Critical review of current treatment strategies for advanced hormone insensitive breast cancer

Recursive Partitioning Analysis of Prognostic Factors for Patients with Four or More Intracranial Metastases Treated with Radiosurgery

The purpose of this study was to devise a new recursive partitioning analysis (RPA) of patients with four or more intracranial metastases treated with a single radiosurgery procedure to identify a class of patients with extended survival. 205 patients underwent Gamma Knife radiosurgery for four or more intracranial metastases (median = 5, range 4–18) during one session. The median total treatment volume was 6.8 cc (range 0.6–51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with WB-RT (46%), or after failure of WB-RT (38%). The median marginal radiosurgery dose was 16 Gy (range 12–20 Gy). RPA assessed the effects of age, Karnofsky >70, extracranial disease, visceral metastases, number of metastases, total treatment volume, history of breast and melanoma primaries on survival. The median overall survival after radiosurgery for all patients was 8 months. RPA identified a favorable subgroup of 78 patients (43% of the series) with a total treatment volume <7 cc and < 7 brain metastases (Class 1), with a median survival of 13 months. This subgroup's survival was significantly better (p <0.00005) than the remaining patients (Class 2) (n=111) with a median survival of 6 months. In conclusion, RPA of multiple brain metastasis patients identified 2 distinct cohorts of patients. Class 1 patients have a total treatment volume <7 cc and < 7 metastases (4–6) with favorable survival after Radiosurgery and Class 2 patients have a total treatment volume ≥ 7 cc and/or ≥ 7 metastases and have a significantly poorer survival.

Aldehyde dehydrogenase inhibitors: a comprehensive review of the pharmacology, mechanism of action, substrate specificity, and clinical application

Aldehyde dehydrogenases (ALDHs) belong to a superfamily of enzymes that play a key role in the metabolism of aldehydes of both endogenous and exogenous derivation. The human ALDH superfamily comprises 19 isozymes that possess important physiological and toxicological functions. The ALDH1A subfamily plays a pivotal role in embryogenesis and development by mediating retinoic acid signaling. ALDH2, as a key enzyme that oxidizes acetaldehyde, is crucial for alcohol metabolism. ALDH1A1 and ALDH3A1 are lens and corneal crystallins, which are essential elements of the cellular defense mechanism against ultraviolet radiation-induced damage in ocular tissues. Many ALDH isozymes are important in oxidizing reactive aldehydes derived from lipid peroxidation and thereby help maintain cellular homeostasis. Increased expression and activity of ALDH isozymes have been reported in various human cancers and are associated with cancer relapse. As a direct consequence of their significant physiological and toxicological roles, inhibitors of the ALDH enzymes have been developed to treat human diseases. This review summarizes known ALDH inhibitors, their mechanisms of action, isozyme selectivity, potency, and clinical uses. The purpose of this review is to 1) establish the current status of pharmacological inhibition of the ALDHs, 2) provide a rationale for the continued development of ALDH isozyme-selective inhibitors, and 3) identify the challenges and potential therapeutic rewards associated with the creation of such agents.

Weekly administration of docetaxel and paclitaxel in metastatic or advanced breast cancer

The taxanes docetaxel (Taxotere; Aventis Pharmaceuticals Inc., Bridgewater, NJ, http://www.aventispharma-us.com) and paclitaxel (Taxol; Bristol-Myers Squibb, Princeton, NJ, http://www.bms.com) have significant clinical activity in metastatic breast cancer. A number of clinical trials have evaluated the tolerability and efficacy of weekly taxane administration to optimize the benefit-to-risk ratio in metastatic breast cancer. Single-agent studies with docetaxel and paclitaxel in metastatic breast cancer show clinically significant antitumor activity even in advanced, heavily pretreated, resistant, and/or refractory disease. This activity is also evident with taxane-based combination regimens. Severe hematologic and nonhematologic toxicities are infrequent, with other toxicities noted based on the dose and weekly regimen selected. Weekly docetaxel and paclitaxel regimens represent valuable therapeutic options for women with metastatic breast cancer and have entered evaluation as part of adjuvant therapy for this disease.

Stereotactic radiosurgery for four or more intracranial metastases

PURPOSE

To evaluate the outcomes after a single stereotactic radiosurgery procedure for the care of patients with 4 or more intracranial metastases.

