A prediction model for breast cancer recurrence after adjuvant hormone therapy.

Hormone therapy with tamoxifen has long been the established adjuvant treatment for node-positive, estrogen-receptor-positive breast cancer in postmenopausal women. Since 30-40% of these patients fail to respond, reliableoutcome prediction is necessary for successful treatment allocation. Using pathobiological variables (available in mostclinical records: tumor size, nodal involvement, estrogen and progesterone receptor content) from 596 patients recruitedat a comprehensive cancer center, we developed a prediction model which we validated in an independent cohort of 175patients recruited at a general hospital. Calculated at 3 and 4 years of follow-up, the discrimination indices were 0.716[confidence limits (CL) 0.641, 0.752] and 0.714 (CL 0.650, 0.750) for the training data, and 0.726 (CL 0.591, 0.769) and0.677 (CL 0.580, 0.745) for the testing data. Waiting for more effective approaches from genomic and proteomic studies, amodel based on consolidated pathobiological variables routinely assessed at relatively low costs may be considered as thereference for assessing the gain of new markers over traditional ones, thus substantially improving the conventional use ofprognostic criteria.

Angiogenesis sustains tumor dormancy in patients with breast cancer treated with adjuvant chemotherapy.

Experimental studies performed in Folkman laboratories suggest that angiogenesis is involved in the biology of tumor dormancy. We determined the vascular index in a series of 190 women operated of node-positive invasive breast cancer treated with adjuvant chemotherapy (CMF schedule) and we studied the relationship between vascularity of primary tumors with the behaviour in time of metastasis. The study of the hazard function of recurrence (in any site) was performed resorting to a generalized linear modelling approach with a binominal error according to Efron. A total of 80 cases developed recurrences during the period of observation. We found that the hazard function of metastasis in time presented two peaks of incidence at 20 and 60 months, respectively. We also plotted the curves of the hazard function by considering three values of microvessel counts corresponding to the quartiles of their distribution. The risk of first recurrence was associated with vascular index, and the patients of the third quartile of distribution of microvessels had the highest risk. In the final full model for the risk of recurrence at 5 years vascular index provided the highest prognostic contribution followed by the number of involved axillary lymph nodes. The observation that the patients with highly angiogenic tumors are at high risk of recurrence coupled with the identification of the second peak of incidence after 5 years which was also mainly sustained by angiogenic tumors suggest that a fraction of breast cancers promote metastasis after a period of tumor dormancy. The clinical and therapeutic implications of our results are discussed.

Response to cyclophosphamide, methotrexate, and fluorouracil in lymph node-positive breast cancer according to HER2 overexpression and other tumor biologic variables.

PURPOSE: There is considerable interest in biologic markers able to predict the response of cancer patients to therapy. HER2 overexpression is a potential indicator of responsiveness to doxorubicin and paclitaxel and of unresponsiveness to tamoxifen in breast carcinoma patients. However, the significance of HER2 overexpression in responsiveness to cyclophosphamide, methotrexate, and fluorouracil (CMF) has remained unclear. In this study, we investigated this issue in the 386 breast cancer patients in the first CMF controlled clinical trial with a 20-year follow-up. PATIENTS AND METHODS: Node-positive breast carcinoma patients were randomly assigned to receive either no further treatment after radical mastectomy (179 women) or 12 monthly cycles of adjuvant CMF chemotherapy (207 women). Overexpression of HER2 and the status of other tumor variables was assessed by immunohistochemistry in at least 324 (84%) of the 386 patients. Statistical analyses were performed to assess the efficacy of CMF treatment for the subgroups defined by HER2 and the status of other variables using a Bayesian approach. The end points considered were relapse-free survival (RFS) and cause-specific survival (CSS). RESULTS: Bayesian analysis of the treatment effect for HER2 and other variables indicated a clinical benefit from CMF treatment in all subgroups defined according to variables status. In particular regarding HER2 status, Bayesian estimates of RFS hazard ratios were equal to 0.484 and 0.641 and estimates of CSS hazard ratios were equal to 0.495 and 0.730 for HER2-positive and -negative tumors, respectively. CONCLUSION: CMF treatment showed a clinical benefit in the considered subgroups, defined according to HER2 and other tumor variables status. Patients with HER2-positive or HER2-negative tumors benefit from CMF treatment, and the poor prognosis associated with the HER2 overexpression in the untreated group could be completely overcome by the chemotherapy treatment.

