Allelic losses at 3p and 11p are detected in both epithelial and stromal components of cervical small-cell neuroendocrine carcinoma

Microdissected epithelial and stromal. cells from 15 cervical small-cell ca rcinoma patients and 9 healthy control subjects were assessed for loss of h eterozygosity with polymorphic DNA markers at chromosomes 3p and I lp. Amon g malignant lesions assessed with 7 markers at 3p, 21 allelic losses were d etected from 193 informative samples. Of losses, 20 were in epithelial and 1 was in normal-appearing stromal cells. Among losses in epithelial cells, 16 were from 44 samples informative for 3 markers within 3p21.2-p14.2 (0.36 loss/sample), whereas only 4 were from 54 samples informative for 4 marker s outside the region (0.09 loss/sample), suggesting a "hot spot" of genetic alterations within 3p21.2-p14.2. Among malignant lesions assessed with 2 m arkers within 11p14-p12, 15 losses were seen in 52 informative samples. Of losses, 10 were in epithelial and 5 were in normal-appearing stromal cells. Of 10 epithelial samples showing losses within 11p14-p12, 8 also displayed losses within 3p21.2-p14.2, suggesting a concurrent involvement of these l oci in tumor development or progression. The five losses in stromal cells w ere in four cases that showed no loss in epithelial cells with same markers , suggesting that stromal cells might play initiative roles in tumor develo pment.