Clinical Outcomes Following Letrozole Treatment according to Estrogen Receptor Expression in Postmenopausal Women: LETTER Study (KBCSG-006)

Purpose

In this trial, we investigated the efficacy and safety of adjuvant letrozole for hormone receptor (HR)-positive breast cancer. Here, we report the clinical outcome in postmenopausal women with HR-positive breast cancer treated with adjuvant letrozole according to estrogen receptor (ER) expression levels.

Methods

In this multi-institutional, open-label, observational study, postmenopausal patients with HR-positive breast cancer received adjuvant letrozole (2.5 mg/daily) for 5 years unless they experienced disease progression or unacceptable toxicity or withdrew their consent. The patients were stratified into the following 3 groups according to ER expression levels using a modified Allred score (AS): low, intermediate, and high (AS 3–4, 5–6, and 7–8, respectively). ER expression was centrally reviewed. The primary objective was the 5-year disease-free survival (DFS) rate.

Results

Between April 25, 2010, and February 5, 2014, 440 patients were enrolled. With a median follow-up of 62.0 months, the 5-year DFS rate in all patients was 94.2% (95% confidence interval [CI], 91.8–96.6). The 5-year DFS and recurrence-free survival (RFS) rates did not differ according to ER expression; the 5-year DFS rates were 94.3% and 94.1%in the low-to-intermediate and high expression groups, respectively (p = 0.6), and the corresponding 5-year RFS rates were 95.7% and 95.4%, respectively (p = 0.7). Furthermore, 25 patients discontinued letrozole because of drug toxicity.

Conclusion

Treatment with adjuvant letrozole showed very favorable treatment outcomes and good tolerability among Korean postmenopausal women with ER-positive breast cancer, independent of ER expression.

Trial Registration

ClinicalTrials.gov Identifier: NCT01069211

Efficacy of health coaching and a web-based program on physical activity, weight, and distress management among cancer survivors: A multi-centered randomised controlled trial

OBJECTIVES

To investigate the efficacy of health coaching and a web-based program on survivor physical activity (PA), weight, and distress management among stomach, colon, lung and breast cancer patients.

METHODS

This randomised, controlled, 1-year trial conducted in five hospitals recruited cancer survivors within 2 months of completing primary cancer treatment who had not met ≥1 of these behavioural goals: (i) conducting moderate PA for at least 150 minutes/week or strenuous exercise for over 75 minutes per week or, in the case of lung cancer patients, low or moderate intensity exercise for over 12.5 MET per week, (ii) maintaining normal weight, and (iii) attaining a score >72 in the Post Traumatic Growth Inventory (PTGI). Participants were randomly assigned to one of three groups: the control group, a web-only group, or a health coaching + web group. The primary endpoint was based on a composite of PA, weight, and PTGI score at 12 months.

RESULTS

Patients in the health coaching + web group (difference = 6.6%, P = .010) and the web-only group (difference = 5.9%, P = .031) had greater overall improvements across the three-outcome composite than the control group. The health coaching + web group had greater overall improvement in PTGI (difference = 12.6%; P < .001) than the control group, but not in PA and weight.

CONCLUSION

The web-based program, with or without health coaching, may improve health behaviours including PA, weight, and distress management among cancer survivors within 2 months of completing primary cancer treatment. The web-based program with health coaching was mainly effective for reducing psychological distress.

BRCA1/BRCA2 Pathogenic Variant Breast Cancer: Treatment and Prevention Strategies

Hereditary breast cancer is known for its strong tendency of inheritance. Most hereditary breast cancers are related to BRCA1/BRCA2 pathogenic variants. The lifelong risk of breast cancer in pathogenic BRCA1 and BRCA2 variant carriers is approximately 65% and 45%, respectively, whereas that of ovarian cancer is estimated to be 39% and 11%, respectively. Therefore, understanding these variants and clinical knowledge on their occurrence in breast cancers and carriers are important. BRCA1 pathogenic variant breast cancer shows more aggressive clinicopathological features than the BRCA2 pathogenic variant breast cancer. Compared with sporadic breast cancer, their prognosis is still debated. Treatments of BRCA1/BRCA2 pathogenic variant breast cancer are similar to those for BRCA-negative breast cancer, mainly including surgery, radiotherapy, and chemotherapy. Recently, various clinical trials have investigated poly (adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitor treatment for advanced-stage BRCA1/BRCA2 pathogenic variant breast cancer. Among the various PARP inhibitors, olaparib and talazoparib, which reached phase III clinical trials, showed improvement of median progression-free survival around three months. Preventive and surveillance strategies for BRCA pathogenic variant breast cancer to reduce cancer recurrence and improve treatment outcomes have recently received increasing attention. In this review, we provide an information on the clinical features of BRCA1/BRCA2 pathogenic variant breast cancer and clinical recommendations for BRCA pathogenic variant carriers, with a focus on treatment and prevention strategies. With this knowledge, clinicians could manage the BRCA1/BRCA2 pathogenic variant breast cancer patients more effectively.

