Performance of p16INK4a immunocytochemistry as a marker of anal squamous intraepithelial lesions.

BACKGROUND: Protein p16(INK4a) immunocytochemistry (ICCp16) has the potential to reveal lesions at risk of progression to anal cancer. This study examined measures of diagnostic validity of ICCp16 in HIV-positive patients treated at the Tropical Medicine Foundation of Amazonas in the coloproctology outpatient clinic. METHODS: One hundred ninety HIV-positive patients were consecutively enrolled in 2007 and 2008. All patients underwent anal cytologic sampling to perform ICCp16 in conventional and GluCyte (Synermed International, Westfield, Indiana and S¸ao Paulo, Brazil) smears and also for genotyping of human papillomavirus (HPV). Patients were then subjected to anal biopsies monitored by high-resolution anoscopy. Hematoxylin-eosin and immunoperoxidase p16 (clone 6H12) stains were performed in slides with biopsied and cytological specimens, respectively. HPV genotyping on anal scrapings was performed by a polymerase-chain reaction (PCR)-based method. The immunochemical findings were compared with histopathological and PCR results in contingency tables and analyzed by nonparametric tests. Measures of diagnostic validity of ICCp16 were calculated. Statistical significance was set at P ≤ .5. RESULTS: There was no statistically significant association between the immunochemical results (conventional or GluCyte smears) and histopathological or HPV genotyping findings (P > .05). In the best scenario, ICCp16 presented 31% sensitivity and 81% specificity for the diagnosis of anal squamous intraepithelial lesion (ASIL) and 30% and 66%, respectively, for the diagnosis of infection with high-risk HPV. CONCLUSIONS: There was no association between ICCp16 results and histopathological findings nor between ICCp16 and HPV genotyping. ICCp16 showed poor sensitivity and moderate specificity for the diagnosis of ASIL or high-risk HPV.

High-resolution anoscopy in the diagnosis of anal cancer precursor lesions in renal graft recipients.

BACKGROUND: Renal graft recipients are one of the population groups known to be at high risk of developing anal cancer. This study investigated the presence of subclinical anal squamous intraepithelial lesions and the diagnostic ability of high-resolution anoscopy in detecting these lesions in renal graft recipients followed-up in Manaus. METHODS: In a cross-sectional study, 50 renal graft recipients were interviewed and submitted to high-resolution anoscopy with biopsies of acetowhite lesions or of the anal transition zone mucosa when acetowhitening was absent. Considering the histopathological reports of the examined anal specimens as the gold standard, the diagnostic validation and precision measures of high-resolution anoscopy were calculated as well as the prevalence of anal squamous intraepithelial lesions in the studied population. RESULTS: In 42 renal graft recipients with satisfactory histopathological readings, prevalence of anal squamous intraepithelial lesions or condyloma acuminatum (ASIL-ACU) was 23.81%. Sensitivity of high-resolution anoscopy was 100%; specificity, 65.63%; positive predictive value, 47.62%; negative predictive value, 100%; and kappa coefficient, 0.48. CONCLUSIONS: With a prevalence of 23.81% of subclinical ASIL-ACU lesions, the studied renal graft recipients had all these lesions detected by high-resolution anoscopy, notwithstanding most anal transition zone acetowhitened biopsied areas did not reveal histopathological aspects of anal cancer precursor lesions or condyloma acuminatum. Therefore, greater experience with the diagnostic tool was felt necessary to enhance its positive predictive value, specificity and diagnostic precision.

