The impact of PTEN tumor suppressor gene on acquiring resistance to tamoxifen treatment in breast cancer patients

Tamoxifen is a standard therapeutical treatment in patients with estrogen receptor positive breast carcinoma. However, less than 50% of estrogen receptor positive breast cancers do not respond to tamoxifen treatment whereas 40% of tumors that initially respond to treatment develop resistance over time. The underlying mechanisms for tamoxifen resistance are probably multifactorial but remain largely unknown. The primary aim of this study was to investigate the impact of PTEN tumor suppressor gene on acquiring resistance to tamoxifen by analyzing loss of heterozygosity (LOH) and immunohystochemical expression of PTEN in 49 primary breast carcinomas of patients treated with tamoxifen as the only adjuvant therapy. The effect of PTEN inactivation on breast cancer progression and disease outcome was also analyzed. Reduced or completely lost PTEN expression was observed in 55.1% of samples, while 63.3% of samples displayed LOH of PTEN gene. Inactivation of PTEN immunoexpression significantly correlated with the PTEN loss of heterozygosity, suggesting LOH as the most important genetic mechanism for the reduction or complete loss of PTEN expression in primary breast carcinoma. Most importantly, LOH of PTEN and consequential reduction of its immunoexpression showed significant correlation with the recurrence of the disease. Besides, our study revealed that LOH of PTEN tumor suppressor was significantly associated with shorter disease free survival, breast cancer specific survival and overall survival. In summary, our results imply that LOH of PTEN could be used as a good prognostic characteristic for the outcome of breast cancer patients treated with tamoxifen

Perioperative myocardial ischemia in coronary artery disease patients undergoing abdominal nonvascular surgery

BACKGROUND: The incidence of perioperative myocardial ischemia (PMI) is the highest in patients who have coronary artery disease, and it is the best predictor of intrahospital morbidity and mortality. OBJECTIVE: To identify predictors of PMI in patients who have coronary artery disease and are undergoing abdominal nonvascular surgery. METHODS: A prospective, observational, clinical study of 111 consecutive patients with angiographically verified coronary artery disease, scheduled for open abdominal nonvascular surgery, was conducted. Patients received general anesthesia and were monitored by continuous electrocardiogram during surgery and immediately postsurgery (72 h period) in the intensive care unit at the University Clinical Center (Belgrade, Serbia). All of the patients had 12-lead electrocardiography immediately after the surgery, on postoperative days 1, 2 and 7, and one day before discharge from hospital. The patients were monitored until the 30th postoperative day. RESULTS: A total of 24 predictors for PMI were analyzed. The Pearson's chi(2) test and a binomial logistic regression model were used for statistical analysis. A significant difference in the incidence of PMI was found in the coronary artery disease patients with an associated risk factor (14 of 24 risk factors) compared with those without the risk factor. In particular, a highly significant difference in the incidence of PMI was found in coronary artery disease patients with angina pectoris, compared with those without angina pectoris. CONCLUSION: Using the multivariate logistic regression analysis, angina pectoris was an independent predictor of PMI

Invasive inflammatory pseudotumor of the pelvis: A case report with review of the literature

Inflammatory pseudotumor (IPT) is a rare benign lesion of unknown etiology, which mimics malignant neoplasm and may arise from various organs. A 53-year-old woman was submitted to diagnostic evaluation because of bilateral, hydroureteronephrosis and oedema of the left leg after a 3-month history of fever of unknown origin. On bimanual vaginal and rectal examination, a mass was involving the uterus, parametria and mostly left adnexa, while the cervix appeared normal. Computed tomographic (CT) scan revealed a 13x10.5 cm mass in the pelvis, mostly at the place of the left adnexa, uterus and both parametria, also involving the surrounding tissues and producing bilateral hydroureteronephrosis. At laparotomy, a grey solid mass was seen, mainly involving the reproductive system. As no radical operation could be performed, the mass was only biopsied and histology showed an inflammatory pseudotumor. Antibiotic therapy was given for one month. Follow-up CT4 and 8 months after laparotomy showed local regression of IPT The last follow-up CT, 20 months after laparotomy, revealed no evidence of tumor. © 2009 Zerbinis Medical Publications