The aromatase inhibitors (plus ovarian function suppression) in premenopausal breast cancer patients: ready for prime time?

The magic of a methyl group: Biochemistry at the service of medicine

A carbon-carbon linkage is created when a methyl group is implanted on dUMP, thus resulting in the formation of dTMP by thymidylate synthase. The methyl group is deleted by aromatase when androgens are converted to estrogens. The methyl group is rearranged with the help of vitamin B12 in the isomerization of methylmalonyl-CoA to succinyl-CoA. S-adenosylmethionine (SAM) serves as the universal methyl donor involved in the biosynthesis of adrenaline and creatine(phosphate). It also interferes with the 5'-mRNA capping and the degradation of catecholamines (i.e. adrenaline, noradrenaline). Cholesterol could be viewed as a conglomeration of methyl groups. Finally, as part of valine, two methyl functions participate in the origin of one of the most frequent hereditary diseases on earth, sickle cell anemia.

The phytoestrogenic Cyclopia extract, SM6Met, increases median tumor free survival and reduces tumor mass and volume in chemically induced rat mammary gland carcinogenesis

SM6Met, a phytoestrogenic extract of Cyclopia subternata indigenous to the Western Cape province of South Africa, displays estrogenic attributes with potential for breast cancer chemoprevention. In this study, we report that SM6Met, in the presence of estradiol, induces a significant cell cycle G0/G1 phase arrest similar to the selective estrogen receptor modulator, tamoxifen. Furthermore, as a proof of concept, in the N-Methyl-N-nitrosourea induced rat mammary gland carcinogenesis model, SM6Met increases tumor latency by 7days and median tumor free survival by 42 days, while decreasing palpable tumor frequency by 32%, tumor mass by 40%, and tumor volume by 53%. Therefore, the current study provides proof of concept that SM6Met has definite potential as a chemopreventative agent against the development and progression of breast cancer.

Navigating the Challenges of Endocrine Treatments in Premenopausal Women with ER-Positive Early Breast Cancer

Endocrine therapy is a key component of adjuvant treatment for premenopausal patients with endocrine-responsive tumors. It is commonly well tolerated, although side effects are a main concern in the selection of treatment options. Tamoxifen is still considered an adequate endocrine therapy in a large group of premenopausal patients (e.g. lower-risk patient, presence of co-morbidities, patient preference). Results of the SOFT and TEXT trials addressing new adjuvant endocrine treatment options in premenopausal patients were recently presented. Overall, in the SOFT study the premenopausal population did not benefit from the addition of ovarian function suppression (OFS). Nevertheless, for women at sufficient risk of recurrence to receive adjuvant chemotherapy and who maintained premenopausal estradiol, the addition of OFS to tamoxifen reduced the risk of recurrence. The magnitude of the effect was larger in younger patients. Moreover, in the SOFT and TEXT trials, adjuvant treatment with exemestane plus OFS, as compared with tamoxifen plus OFS, significantly improved disease-free survival, breast cancer-free interval and distant disease-free survival. However, premenopausal patients include heterogeneous subsets of women and tumors where costs and benefits of adjuvant endocrine therapy should be properly weighted. Issues specific for premenopausal patients, related to desire for pregnancy, family planning, safety, quality of life and subjective side effects, should be a priority in the therapeutic algorithm. Therefore, selecting the best-tolerated agent can enhance adherence to therapies and reduce the impact on quality of life and health status for these younger patients.

Is Estradiol Monitoring Necessary in Women Receiving Ovarian Suppression for Breast Cancer?

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors’ suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

A 36-year-old premenopausal woman had been diagnosed with stage III breast cancer. After an initial biopsy confirmed breast cancer, she underwent mastectomy and axillary node dissection for a left-sided breast cancer, measuring 7 cm. The tumor had lobular histology and was considered grade 2 of 3. Metastatic carcinoma was identified in 10 of 13 axillary nodes. Immunohistochemical studies showed that the tumor was strongly positive for estrogen and progesterone receptor expression and had a Ki-67 score of 15% (> 20% is considered high according to a Swedish quality control study and the St Gallen Expert Consensus). 1 , 2 There was no amplification of the HER2/neu gene. Staging scans were negative for metastatic disease. In the adjuvant setting, she received three cycles of anthracycline-cyclophosphamide combination chemotherapy followed by three cycles of taxane chemotherapy and then locoregional radiotherapy. After completion of chemotherapy, she developed amenorrhea. As adjuvant endocrine therapy, she began monthly goserelin administration to achieve ovarian function suppression (OFS), in combination with the aromatase inhibitor (AI) exemestane. She experienced menopausal symptoms including hot flashes, vaginal dryness, and sexual dysfunction. After two monthly treatments with goserelin and exemestane, a sensitive assay for serum estradiol was checked and returned at 16 pg/mL (61 pmol/L); postmenopausal range for sensitive assay is less than 15 pg/mL (< 50 pmol/L). The patient has now been referred to our unit to discuss further management.

One-Year Neoadjuvant Endocrine Therapy in Breast Cancer

The evaluation of the effects of 1-year endocrine therapy (NET) was aimed at. A retrospective analysis of 42 cases with 46 stage II-III invasive, hormone receptor-positive, HER2-negative breast cancers was performed. One-year NET was planned with letrozole (n = 33, postmenopausal group), or with goserelin plus letrozole (n = 7) or with goserelin plus tamoxifen (n = 2) (premenopausal group). Surgery was performed in accordance with the initial stage and the response to therapy. With regard to the tumor remaining in the surgical specimen, risk groups were constructed: Group 1: stage 0, pathological complete regression (pCR); Group 2: stages IA-IIA; Group 3: stages ≥ IIB + cases with clinical progression. Due to local progression, NET was replaced by neoadjuvant chemotherapy in three patients (four tumors). In two postmenopausal patients, letrozole was replaced by tamoxifen because of the insufficient treatment effect. In 19/42 cases, breast-conserving surgery was performed. Within Group 1, there was no cancer in four cases, while only DCIS remained in 2 (pCR: 13 %); Groups 2 and 3 comprised 25 and 15 cases, respectively. The likeliness of a good response (Groups 1 and 2 vs. Group 3) to NET was increased by 7 % for every 1 % increase of the expression of ER (OR = 1.070; 95 % CI: 1.007-1.138, p = 0.029). Progression-free survival differed according to treatment response (p = 0.001). The post-therapy Ki67 value of ≤ 15 % had only a marginal effect on survival. No other associations were detected between the tumor characteristics and the therapeutic response or survival. Long-duration NET is effective and safe in cases of hormone-sensitive breast cancer.