Colecistectomia agulhascópica: aspectos técnicos e resultados iniciais

The authors describe the technique they employed to perform needlescopic cholecystectomies in the Núcleo de Hospital de Aeronáutica de Manaus, from September 1997 to May 1999. A complete videolaparoscopic set of equipment was used in the procedure in association to an extra videocapture set for the microlaparoscope (video monitor, microcamera and light source). The procedure is mainly performed with the needlescopic instruments (MiniSite®) inserted in the epigastric, upper right abdominal quadrant and right flanc 2mm trocar sleeves, introduced through the anterior abdominal wall with 10 mm umbilical videolaparoscopic guidance. The microlaparoscope was employed through the epigastric port to monitor the 10 mm clip applier, inserted through the umbilical port to ligate the cistic elements. Likewise, it was employed to monitor gallbladder removal from the abdominal cavity through the umbilical wound. The 2 mm skin wounds were closed with sterile surgical tape. A total of 83 patients (11 males, 72 females), ranging from 17 to 87 years of age, with gallbladder diseases were operated. There was no patient selection in the study but most of the cases (89.2%) did not present inspissated gallbladder walls. The mean operative time was 92 ± 21 min and the average time of hospitalization was 16 h. The main peroperative incident observed was gallbladder puncture with bile leakage to the abdominal cavity (41%), which was considered due to the surgical teams learning curve in the method. Vomits were the main postoperative complication (51.8%) and there was no instance of wound infection. The complete method of needlescopic cholecystectomy was employed in 82% of the patients; in 6% of the patients, a 5 or 10 mm portal had to be put in place of one of the 2 mm to deal with thick walled gallbladders or to correct image problems encountered with the 2 mm laparoscope; in another 6% of the patients, an extra 10 mm suprapubic portal was employed to receive the 10 mm laparoscope when the umbilical portal was used with 5 and 10 mm instruments (in these cases the 2 mm laparoscope was not available due to fiberoptic deterioration). In 3.6 % of the surgeries, the needlescopic method had to be converted to the usual videolaparoscopic one (with two 5 mm and two 10 mm portals). Two operations had to be converted to conventional cholecystectomies (one due to equipment failure and the other due to a solid block of inflammatory adhesions to the hepatic hilar structures). The authors conclude that needlescopic cholecystectomies are feasible, demand the surgical team to go through a new learning curve period and are responsible for a longer operative time due to peculiarities of the instruments and equipment involved.

Os autores descrevem a técnica que utilizaram para a realização da colecistectomia agulhascópica no Núcleo de Hospital de Aeronáutica de Manaus, de setembro de 1997 a maio de 1999, e os resultados iniciais obtidos em 83 pacientes (11 do sexo masculino e 72 do feminino, com idades variando de 17 a 87 anos) portadores de doenças da vesícula biliar. Empregaram, além de um equipamento completo de videolaparoscopia, um equipamento acessório composto de um monitor de vídeo, uma microcâmera, com seu processador de imagens, e uma fonte de luz, tudo para o laparoscópio de 1,7 mm MiniSite®. A operação foi realizada principalmente sob monitoramento videolaparoscópico de 10 mm pelo portal umbilical e por meio de três portais de 2 mm (epigástrico, hipocôndrio direito e flanco direito). Utilizou-se o videolaparoscópio de 2 mm pelo portal epigástrico quando se procedeu às ligaduras císticas, ocasião em que o laparoscópio de 10 mm umbilical era substituído pelo aplicador de clipes de 10 mm. Da mesma forma, a vesícula foi retirada da cavidade abdominal pelo portal umbilical sob monitoramento videolaparoscópico de 1,7 mm epigástrico. A maioria dos casos operados (89,2%) não apresentava espessamento da parede vesicular. O tempo cirúrgico médio do procedimento foi de 92 ± 21 min e o de internação foi de 16 h. A principal intercorrência operatória foi a perfuração da vesícula biliar (41%), atribuída à curva de aprendizado no método por que passa a equipe. Vômitos foram a principal complicação pós-operatória (51,8%), não tendo havido infecção de ferida operatória. Oitenta e dois por cento dos casos puderam ser terminados pelo método agulhascópico puro, enquanto em 6% e 3,6%, respectivamente, houve necessidade de trocar um dos portais de 2 mm por um de 5 ou de 10 mm e de converter o procedimento para videolaparoscopia usual. Em 6% dos casos, por problemas de imagem com o microlaparoscópio, realizou-se o procedimento agulhascópico com a assistência de um portal suprapúbico de 10 mm. Dois casos (2,4%) tiveram que ser convertidos para laparotomia convencional, um por problemas operacionais com o equipamento e outro por dificuldades técnicas transoperatórias. Os autores concluem ser o procedimento agulhascópico factível, demandar uma nova curva de aprendizado por parte da equipe e ser demorado em virtude das características de seus instrumental e equipamento.