[Vulvar intraepithelial neoplasia: a clinicopathologic study of twenty cases].

OBJECTIVE: To investigate the clinical, pathological and immunohistochemical features of vulvar intraepithelial neoplasia (VIN). METHODS: According to the 2004 modified terminology of International Society for the Study of Vulvovaginal Diseases (ISSVD), the cases were diagnosed as VIN from patients who had performed vulvar biopsy in Beijing Wuzhou Women's Hospital from February 2009 to December 2011, which were reclassified as usual VIN and differentiated VIN. The clinical and pathological studies were conducted respectively. MaxVision immunohistochemical staining was used to detect the expression of Ki-67, p16 and p53 proteins. RESULTS: There were 20 cases of VIN in 237 patients, and the incidence of VIN was 8.4% in all of contemporary vulvar biopsy. In 17 cases of usual VIN, mean age was 29.6 years, the lesion typically presented with atypical cells involving almost all layers of the epithelium, which was equivalent to the high-grade squamous intraepithelial neoplasia of cervix. Immunohistochemistry for Ki-67 and p16 was strongly positive in usual VIN. High risk human papillomavirus (HPV) detection was also positive. The incidence of differentiated VIN was less than usual VIN, and there were only 3 cases in this study. In differentiated VIN, patients aged over 50 years, with mean of 53.7 years, and the lesion most commonly presented with lichen sclerosis background. There were epithelial thickening and extending, and parakeratosis, and atypia was strictly confined to the basal and parabasal layers of the epithelium where the cells enlarged with abundant eosinophilic cytoplasm, presented with prominent nucleoli, increased cellularity and abnormal keratinization. In differentiated VIN, p53 was strongly positive, Ki-67 and p16 immunohistochemical expression was confined to the basal layer only. CONCLUSIONS: VIN is a precursor of invasive squamous cell carcinoma of the vulva. The modified terminology of ISSVD classifies VIN as high-grade lesions. Definitive pathological diagnosis of VIN plays an important role in its timely treatment and the prevention of vulvar carcinoma.

[Detection of EWS-WT1 fusion transcripts in paraffin-embedded tissues for desmoplastic small round cell tumor].

OBJECTIVE: To detect the EWS-WT1 chimeric mRNA in desmoplastic small round cell tumor (DSRCT) and its clinicopathological significance. METHODS: Formalin fixed, paraffin-embedded tumor specimens from 4 examples of this entity were studied by reverse transcriptase polymerase chain reaction to detect the EWS-WT1 fusion transcripts resulting from the chromosomal translocation t(11;22)(p13;q12). The following tumor specimens were included as controls: 2 Ewing's sarcomas/primitive neuroectodermal tumors (PNET/ES), 2 alveolar rhabdomyosarcomas, and 2 lymphomas. RESULTS: EWS-WT1 fusion transcripts were detected in 3 of 4 desmoplastic small round cell tumors but not in any other tumor types studied as controls. CONCLUSION: The analysis of the EWS-WT1 fusion transcript which was performed on formalin-fixed, paraffin-embedded tissues is a sensitive and specific method in the diagnosis and differential diagnosis of DSRCT.

[Value of special stains and immunohistochemistry in the diagnosis of renal epithelial neoplasms].

OBJECTIVE: To study the diagnosis and differential diagnosis of renal epithelial neoplasms. METHODS: Ninety-one cases of renal epithelial neoplasms with detailed pathologic records were enrolled. In addition to microscopic examination, Mowy's colloidal iron staining and immunohistochemical studies (CD10, vimentin and CK7) were also performed. RESULTS: Among the 91 cases, there were 78 (86%) clear cell renal carcinoma cases, 8 (9%) papillary renal carcinoma cases, 4 (4%) chromophobe renal carcinoma cases and 1 (1%) renal oncocytoma case. Sixty-three of the 78 clear cell renal carcinoma cases were positive for CD10 and 69 were positive for vimentin (81% and 88% respectively), with prominent cell membrane staining. The majority (74/78) of clear cell renal carcinoma were negative for CK7. All 17 clear cell renal carcinoma cases showed negative or focal coarse droplet-like staining pattern for Mowy's colloidal iron stain. All 4 chromophobe renal cell carcinoma cases showed prominent cell membrane staining for CK7 and blue reticular staining pattern for Mowy's colloidal iron stain. All of which were negative for CD10 and vimentin. The case of renal oncocytoma failed to react with antibodies to CD10, vimentin and CK7, or Mowy's colloidal iron stain. CONCLUSIONS: CD10, vimentin, CK7 and Mowy's colloidal iron stains have proved to be useful in differential diagnosis of common renal tumors which may not be easily distinguished on the basis of histologic examination alone.