Mixed Adenoneuroendocrine Carcinoma, Amphicrine Type, of the Small Bowel.

OBJECTIVES: Amphicrine-type mixed adenoneuroendocrine carcinomas are exceedingly rare lesions of the gastrointestinal tract, comprising tumor cells simultaneously demonstrating both neuroendocrine and exocrine features. To date, only 14 cases of amphicrine carcinoma have been reported; here we report the first definitive case of amphicrine carcinoma in the small bowel. METHODS: A 72-year-old woman who sought treatment for nonspecific abdominal complaints was found to have a duodenojejunal junction tumor and underwent radical surgical resection. RESULTS: Morphologically, the tumor consisted of areas of moderately differentiated adenocarcinoma intermingled with areas characteristic of neuroendocrine tumor. The entire tumor showed strong, diffuse immunoreactivity for synaptophysin. Coexpression of exocrine and neuroendocrine features by neoplastic cells indicates bivalent differentiation, and therefore the tumor was classified as an amphicrine carcinoma of the small bowel. CONCLUSIONS: Demonstration of amphicrine carcinoma in the small bowel carries implications with regard to the common origin of exocrine and neuroendocrine cells in the gastrointestinal tract.

A single tube, four-color flow cytometry assay for evaluation of ZAP-70 and CD38 expression in chronic lymphocytic leukemia.

We describe a simple and robust flow cytometry assay for ZAP-70 and CD38 expression. The steps required to validate this assay in a clinical flow cytometry laboratory are described. Two criteria were used to characterize ZAP-70 expression into positive, negative, and indeterminate categories and applied to 111 cases of chronic lymphocytic leukemia (CLL) resulting in 29.7% positive, 56.8% negative, and 13.5% indeterminate cases. A sensitivity-specificity crossover plot between ZAP-70 and CD38 suggested a cutoff of 12.5% for defining CD38 positivity. ZAP-70+ cases were significantly more likely to be at a higher clinical stage and, together with CD38+ cases, were more likely to have unmutated IgV(H). However, for individual patients, the concordance between these markers was not perfect. It may be necessary to evaluate several prognostic markers simultaneously in CLL, and availability of convenient assays for ZAP-70 and CD38 is desirable for optimal clinical decision making.

Distinct expression patterns of CD123 and CD34 on normal bone marrow B-cell precursors ("hematogones") and B lymphoblastic leukemia blasts.

We compared the expression of CD123, the alpha chain of the interleukin-3 receptor, on normal B-cell precursors in bone marrow ("hematogones") from 75 specimens and on leukemic blasts in 45 newly diagnosed B-acute lymphoblastic leukemias (B-ALL) cases. We found that the less mature hematogones (dim CD45+) that express CD34 lack CD123 expression, whereas the more mature hematogones (moderate CD45+) lack CD34 but always express CD123. In contrast with this discordant pattern of CD34 and CD123 expression in hematogones, blasts in 41 (91%) of 45 cases of B-ALL showed concordant expression of the 2 antigens: 80% (36 of 45) cases expressed both antigens, whereas 11% (5 of 45) expressed neither. We found that these distinct patterns of CD34/CD123 expression on hematogones (discordant) and B-ALL blasts (concordant) remain stable after chemotherapy and are useful in differentiating small populations of residual blasts from hematogones that may be simultaneously present.

Bilateral diffuse uveal melanocytic proliferation associated with pancreatic carcinoma: a case report and literature review of this paraneoplastic syndrome.

A case of a 64-year-old man with bilateral diffuse uveal melanocytic proliferation is presented. Bilateral diffuse uveal melanocytic proliferation is a rare paraneoplastic disorder where an underlying malignancy causes bilateral blindness by uveal thickening, serous retinal detachment, and rapid cataract formation. The ocular symptoms and signs herald the onset of this disease, which leads to death in most cases within about 1 year. Including the present case, our literature review reveals that a total of 28 cases of bilateral diffuse uveal melanocytic proliferation have now been reported. Several different malignancies have been associated with bilateral diffuse uveal melanocytic proliferation, but ovarian carcinoma in women and lung and suspected pancreatic carcinoma in men are the most common. Our case is the first to be proven at autopsy to be associated with pancreatic carcinoma. The underlying mechanism remains to be identified, as numerous endogenous factors may regulate the proliferation of uveal melanocytes. Consideration of this entity during clinical examination may lead to an earlier diagnosis of malignancy and an improved prognosis.