Ecotoxicological soil evaluation by FETAX.

The frog embryo teratogenesis assay-Xenopus (FETAX) is a powerful and flexible bioassay that makes use of the embryos of the anuran Xenopus laevis. FETAX satisfies the requirements of low cost, reliability and reproducibility and, thanks to its three endpoints (i.e., mortality, teratogenicity and growth inhibition) can detect the xenobiotics that affect embryonic development. In this paper, we have used FETAX to evaluate samples of soils collected in an oil-contaminated area. Embryos were exposed directly to the soil to be tested. Particular attention was devoted to provide a statistical procedure for analysing mortality and malformation data as well as growth retardation.

Relationship between steroid receptors (as continuous variables) and response to adjuvant treatments in postmenopausal women with node-positive breast cancer.

In current clinical practice for breast cancer patients, estrogen (ER) and progesterone receptor (PgR) concentrations, quantified by the dextran-coated charcoal assay, are categorized by an arbitrary cutoff into a negative or positive status. However, although the results obtained with this approach are easy to interpret, such a representation could oversimplify the relationship between ER and PgR content and patient outcome and imply an assumption of monotonicity, which is generally expected but rarely proven. We evaluated the relationship between ER and PgR content (considered on a continuous scale) and clinical outcome, using a flexible statistical model, in a group of postmenopausal patients with N-positive operable tumors who were submitted to surgery and different adjuvant treatments (tamoxifen or CMF). Univariate analysis indicated that in the tamoxifen-treated group, ER level, number of metastatic nodes (pN) and age, but not PgR, were significant indicators of clinical outcome (p = 0.032, p = 0.021 and p = 0.029, respectively). Multivariate analysis indicated that in this group of patients there was no interaction between variables, and in the final model for disease-free survival (DFS) only ER and pN were retained with an overall predictive ability of the regression model of 0.723, as evaluated by Harrell's c. However, pN markedly contributed to the predictive ability of the model with respect to ER, since a marked decrease in Harrell's c statistic (c = 0.582) was observed when pN was removed from the model. In the CMF-treated group, only pN affected clinical outcome. When the estimated DFS curves obtained from the final Cox regression models were plotted according to four values of ER (in the tamoxifen-treated group) or three values of pN (in the CMF-treated group) we observed that in the tamoxifen-treated group patients with an ER concentration equal to 0 fmol/mg cytosol protein had the worst prognosis, whereas a marked improvement of the expected DFS was observed for patients with a low but detectable ER level (generally classified as ER-negative because falling below the conventional cutoff value of 10 fmol/mg cytosol protein). Our results seem to suggest that the use of steroid receptor concentrations on a continuous scale, instead of dichotomous "status", is to be preferred in the choice of adequate therapeutic strategies.

Tumor angiogenesis predicts clinical outcome of node-positive breast cancer patients treated with adjuvant hormone therapy or chemotherapy.

PURPOSE: Experimental studies suggest that angiogenesis is necessary for breast cancer progression and metastasis and that it may play a role in responsiveness to some chemotherapeutic agents and to tamoxifen. To investigate whether angiogenesis predicts the clinical outcome of patients with node-positive breast cancer, we determined intratumoral microvessel density in a series of patients treated with either adjuvant hormone therapy (n=84) or chemotherapy (n= 107). PATIENTS AND METHODS: We monitored 191 patients for a median of 62 months. Intratumoral microvessel density was measured using light microscopy, and microvessels were immunostained using the anti-CD31 antibody. Microvessels were carefully counted (per 200x field) in the most vascularized area of each tumor. The results of intratumoral microvessel density were analyzed by both univariate and multivariate statistical analysis and were correlated with clinical outcome. RESULTS: In univariate analysis, intratumoral microvessel density was significantly associated with relapse-free survival and overall survival, both in patients who received adjuvant hormone therapy and those who received chemotherapy. In the group treated with adjuvant hormone therapy, estrogen receptor status was also predictive for both relapse-free and overall survival. The number of involved nodes was predictive for overall survival. In patients treated with adjuvant chemotherapy, the number of involved nodes, tumor size, and progesterone receptor status were significantly predictive for relapse-free and overall survival. Multivariate analysis showed that intratumoral microvessel density was the strongest independent predictor of outcome in both treatment groups. CONCLUSIONS: Intratumoral microvessel density is an independent predictive indicator in node-positive breast cancer patients treated with either adjuvant chemotherapy or adjuvant hormone therapy. Assessment of tumor angiogenesis may therefore be useful in selection of those patients who are more likely to benefit from conventional adjuvant therapies (i.e., those with minimally vascularized tumors) from those with highly vascularized and more aggressive tumors, for whom novel forms of systemic therapy are advocated.

