RESUMO
Gallbladder cancer is usually associated with gallstone disease, late diagnosis, unsatisfactory treatment, and poor prognosis. We report here the worldwide geographical distribution of gallbladder cancer, review the main etiologic hypotheses, and provide some comments on perspectives for prevention. The highest incidence rate of gallbladder cancer is found among populations of the Andean area, North American Indians, and Mexican Americans. Gallbladder cancer is up to three times higher among women than men in all populations. The highest incidence rates in Europe are found in Poland, the Czech Republic, and Slovakia. Incidence rates in other regions of the world are relatively low. The highest mortality rates are also reported from South America, 3.5-15.5 per 100,000 among Chilean Mapuche Indians, Bolivians, and Chilean Hispanics. Intermediate rates, 3.7 to 9.1 per 100,000, are reported from Peru, Ecuador, Colombia, and Brazil. Mortality rates are low in North America, with the exception of high rates among American Indians in New Mexico (11.3 per 100,000) and among Mexican Americans. The main associated risk factors identified so far include cholelithiasis (especially untreated chronic symptomatic gallstones), obesity, reproductive factors, chronic infections of the gallbladder, and environmental exposure to specific chemicals. These suspected factors likely represent promoters of carcinogenesis. The main limitations of epidemiologic studies on gallbladder cancer are the small sample sizes and specific problems in quantifying exposure to putative risk factors. The natural history of gallbladder disease should be characterized to support the allocation of more resources for early treatment of symptomatic gallbladder disease in high-risk populations. Secondary prevention of gallbladder cancer could be effective if supported by cost-effective studies of prophylactic cholecystectomy among asymptomatic gallstone patients in high-risk areas.
Assuntos
Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/genética , Colelitíase/complicações , Colelitíase/genética , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/prevenção & controle , Humanos , Fatores de RiscoRESUMO
The authors review the cases with smooth muscle tumors of the stomach (SMTS), excluding the leiomyomas, at the Mexico's General Hospital in a period of 5 years. They found 8 cases in women and 3 in men, with 51.3 years average. The average of evolution of symptoms was 5 months, prevailing: anaemia, digestive bleeding and abdominal pain. Barium radiology and endoscopy guided to the diagnosis. The tumors were located 7 at the fundus, 3 at the body and one at the gastric antrum. The size oscillated between 1.5-28 cm., average 8 cm. Endoscopic specimens were positive in 2/7 cases and cytologic samples were negative in all cases. Eight tumors were leiomyosarcomas (LMS) and 3 were leiomyoblastomas (LMB); the histologic criteria in order to differentiate them was based on the number of mitosis for 50 fields (50 csf), the size and their hypercellularity. A patient died before being operated. Two cases were subjected to emergency surgery, and died after that. In the cases treated with elective surgery the authors performed subtotal gastrectomy with major omentectomy in 4 and surgical resection of the tumor in the remaining 4 patients. The mortality rate for surgery was 27.2%.