METHODS AND MATERIALS

Two hundred five patients with primary malignancies, including non-small-cell lung carcinoma (42%), breast carcinoma (23%), melanoma (17%), renal cell carcinoma (6%), colon cancer (3%), and others (10%) underwent gamma knife radiosurgery for 4 or more intracranial metastases at one time. The median number of brain metastases was 5 (range, 4-18) with a median total treatment volume of 6.8 cc (range, 0.6-51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with whole brain radiotherapy (46%) or after failure of whole brain radiotherapy (38%). The median marginal radiosurgery dose was 16 Gy (range, 12-20 Gy). The mean follow-up was 8 months.

RESULTS

The median overall survival after radiosurgery for all patients was 8 months. The 1-year local control rate was 71%, and the median time to progressive/new brain metastases was 9 months. Using the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) classification system, the median overall survivals for RPA classes I, II, and III were 18, 9, and 3 months, respectively (p < 0.00001). Multivariate analysis revealed total treatment volume, age, RPA classification, and marginal dose as significant prognostic factors. The number of metastases was not statistically significant (p = 0.333).

CONCLUSION

Radiosurgery seems to provide survival benefit for patients with 4 or more intracranial metastases. Because total treatment volume was the most significant predictor of survival, the total volume of brain metastases, rather than the number of metastases, should be considered in identifying appropriate radiosurgery candidates.

Survival of metastatic breast carcinoma patients over a 20-year period

BACKGROUND

The expectation of improvement in patient survival with administration of new chemotherapy agents for metastatic breast carcinoma (MBC) is not consistently supported by data from clinical trials, which are often underpowered and have not detected moderate survival advantage. The aim of this study was to evaluate the impact of new agents on prognosis of MBC patients enrolled in clinical trials of first-line chemotherapy.

METHODS

Between 1983 and 2001, 640 MBC patients were entered into 6 consecutive trials; the present analysis was limited to patients. The date of diagnosis of metastatic breast disease was used to define 5 arbitrarily chosen 3-year time cohorts, 1983-1986, 1987-1989, 1992-1994, 1995-1997, and 1998-2001. Multivariate proportion of hazard (PH) models were used to evaluate changes in overall survival (OS) and progression-free survival (PFS) over time and to detect changes associated with the use of taxanes, while adjusting for differences in baseline factors among 5 cohorts.

RESULTS

Patient characteristics were evenly distributed across the 5 cohorts. Median OS was 18 months, 17.2 months, 19.2 months, 26.1 months, and 23.6 months, respectively, in cohorts 1983-1986, 1987-1989, 1992-1994, 1995-1997, 1998-2001 (P < 0.0001). Age, performance status, relapse-free survival, type of adjuvant treatment, metastatic site, and taxane first-line chemotherapy were all associated with survival. These data failed to provide an indication of temporal trend and suggested a reduction in hazard of death in two cohorts (1995-1997 and 1998-2001) where taxane was added to first-line chemotherapy.

CONCLUSIONS

The analysis provided evidence of improvement in prognosis of MBC patients that was associated with use of modern chemotherapeutic agents independent of time.

α-Tocopheryloxybutyric acid enhances necrotic cell death in breast cancer cells treated with chemotherapy agent

The overexpression of HER-2 receptor contributes to malignant transformation of breast cancer cells. We have reported that alpha-tocopheryloxybutyric acid (TE), non-antioxidative vitamin E ether derivative inhibits the activation of HER-2 receptor. The present study was undertaken to estimate if TE could act as a useful anti-cancer agent against a breast cancer cell overexpressing HER-2 receptor (MDA-MB-453 cell line) in combination with a conventional chemotherapy agent, adriamycin (ADR). TE enhanced cytotoxic effect of ADR against the human breast cancer cell at low doses less than IC(50). The enhancing effect was mainly dependent on the elevation of necrotic-like cell death but not apoptotic cell death. In conjugation with this event, the inactivation of HER-2 receptor in the breast cancer cell was caused by the combination of TE with ADR. These results suggest that TE enhances necrotic-like cell death in the breast cancer cells and that the cell death relates to the inactivation of HER-2 receptor in the breast cancer cells.