The autosomal dominant hereditary cancer syndrome Lynch syndrome (LS; formerly designated hereditary non-polyposis colorectal cancer; HNPCC) arises not only through defects in mismatch repair genes (MLH1, MSH2, MSH6 or PMS2) but also through large 3' deletions of the EPCAM gene. Mutation carriers have 25-70% risk for colorectal cancer, 30-70% risk for endometrial cancer, variable increased risk for ovarian cancer, and increased risks for pancreatic, bladder…
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NCCN clinical practice guidelines recommend prognostic genetic evaluation for newly diagnosed plasma cell myelomas to include karyotyping and FISH for del 13q, del 17p13/ p53, t (4:14)/ FGFR / IGH, t(11;14)/ BCL1/IGH, and t (14;16)/ IGH/ MAF. In this regard, FISH testing is significantly more sensitive than conventional cytogenetics, as is demonstrated by the current case. Prognostically unfavorable abnormalities include del 13q, del 17p13, t (4:14), t(14;16), and hypodiploidy.…
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Synchronous separate primary colon adenocarcinomas, one negative (distal tumor) for codon 12 or 13 KRAS mutation, and one positive (proximal tumor) for codon 12 KRAS mutation.
The vast majority of colorectal cancers express surface EGFR protein, but only a minority responds to anti-EGFR antibody therapy. In patients with metastatic colorectal cancer, the presence of a KRAS gene mutation predicts tumor resistance to anti-EGFR monoclonal antibody therapy. Current…
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Acute panmyelosis with myelofibrosis is rare and typically presents to pathologists with morphologic features resembling a fibrotic stage of primary myelofibrosis or end-stage of myelproliferative neoplasia-NOS, sometimes resembling acute megakaryoblastic leukemia.
However, as in this case, an acute clinical presentation, peripheral smear morphology, and absence of splenomegaly argue against a chronic myelproliferative neoplasm. In this case, diagnosis is further…
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Benign Atypical CD5+ B Cell Proliferation vs Biclonal Chronic Lymphocytic Leukemia / Small Lymphocytic Lymphoma (CLL/ SLL)
An 85 year-old male with clinically suspicious adenopathy underwent bone marrow biopsy.
A decalcified core biopsy demonstrated atypical cellularity averaging approximately 70% comprised predominantly of 75% well differentiated lymphocytes. Scattered myeloid, erythroid and…
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