Hepatosplenic T-cell lymphoma presented with massive splenomegaly and pancytopenia - a case report.

BACKGROUND: Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of peripheral T-cell lymphoma. Patients usually present with splenomegaly and pancytopenia but without lymphadenopathy. Immunohistochemistry (IHC) staining of bone marrow biopsy shows intra-sinusoidal infiltration of CD3 and CD56 T-lymphocytes. Current treatment strategy of HSTCL includes a CHOP regimen (cyclophosphamide, adriamycine, vincristine, prednisone) followed by autologous transplantation. CASE: A 28-year-old male presented with abdominal fullness, weight loss, and massive splenomegaly. Laboratory findings revealed pancytopenia. A CT scan of the abdomen displayed hepatomegaly and massive splenomegaly. The bone marrow pathology examination showed monotonous medium-sized lymphocytes with some cluster of atypical lymphocytes with loosely condensed chromatin and pale cytoplasm. The intra-sinusoidal location was more prominent after using IHC staining of CD3 and CD56, which are characteristics of HSTCL. We administered CHOP-based regiment every 3 weeks for 3 cycles; however, the response was a stable disease. Since the splenomegaly was still massive and compromised the patient, the multidisciplinary team decided to perform splenectomy. Unfortunately, the patient did not survive the surgery. CONCLUSION: Hepatosplenic T-cell lymphoma is a rare aggressive disease, which is part of peripheral T-cell lymphoma. CHOP-based chemotherapy appeared to be ineffective, and we need further studies to find the optimal treatment of HSTCL.

Primary breast lymphoma - a case report.

BACKGROUND: Primary breast lymphoma is a rare disease and accounts for 0.4-0.5% of malignant breast neoplasms and 1.7-2.2% of extra-nodal lymphomas, with diffuse large B-cell lymphoma (DLBCL) as the most common histologic subtype. CASE: A 47-year-old female with beta thalassemia presented with a lump of the left breast, redness, pain, and swelling of her left breast. Physical examination showed tender, red, swollen left breast. Laboratory findings show mild anemia and normal level of lactate dehydrogenase 329 U/L (normal range: 240-480 U/L). PET scan showed hypermetabolic mass with irregular margins covering the whole left breast quadrants with the size of 11.25 x 5.17cm with left pectoralis major, left parasternal, and left axillary hypermetabolic nodules. Histopathology and immunohistochemistry staining showed a non-germinal center B-cell-like subtype of DLBCL CD20+. We administered the R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednison) every 3 weeks for 6 cycles. The response was complete remission. The patient tolerated the chemotherapy well and achieved long term complete remission. CONCLUSION: Primary breast lymphoma is a rare disease with the most common subtype is diffuse large B-cell lymphoma. Systemic chemother-apy R-CHOP is the treatment option for primary breast diffuse large B-cell lymphoma.

RUNX3 is oncogenic in natural killer/T-cell lymphoma and is transcriptionally regulated by MYC.

RUNX3, runt-domain transcription factor, is a master regulator of gene expression in major developmental pathways. It acts as a tumor suppressor in many cancers but is oncogenic in certain tumors. We observed upregulation of RUNX3 mRNA and protein expression in nasal-type extranodal natural killer (NK)/T-cell lymphoma (NKTL) patient samples and NKTL cell lines compared to normal NK cells. RUNX3 silenced NKTL cells showed increased apoptosis and reduced cell proliferation. Potential binding sites for MYC were identified in the RUNX3 enhancer region. Chromatin immunoprecipitation-quantitative PCR revealed binding activity between MYC and RUNX3. Co-transfection of the MYC expression vector with RUNX3 enhancer reporter plasmid resulted in activation of RUNX3 enhancer indicating that MYC positively regulates RUNX3 transcription in NKTL cell lines. Treatment with a small-molecule MYC inhibitor (JQ1) caused significant downregulation of MYC and RUNX3, leading to apoptosis in NKTL cells. The growth inhibition resulting from depletion of MYC by JQ1 was rescued by ectopic MYC expression. In summary, our study identified RUNX3 overexpression in NKTL with functional oncogenic properties. We further delineate that MYC may be an important upstream driver of RUNX3 upregulation and since MYC is upregulated in NKTL, further study on the employment of MYC inhibition as a therapeutic strategy is warranted.