CD79a co-expression, which was largely focal. CD15 negativity with CD20 positivity was seen in 7 (7.7%) cases of otherwise typical classical Hodgkin's Lymphoma. CONCLUSIONS/RECOMMENDATIONS: CD20 expression is frequent in classical Hodgkin's Lymphoma and our results are in consensus with reported literature on this subject. In these cases, LCA negativity of large cells was extremely useful in clinching the right diagnosis.

A case of rhabdomyosarcoma masquerading as acute leukemia at presentation: a case report.

Non-hematopoietic malignancies infiltrating bone marrow have always been a source of erroneous diagnosis. Among these, the small round cell tumors like neuroblastomas and rhabdomyosarcomas mimick the hematopoietic blasts. Several case reports of rhabdomyosarcoma mimicking acute leukemia, clinically and morphologically at presentation have been reported in the literature. To the best of our knowledge such an entity has not been reported in Indian literature. We report here one such case of alveolar rhabdomyosarcoma masquerading as acute leukemia. A thorough clinical examination with high degree of suspicion on bone marrow morphology and judicious use of appropriate immunohistochemistry markers will solve many of these cases.

Primary Systemic Anaplastic Large Cell Lymphoma in a Single Korean Institution: Clinical Characteristics and Treatment Outcome

Despite advances in the characterization of anaplastic large cell lymphoma (ALCL), little data is available on Asian patients. We report here upon single Korean institution's experience regarding the clinical characteristics and outcomes of ALCL. We performed a retrospective study of 32 adults with ALCL. Most of the patients received anthracycline-based chemotherapy. Ann Arbor stage III-IV, B symptoms, high-intermediate/ high International Prognostic Index (IPI), and extranodal disease at diagnosis were present in 56%, 44%, 41%, and 63%, respectively. Compared with Western studies, the male/female ratio (4.3) was markedly higher and skin (9%) and bone involvement (9%) were less frequent. The staining results for anaplastic lymphoma kinase were positive in 6 (33%) of 18 cases available. The complete response (CR) rate was 62% (95% CI, 44-80%). With a median follow-up of 51.0 months, 5 yr overall survival was 40+/-11%. The 3 yr relapse-free survival for the 18 patients who achieved CR was 74+/-12%. Age, performance status, lactate dehydrogenase, extranodal disease sites number, and IPI were correlated with treatment response and survival. Our data suggest that Korean ALCL patients appear to have a higher male/female ratio, less frequent skin/bone involvement, and lower CR rate compared with those of Western studies.

Utility of CD15, CD30 & CD45 in the immunohistochemical diagnosis of Hodgkin's disease by antigen retrieval method.

The utility of staining Reed-Sternberg (RS) cells with CD30, CD15 and CD45 as a diagnostic aid in Hodgkin's disease (HD) and the value of microwave citrate antigen retrieval (AR) method in improving the results of immunohistochemical (IHC) studies were evaluated. Histological and immunohistological studies were carried out on 21 patients with HD seen from January 1987 to December 1996 in the Pathology Department of the Cumhuriyet University, School of Medicine. Avidin biotin peroxidase complex (ABC) was used in IHC study as a method for detection of RS cells. Monoclonal antibodies CD30, CD15 and CD45 were applied on formalin fixed paraffin embedded tissue sections. In order to enhance the immunoreactivity, microwave citrate AR method and proteolytic pretreatment were used. The reactivity of RS cells and staining patterns were determined. In 14 (70%) of the 20 patients, RS cells stained positively with CD30, in 16 (80%) CD15 staining was positive and only 1 (5%) was positively stained with CD45. A combination of cytoplasmic with cell surface staining was common with CD30, while paranuclear deposit with cell surface and cytoplasmic staining was common with CD15. In conclusion, to facilitate the detection of RS cells in formalin fixed paraffin embedded tissues, the application of a panel of markers appears to be necessary. Also AR method seems to be helpful in obtaining optimal results on formalin fixed paraffin embedded tissue.