PAPILLARY IMMATURE METAPLASIA (IMMATURE CONDYLOMA) OF THE CERVIX - A CLINICOPATHOLOGICAL ANALYSIS AND COMPARISON WITH PAPILLARY SQUAMOUS CARCINOMA

Papillary immature metaplasia (PIM) is a variant of human papillomavir us (HPV) 6 or 11 infection. PIM resembles an immature metaplasia but h as filiform papillae, variable cytological atypia, and, frequently, ex tension into the endocervical canal. Because the unusual morphology an d presentation of PIM may cause confusion between this and other benig n and malignant papillary neoplasms, we conducted a clinicopathologic analysis of PIM and compared expression of Ki-67 between PIM, condylom a, and papillary carcinoma. Data on patient age, duration of the lesio ns, and procedures, including cone biopsy, were obtained. The distribu tion and intensity of staining for Ki-67 in the epithelium was recorde d and compared with both condyloma and papillary carcinoma. HPV typing was performed by polymerase chain reaction (PCR) and restriction frag ment length pleomorphism analysis (RFLP). Ten of 13 PIMs were HPV 6/11 positive. Three cases contained areas closely resembling condyloma El even cone biopsies were performed on nine cases. Three were found to h ave a coexisting high-grade squamous intraepithelial lesion that was e ither HPV 6/11 negative or contained another HPV type. AU PIMs display ed variable staining for Ki-67 with a low index of staining in the mid and upper epithelial layers. In contrast, areas of condyloma had sign ificantly strong er staining in areas with viral cytopathic effect (ko ilocytosis). Six papillary carcinomas were analyzed and displayed mode rate to diffuse staining, including staining of the superficial cell n uclei. PIM is a distinct pathological subset of cervical condyloma tha t frequently is managed by cone biopsy and may persist The marked redu ction in Ki-67 staining in superficial cell layers distinguishes PIM, from some condylomata and most HSILs and papillary carcinomas. Immunos taining thus may be helpful in distinguishing Phl from papillary carci noma, although the differentiation of the two is best made on morpholo gical grounds. HUM PATHOL 29:641-648. Copyright (C) 1998 by W.B. Saund ers Company.