CHROMOSOME ANALYSIS OF 9 ENDOCRINE NEOPLASMS OF THE PANCREAS

Endocrine neoplasms of the pancreas differ from the more common adenoc arcinomas of the pancreas not only in histologic appearance, but also in clinical presentation and biologic behavior. Chromosomes were analy zed from nine fresh pancreatic endocrine neoplasms. Clonal chromosomol abnormalities were found in five; all were malignant neoplasms. One s howed only a loss of the Y chromosome and another had a small triploid population of cells in addition to a normal mainline, with a karyotyp e of 1,-2,-3,-4,+5,-6,+7,-11,-14,+17,+18,+20,+mar1,x2,+ mar2,inc. Thre e neoplasms had near-haploid clones. One neoplasm had a composite kary otype of 31-36<n>,X,+1,+3,+5,+7,+9,+10,+17,+18,+mar. Two were from the same patient, who had the autosomal dominant syndrome MEN-1. The same clone, described as 29<n>,X,+add(1)(p12),+5,+7,+8,+18,+19, was found in both the primary pancreatic neoplasm and in the metastatic tumor. T o our knowledge, this is the first report of a haploid clone in both a primary and metastatic solid tumor, and suggests that the near-haploi d state is at least compatible with metastasis. These data, combined w ith the limited reports of cytogenetic data from endocrine pancreatic neoplasms, suggest that at least half of such neoplasms will have an a bnormal karyotype.