Sentinel node biopsy in breast cancer: results in a large series

Sentinel lymph node biopsy (SLNB) is an appropriate method for the evaluation of axillary status in cases of early breast cancer. We report our experience in treating cases evaluated using SLNB. We analyzed a total of 1192 cases assessed by means of SLNB from July 1999 to December 2007. SLNB processing was successfully completed in 1154 cases with the use of blue dye or radiolabeled 99mTc-Dextran-500, or both. Of these 1154 patients, 857 were N0(i-) (no regional lymph node metastasis, negative immunohistochemistry, IHC), 96 were N0(i+) (no regional lymph node metastasis histologically, positive IHC, no IHC cluster greater than 0.2 mm) and 201 were N1mi (greater than 0.2 mm, none greater than 2.0 mm). Most of the tumors (70 percent) were invasive ductal carcinomas and tumors were staged as T1 in 770 patients (65 percent). A total of 274 patients underwent SLNB and axillary dissections up to April 2003. The inclusion criteria were tumor size equal to or less than 3 cm in diameter, no clinically palpable axillary lymph nodes, no neoadjuvant therapy. In 19 cases, the SLN could not be identified intraoperatively. A false-negative rate of 11 percent and a negative predictive value of 88.2 percent were obtained for the 255 assessable patients. The overall concordance between SLNB and axillary lymph node status was 92 percent. SLNB sensitivity for nodes was 81 percent and specificity was 100 percent. The higher sensitivity, specificity, accuracy, and lower false-negative rates of SLNB suggest that this method may be an appropriate alternative to total axillary dissection in early breast cancer patients.

Lipossarcomas abdominais / Abdominal liposarcomas

Lipossarcomas àbdominais constituem um grupo de tumores pouco freqüentes e, por isso, os princípios de tratamento desses tumores baseiam-se em experiências acumuladas no passado em séries retrospectivas. OBJETIVO. Apresentar sete casos de lipossarcomas abdominais de grandes proporçöes e discutir os principais aspectos diagnósticos e terapêuticos desses tumores na atualidade.MÉTODOS. Foram estudados sete doentes operados com lipossarcoma abdominal em um período de dois anos e meio na Disciplina de Gastroenterologia Cirúrgica da Escola Paulista de Medicina. Foram coletados os principais aspectos clínicos, ultrasonográficos e tomográficos, bem como os achados cirúrgicos e histopatológicos decada caso. RESULTADOS. Os autores chamam a atençäo para a raridade desses tumoree para sua tendência, quando primários, a crescer localmente, sem invadir os tecidos ao seu redor ou metastizar a distância, e, quando recidivantes, a exibir maior multicentricidade e malignidade mais agressiva. Consideram a tomografia computadorizada e mais útil procedimento diagnóstico e descartam a necessidade de biópsia percutânea, dirigida ou näo, no pré-operatório. Ressaltam o papel fundamental da cirurgia excisional radical no tratamento desses tumores e chamam a atençäo para a importância da ressecçäo com margens de segurança adequadas, mesmo quepara tal haja necessidade de ressecçäo associada de vísceras. Consideram a radioterapia e a quimioterapia como métodos pouco eficazes, no momento, para o tratamento adjuvante desses tumores. CONCLUSÄO. É importante um seguimento acurado dospacientes operados, com a indicaçäo, quando necessário, de repetidas cirurgias de ressecçäo, mesmo paliativas (cirurgias citorredutoras), no sentido de melhoriana expectativa de sobrevida.

The effect of fasting and refeeding on oxygen consumption by rats

Oxygen consumption is usually measured on fasted animals to avoid the thermal effect of feeding. However, fasting itself may decrease oxyge consumption as a way of conserving energy. The present study was undertaken to determine how long the fasting period should be to avoid the thermal effect of feeding without promoting a further decrease in oxygen consumption by the activation of energy-conservation mechanisms. Oxygen consumption was also measured to evaluate the effect of refeeding after different fasting periods. There was a 16% decrease in oxygen consumption from 0 to 12 h fasting related to the thermal effect of feeding, followed by a less intense (12%) decrease from 12 to 48 h fasting resulting from the energy conservationn mechanism. During refeeding, oxygen consumption was higher during the first 30-min period than during the last 30-min period of the 1-h measurement, indicating the probable presence of a cephalic phase of postprandial thermogenesis. We conclude that 12-h fasting is the most appropriate period to avoid the thermal effect of feeding without significantly stimulating the energy conservation mechanism