Primitive neuroectodermal tumor in the skin with features of neuroblastoma in an adult patient

A case of primitive neuroectodermal tumor of an 81-year-old man is presented, which was located in the cutis. The occurrence in this age and this superficial location is unusual and raises wide differential diagnostic possibilities. The tumor demonstrated Homer Wright rosettes, was positive for neuron-specific enolase and ultrastructurally revealed neurosecretory granules. These features support the diagnosis of a peripheral neuroblastoma. We discuss the controversy about the terminology of peripheral neuroblastoma vs. neuroepithelioma, as well as the differential diagnosis of these tumors.     

Measures of tumor proliferative activity.

Tumor proliferative activity, or labeling index, is of interest for gaining insight into the biologic properties of human neoplasm and for providing clinical information that might guide patient management. There has been an abundance of literature reporting experience with standard and newer techniques of measuring tumor proliferative activity. These methods are reviewed with emphasis on technical issues. Particular attention is paid to the development and use of monoclonal antibodies, Ki-67 and anti-PCNA/cyclin. These antibodies are readily available and relatively simple to use. The former has recently been shown to be of prognostic value in non-Hodgkin's large cell lymphomas. A number of studies suggest that indices using these techniques could be useful for a variety of carcinomas, soft tissue tumors, and tumors of the central nervous system.     

PARVOVIRUS B19-ASSOCIATED TRANSIENT RED CELL APLASIA IN CHILDREN: The Role of Bone Marrow Examination in Unusual Presentations

Human parvovirus B19 (PV B19) infection in children commonly presents as fifth disease. Transient red cell crisis, the other manifestation of PV B19 infection, is usually reported in children with chronic hemolytic anemia, with a worsening of the anemia. However, this condition may pass unrecognized in children without an underlying hemolytic disorder, since the anemia may be of a short duration and self-limiting. The authors report 3 cases of PV B19-induced transient aplastic in different clinical settings–-pancytopenia in one child, during induction phase for acute lymphoblastic leukemia in the second, and fever with joint pains in the third. Treatment for PV B19-induced transient aplastic crisis is essentially supportive. There may be a dilemma in patients on immunosuppressive therapy, since initially it is difficult to distinguish between chronic pure red cell aplasia (a condition where intravenous immunoglobulin therapy is beneficial) and transient aplastic crisis, where supportive red cell transfusions suffice. The patient with leukemia also recovered spontaneously despite being on steroids. In all the 3 patients, the pure red cell aplasia recovered spontaneously without administration of intravenous gammaglobulins.     

Five-year colon surveillance after screening colonoscopy

BACKGROUND & AIMS: Outcomes of colon surveillance after colorectal cancer screening with colonoscopy are uncertain. We conducted a prospective study to measure incidence of advanced neoplasia in patients within 5.5 years of screening colonoscopy. METHODS: Three thousand one hundred twenty-one asymptomatic subjects, age 50 to 75 years, had screening colonoscopy between 1994 and 1997 in the Department of Veterans Affairs. One thousand one hundred seventy-one subjects with neoplasia and 501 neoplasia-free controls were assigned to colonoscopic surveillance over 5 years. Cohorts were defined by baseline findings. Relative risks for advanced neoplasia within 5.5 years were calculated. Advanced neoplasia was defined as tubular adenoma greater than > or =10 mm, adenoma with villous histology, adenoma with high-grade dysplasia, or invasive cancer. RESULTS: Eight hundred ninety-five (76.4%) patients with neoplasia and 298 subjects (59.5%) without neoplasia at baseline had colonoscopy within 5.5 years; 2.4% of patients with no neoplasia had interval advanced neoplasia. The relative risk in patients with baseline neoplasia was 1.92 (95% CI: 0.83-4.42) with 1 or 2 tubular adenomas <10 mm, 5.01 (95% CI: 2.10-11.96) with 3 or more tubular adenomas <10 mm, 6.40 (95% CI: 2.74-14.94) with tubular adenoma > or =10 mm, 6.05 (95% CI: 2.48-14.71) for villous adenoma, and 6.87 (95% CI: 2.61-18.07) for adenoma with high-grade dysplasia. CONCLUSIONS: There is a strong association between results of baseline screening colonoscopy and rate of serious incident lesions during 5.5 years of surveillance. Patients with 1 or 2 tubular adenomas less than 10 mm represent a low-risk group compared with other patients with colon neoplasia.