Expression of bcl-2 protein predicts efficacy of adjuvant treatments in operable node-positive breast cancer.

The proto-oncogene bcl-2 encodes a protein that inhibits apoptosis, a common mechanism of cell death caused by hormone and chemotherapy. We have analyzed bcl-2 protein expression by immuno-cytochemistry in primary node-positive breast cancers in two groups of patients (for a total of 180 cases). One group received adjuvant hormone therapy, the other chemotherapy (cyclophosphamide, methotrexate, and fluorouracil), and both groups were followed for a median time of 63 months. We compared our findings with conventional clinicopathological indicators [menopausal status, number of axillary nodes, histological grade, tumor size and type, estrogen receptor (ER), and progesterone receptor] and with p53 protein expression. bcl-2 protein was present in 65% of the carcinomas (117/180) and it was significantly associated with ER and progesterone receptor and inversely associated with p53 in both the groups of patients treated with adjuvant chemotherapy and tamoxifen. In patients treated either with adjuvant chemotherapy or tamoxifen, relapse-free survival at 5 years was significantly better among patients with bcl-2-positive tumors than in those with bcl-2 negative ones (P = 0.05 and 0.02, respectively). As far as overall survival is concerned, patients with bcl-2-positive tumors had a significantly better outcome in the group treated with adjuvant chemotherapy (P = 0.03). Multivariate analyses were performed for the two treatment groups. In the group treated with tamoxifen, lack of expression of ER and of bcl-2 was the only significant and independent predictor for poor relapse-free survival (P < 0.01). A number of nodes above 3 was the only significant and independent predictor for poor overall survival (P < 0.01). In the cyclophosphamide-methotrexate-fluorouracil-treated group, bcl-2 absence was significant for poor overall survival (P = 0.02) as well as a number of nodes above 3 (P = 0.04) and a tumor size above 2 cm (P = 0.05). For poor relapse-free survival only a number of nodes above 3 (P < 0.01) and progesterone negativity (P = 0.02) were significant and independent predictors of a higher probability of relapse. Thus, in contrast to in vitro data on drug resistance, bcl-2 expression was associated with better outcomes in patients treated with hormone and chemotherapy. Overall, these results suggest that expression of bcl-2 protein and the number of metastatic lymph nodes are independent features predictive of clinical outcome in patients with node-positive breast cancer, irrespective of the type of adjuvant treatment. The determination of bcl-2 protein may prove to be a useful tool to distinguish patients for whom conventional forms of adjuvant therapy are beneficial from those with bcl-2 negative and ER-negative tumors for whom novel therapeutic strategies are needed.

Adjuvant chemotherapy with fluorouracil and CCNU in colon cancer. Results of a multicentric randomized study.

To establish the effectiveness of adjuvant chemotherapy in patients with colon cancer after radical surgery, from 1980 to December 1983, 263 patients were randomized in a multicentric study to no further treatment (131 patients) or to a combination of fluorouracil (5-FU) (400 mg/m2 i.v., days 1-5) and lomustine (CCNU) (100 mg/m2 per os on day 5) every 6 weeks for 9 cycles (132 patients). The two groups were well balanced for age, sex, histology, tumor and nodal extent. Chemotherapy was not given to 30 of the 132 randomized patients, and of 98 treated patients only 38 completed the entire protocol. Analysis, as intention to treat, at 54 months did not show any significant difference between the two treatment groups in terms of relapse-free survival (surgery alone, 74.5%; surgery + adjuvant chemotherapy, 70.9%; p = 0.91). In contrast, a significant difference was observed in overall survival (surgery alone, 78.8%; surgery + adjuvant chemotherapy, 60.8%; p = 0.04). The sites of relapse were identical in the two treatment arms. In conclusion, from this study it appears that adjuvant chemotherapy with 5-FU and CCNU seems to have no efficacy in the cure rate of colon cancer patients.