Distribution of human papillomavirus types in cervical cancers in Hong Kong: current situation and changes over the last decades.

Human papillomavirus (HPV) type distribution among cervical cancers and its possible changes over time are key issues that determine the cost-effectiveness of HPV vaccines. Cervical cancers diagnosed during 3 periods (1997-2007, N = 280; 1984-1986, N = 74; 1972-1973, N = 81) in Hong Kong were examined for HPV type distribution using sensitive broad-catching methods. The results showed a variation in HPV distribution between histological groups. Among cervical squamous cell carcinoma (SCC) cases diagnosed over the past 10 years, HPV16 was most commonly found (61.2%), followed by HPV18 (17.7%), HPV52 (14.7%) and HPV58 (9.9%), whereas adeno/adenosquamous cell carcinoma was dominated by HPV18 (56.3%) and HPV16 (50.0%). The proportion of HPV16-positive SCC showed a significant linear trend of increase with time (45.2% for 1972-1973, 58.8% for 1984-1986, 61.2% for 1997-2007; p(Trend) = 0.023), whereas HPV52-positive SCC decreased with time (30.1% for 1972-1973; 29.4% for 1984-1986, 14.7% for 1997-2007; p(Trend) = 0.001). Vaccines comprising HPV16/18 cover 62.6% of SCC and 93.8% of adeno/adenosquamous carcinoma in Hong Kong, and inclusion of HPV52 and HPV58 can increase the coverage by 18.4% for SCC and 4.1% for adeno/adenosquamous cell carcinoma. HPV type distribution may change over time. Further investigations to reveal the determinants for such changes and continuous monitoring for possible type replacement as a result of widespread long-term use of HPV vaccines are warranted. Multiple infections are commonly revealed by sensitive broad-catching methods such as those used in this study. However, their implication on vaccine efficacy and cost-effective analyses should be taken cautiously.

Atypical epithelial proliferations in acquired renal cystic disease harbor cytogenetic aberrations.

Acquired renal cystic disease (ARCD) complicating end-stage renal failure confers an increased risk for renal cell carcinoma, and atypical epithelial proliferation in the cysts may represent the precursor lesion. In this report we used an interphase cytogenetic technique to analyze the karyotypic features of various forms of atypical epithelial proliferations in a patient with ARCD. Both kidneys harbored numerous simple and atypical cysts. In addition, papillary tufts and a hitherto undescribed cribriform epithelial proliferation were found in the right kidney. The left kidney contained a 10-mm renal cell carcinoma with features indeterminate between clear cell and papillary types. There was gain of chromosome 7 in the papillary tufts; gain of chromosomes 7 and 17 in the cribriform lesion; gain of chromosomes 7, 12, 17, 20, and Y in the atypical cysts; and gain of chromosomes 7, 12, 17, and 20 in the renal cell carcinoma. These chromosomal aberrations suggest that atypical epithelial proliferations in ARCD represent early neoplastic lesions.

The contribution of bifunctional SkipDewax pretreatment solution, rabbit monoclonal antibodies, and polymer detection systems in immunohistochemistry.

CONTEXT: In immunohistochemistry, nonstandardized antigen retrieval protocols and fluids, poor-quality antibodies, and the presence of endogenous biotin frequently lead to incorrect results. Recently, advanced reagents including bifunctional SkipDewax pretreatment solution (BSPS), rabbit monoclonal (RM) antibodies, and biotin-free polymer detection systems (PDSs) have been developed, which, it is claimed, resolve these problems. OBJECTIVES: To determine whether BSPS, RM antibodies, and biotin-free PDSs improve the accuracy of immunohistochemistry; to optimize a new protocol consisting of a combination of BSPS, RM antibodies, and PDSs; and to compare it with a conventional protocol. DESIGN: The efficacies of BSPS, RM antibodies, and PDSs were compared with those of their respective conventional reagents using multitissue spring-roll sections. The new protocol was compared with a conventional protocol using Ki-67 immunostaining of 49 colorectal carcinoma specimens. RESULTS: For antigen retrieval, BSPS resulted in similar or better tissue staining than an EDTA solution, but the efficacy of BSPS decreased when it was reused. Most RM antibodies resulted in a greater proportion of positive cells than the corresponding non-RM antibodies, which did not produce satisfactory results in the absence of antigen retrieval. The PDSs Bond, ChemMate, and SuperPicture resulted in a high percentage of positive cells, good staining intensities, and low backgrounds. Other PDSs, except that from Ventana, resulted in high backgrounds and false positivity. The new combined protocol resulted in better Ki-67 staining than the conventional assay. CONCLUSIONS: Bifunctional SkipDewax pretreatment solution, RM antibodies, and PDSs improve staining quality and diagnostic accuracy of immunohistochemistry assays and provide a foundation for standardization.