Dystrophic Calcifications in the Breast from Secondary Hyperparathyroidism

Background

Soft tissue calcification is common in patients with secondary hyperparathyroidism who have received long-term treatment with hemodialysis. However, calcifications in the breast parenchyma are not common. We report a case of a woman with dystrophic breast calcifications from secondary hyperparathyroidism.

Case Report

A 65-year-old woman presented with a palpable mass in her right breast which she had discovered 1 month ago. She had a medical history of end-stage renal disease. Mammography and ultrasound revealed large dystrophic calcifications in both breasts. Core needle biopsy was performed for calcifications in the right breast, and the pathologic diagnosis was dystrophic calcification in the stroma from secondary hyperparathyroidism.

Conclusion

Reviewing our case will contribute to a fast and correct diagnosis in patients with dystrophic breast calcifications and lab results indicating secondary hyperparathyroidism, and will help discriminate these benign lesions from malignancies.

Assessment of Quality of Life and Safety in Postmenopausal Breast Cancer Patients Receiving Letrozole as an Early Adjuvant Treatment

Purpose

There are few reports from Asian countries about the long-term results of aromatase inhibitor adjuvant treatment for breast cancer. This observational study aimed to evaluate the long-term effects of letrozole in postmenopausal Korean women with operable breast cancer.

Methods

Self-reported quality of life (QoL) scores were serially assessed for 3 years during adjuvant letrozole treatment using the Korean version of the Functional Assessment of Cancer Therapy-Breast questionnaires (version 3). Changes in bone mineral density (BMD) and serum cholesterol levels were also examined.

Results

All 897 patients received the documented informed consent form and completed a baseline questionnaire before treatment. Adjuvant chemotherapy was administered to 684 (76.3%) subjects, and 410 (45.7%) and 396 (44.1%) patients had stage I and II breast cancer, respectively. Each patient completed questionnaires at 3, 6, 12, 18, 24, 30, and 36 months after enrollment. Of 897 patients, 749 (83.5%) completed the study. The dropout rate was 16.5%. The serial trial outcome index, the sum of the physical and functional well-being subscales, increased gradually and significantly from baseline during letrozole treatment (p<0.001). The mean serum cholesterol level increased significantly from 199 to 205 after 36 months (p=0.042). The mean BMD significantly decreased from −0.39 at baseline to −0.87 after 36 months (p<0.001).

Conclusion

QoL gradually improved during letrozole treatment. BMD and serum cholesterol level changes were similar to those in Western countries, indicating that adjuvant letrozole treatment is well tolerated in Korean women, with minimal ethnic variation.

Cytokeratin 18 is necessary for initiation of TGF-β1-induced epithelial-mesenchymal transition in breast epithelial cells

During epithelial-mesenchymal transition (EMT), epithelial cells lose key phenotypic markers (e.g., E-cadherin and cytokeratin 18) and acquire mesenchymal markers (e.g., N-cadherin and vimentin). Although the loss of cytokeratin 18 is a hallmark of EMT, the regulatory role of cytokeratin 18 in EMT is not yet fully understood. Here, we report that cytokeratin 18 is involved in the regulation of transforming growth factor-beta1 (TGF-β1)-induced EMT in breast epithelial cells. When MCF10A cells were treated with TGF-β1 for 24 h, considerable morphological changes, indicative of the early stages of EMT (e.g., loss of cell-cell contact), were observed and cytokeratin 18 was downregulated. However, E-cadherin levels were not altered until a later time point. This suggests that cytokeratin 18 may play an active role during the earlier stages of EMT. Consistent with this notion, siRNA-mediated knockdown of cytokeratin 18 delayed TGF-β1-mediated EMT, and the associated downregulation of E-cadherin reduced the phosphorylation/nuclear localization of smad 2/3 and decreased the expression levels of snail and slug (which inhibit E-cadherin expression in epithelial cells as an early response to TGF-β1). Taken together, these results suggest that cytokeratin 18 critically contributes to initiating TGF-β1-induced EMT via the smad 2/3-mediated regulation of snail and slug expression in breast epithelial cells.

A comparison of the clinical outcomes of patients with invasive lobular carcinoma and invasive ductal carcinoma of the breast according to molecular subtype in a Korean population

Background

To investigate the clinicopathological characteristics and the survival outcomes of invasive lobular carcinoma (ILC) patients compared to invasive ductal carcinoma (IDC) patients according to their molecular subtype.

