Human papillomavirus (HPV) prevalence and types among women attending regular gynecological visit in Tehran, Iran.

BACKGROUND: Persistent infection by HPV is now recognized as the main cause of cervical cancer. HPV prevalence data is not yet available in Iran. This study is organized to evaluate type-specific HPV prevalence and to compare it with Pap smear results among Iranian women attending regular gynecological visits. METHODS: A total of 851 women aged 18 - 65 years, attending regular gynecological visits, were retrospectively evaluated. HPV detection and genotyping was performed by use of Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP). Cytological evaluation was done by Papanicolaou method and the association between cytological results and HPV status was analyzed. RESULTS: 19 different HPV types were detected in 265 of the 851 specimens (31.1%). Overall HPV infection as well as infection with High Risk (HR) HPV types was highest in women aged 18 - 25 years and decreased with age. Type-specific prevalence of HPV-16 and 18 was 7.3% and 2.8%, respectively, and a large number of women (20.2%) were infected by HR HPV types other than HPV-16 and/or HPV-18. There was also an upward trend in the prevalence of HR HPV infections as the abnormality in cytology increased. The prevalence of HPV co-infection was 29.1% of HPV positive patients and declined from LSIL (18.2%) to HSIL (3.9%). CONCLUSIONS: Our study indicated that the burden of HPV infection among Iranian females was higher in comparison with previous estimates reported from Iran. Furthermore, higher prevalence of premalignant changes in Iranian women infected with HR HPV types, other than vaccine types, should be considered in immunization programs and development of population-specific HPV vaccines. This remarkable difference in prevalence of HPV types among previous studies, confirms our need to further investigations on epidemiology of HPV infection in Iran.

Expression of epidermal growth factor receptor as a predictive factor for rectal cancer.

BACKGROUND: Expression of epidermal growth factor receptor is observed in 50 - 70% of colorectal carcinomas and is associated with poor prognosis. The objective of this study was to analyze whether epidermal growth factor receptor expression predicts tumor response and sphincter preserving in patients treated with preoperative chemoradiation therapy. METHODS: This study was conducted on 34 patients with locally-advanced rectal adenocarcinoma who were treated with preoperative chemoradiation therapy. The patients had histologically-proven adenocarcinoma of the rectum with the inferior margin of the tumor located no farther than 6 cm from the anal verge. Preoperative radiotherapy was delivered to the pelvis with 60CO to 50.4 Gy. All patients received simultaneous chemotherapy with 5-fluorouracil, 300 mg/m(2) IV infused over 24 hr during radiotherapy on days 1 - 5 every week; 28 patients received oxaliplatin 50 - 60 mg/m(2) weekly during radiotherapy. The patients were restaged by physical examination and pelvic CT, between four and six weeks later. Then, they were referred to a surgeon who was expert in gastrointestinal cancer surgery. Subsequently, postsurgical specimen was histopathologically examined and graded according to the Mandard criteria for assessment of pathologic response after neo-adjuvant chemoradiation. Immunohistochemistry for epidermal growth factor receptor was determined at the preradiation biopsy and was evaluated according to the extension and staining intensity. RESULTS: Fourteen (41%) out of 34 tumors were epidermal growth factor receptor positive. Twenty (59%) patients responded to pelvic preoperative chemoradiation. Sixteen (47%) patients achieved complete response with no residual tumor in the resected specimen; four (12%) were downstaged (partial response). Response to pelvic radiotherapy was observed in 80% of those negative for epidermal growth factor receptor and in 28% of those with positive epidermal growth factor receptor (P = 0.005). Only two of 14 positive epidermal growth factor receptor patients achieved a complete response, while 14 of 20 of the negative epidermal growth factor receptor patients developed complete response. In our study, the sphincter preservation rate was 43% in positive epidermal growth factor receptor patients and 80% in those who did not express epidermal growth factor receptor (P = 0.036). CONCLUSION: Epidermal growth factor receptor expression in the diagnostic biopsy of locally-advanced rectal cancer treated with chemoradiation therapy may serve as an important predictor of complete response to preoperative treatment.