Methods

We compared the clinicopathological characteristics, breast cancer-specific survival (BCSS) and overall survival (OS) between patients with IDC (n = 14,547) and ILC (n = 528).

Results

The ILC presented with a larger tumor size, more advanced cancer stage, increased rate of hormonal receptor positivity, human epidermal growth factor 2 (HER2) negativity and mastectomy than the IDC. The ILC patients more frequently presented with the luminal A subtype, whereas the IDC patients more frequently presented with the luminal B, HER2-overexpression, or triple negative subtype. The BCSS and OS were not significantly different between the IDC and ILC for each molecular subtype.

Conclusions

Similar to IDC patients, molecular subtype should be considered when determining the prognosis and treatment regimen for ILC patients.

Long-term results of forward intensity-modulated radiation therapy for patients with early-stage breast cancer

Purpose

To observe long-term clinical outcomes for patients with early-stage breast cancer treated with forward intensity-modulated radiation therapy (IMRT), including local control and clinical toxicities.

Materials and Methods

We retrospectively analyzed a total of 214 patients with stage I-II breast cancer who were treated with breast conserving surgery followed by adjuvant breast radiation therapy between 2001 and 2008. All patients were treated using forward IMRT. The whole breast was irradiated to a dose of 50 to 50.4 Gy followed by an 8 to 12 Gy electron boost to the surgical bed.

Results

The median age was 46 years (range, 21 to 82 years) and the medial follow-up time was 7.3 years (range, 2.4 to 11.7 years). Stage T1 was 139 (65%) and T2 was 75 (35%), respectively. Ipsilateral breast recurrence was observed in 3 patients. The 5- and 10-year local control rates were 99.1% and 97.8%, respectively. The cosmetic outcome was evaluated according to the Harvard scale and 89.4% of patients were scored as excellent or good.

Conclusion

The whole breast radiation therapy as an adjuvant treatment using a forward IMRT technique showed excellent long-term local control as well as favorable outcomes of toxicity and cosmesis.

Leptin as a potential target for estrogen receptor-positive breast cancer

Purpose

Leptin is a potent adipokine that plays a significant role in tumor development and the progression of breast cancer. The aim of this study was to evaluate whether leptin affects the response to tamoxifen treatment in estrogen receptor (ER)-positive breast cancer cells.

Methods

Leptin, leptin receptor (Ob-R), and activation of signaling pathways were studied by Western immunoblotting. The effects of leptin on tamoxifen-dependent growth inhibition were studied in MCF-7 and T-47D cells.

Results

Leptin was expressed in MCF-7 and T-47D and had a proliferative effect on MCF-7 cells. Leptin significantly inhibited the antiestrogenic effect of tamoxifen in both cells only under β-estradiol (E2) (20 nM) conditions. In MCF-7, the inhibitory effect against tamoxifen was a result from the activation of the ERK1/2 and STAT3 signal transduction pathway.

Conclusion

Leptin interferes with the effects of tamoxifen under E2 stimulated conditions in ER-positive breast cancer cells. These results imply that inhibition of leptin is expected to enhance the response to tamoxifen in ER-positive breast cancer cells, and, therefore, could be a promising way to overcome endocrine resistance.

Metastasis to the breast from colonic adenocarcinoma

A 63-year-old woman was referred to a breast surgeon with a breast mass discovered incidentally during follow-up study after colon cancer surgery. Invasive adenocarcinoma was revealed on core needle biopsy. Wide excision of the breast including the tumor was performed. On standard histological examination the tumor showed features of moderately differentiated adenocarcinoma. The immunohistochemistry study revealed positive results for cytokeratin (CK)20 and CDX2, but negative for CK7. These are typical characteristics for colon cancer. Considering her history of subtotal colectomy for sigmoid colon cancer, it is presumable that the mass in the breast was of colonic origin, and it was an extremely rare case of metastasis to the breast from primary colorectal neoplasm. Although the instance is rare, clinicians should keep the possibility of breast metastasis from colorectal cancer in mind for early and correct diagnosis.

Secretory carcinoma of the breast

Secretory carcinoma of the breast is a rare but histologically distinct variant of invasive ductal carcinoma that has an indolent growth pattern and a more favorable prognosis than that of typical ductal carcinoma. We present the imaging and histopathologic findings of a case of this tumor that initially manifested as a palpable mass in the left breast of a 31-year-old woman. It appeared sonographically as a round, well-circumscribed but microlobulated hypoechoic solid mass. Secretory carcinoma of the breast may resemble other well-circumscribed breast carcinomas as well as some benign masses, including fibroadenomas. Breast imagers should be aware of this rare tumor's nonspecific imaging features and clinical implications when making a differential diagnosis of solid breast masses.