Ivo A. Olivotto

Adjuvant radiotherapy and chemotherapy in node-positive premenopausal women with breast cancer

BACKGROUND Radiotherapy after mastectomy to treat early breast cancer has been known since the 1940s to reduce rates of local relapse. However, the routine use of postoperative radiotherapy began to decline in the 1980s because it failed to improve overall survival. We prospectively tested the efficacy of combining radiotherapy with chemotherapy. METHODS From 1978 through 1986, 318 premenopausal women with node-positive breast cancer were randomly assigned, after modified radical mastectomy, to receive chemotherapy plus radiotherapy or chemotherapy alone. Radiotherapy was given to the chest wall and locoregional lymph nodes between the fourth and fifth cycles of cyclophosphamide, methotrexate, and fluorouracil. RESULTS After 15 years of follow-up, the women assigned to chemotherapy plus radiotherapy had a 33 percent reduction in the rate of recurrence (relative risk, 0.67; 95 percent confidence interval, 0.50 to 0.90) and a 29 percent reduction in mortality from breast cancer (relative risk, 0.71; 95 percent confidence interval, 0.51 to 0.99), as compared with the women treated with chemotherapy alone. CONCLUSIONS Radiotherapy combined with chemotherapy after modified radical mastectomy decreases rates of locoregional and systemic relapse and reduces mortality from breast cancer.

Contralateral breast cancer in BRCA1 and BRCA2 mutation carriers.

PURPOSE To estimate the risk of contralateral breast cancer in BRCA1 and BRCA2 carriers after diagnosis and to determine which factors are predictive of the risk of a second primary breast cancer. PATIENTS AND METHODS Patients included 491 women with stage I or stage II breast cancer, for whom a BRCA1 or BRCA2 mutation had been identified in the family. Patients were followed from the initial diagnosis of cancer until contralateral mastectomy, contralateral breast cancer, death, or last follow-up. RESULTS The actuarial risk of contralateral breast cancer was 29.5% at 10 years. Factors that were predictive of a reduced risk were the presence of a BRCA2 mutation (v BRCA1 mutation; hazard ratio [HR], 0.73; 95% CI, 0.47 to 1.15); age 50 years or older at first diagnosis (v <or= 49 years; HR, 0.63; 95% CI, 0.36 to 1.10); use of tamoxifen (HR, 0.59; 95% CI, 0.35 to 1.01); and history of oophorectomy (HR, 0.44; 95% CI, 0.21 to 0.91). The effect of oophorectomy was particularly strong in women first diagnosed prior to age 49 years (HR, 0.24; 95% CI, 0.07 to 0.77). For women who did not have an oophorectomy or take tamoxifen, the 10-year risk of contralateral cancer was 43.4% for BRCA1 carriers and 34.6% for BRCA2 carriers. CONCLUSION The risk of contralateral breast cancer in women with a BRCA mutation is approximately 40% at 10 years, and is reduced in women who take tamoxifen or who undergo an oophorectomy.

A Multicenter Randomized Trial of Breast Intensity-Modulated Radiation Therapy to Reduce Acute Radiation Dermatitis

PURPOSE Dermatitis is a frequent adverse effect of adjuvant breast radiotherapy. It is more likely in full-breasted women and when the radiation is distributed nonhomogeneously in the breast. Breast intensity-modulated radiation therapy (IMRT) is a technique that ensures a more homogeneous dose distribution. PATIENTS AND METHODS A multicenter, double-blind, randomized clinical trial was performed to test if breast IMRT would reduce the rate of acute skin reaction (notably moist desquamation), decrease pain, and improve quality of life compared with standard radiotherapy using wedges. Patients were assessed each week during and up to 6 weeks after radiotherapy. RESULTS A total of 358 patients were randomly assigned between July 2003 and March 2005 in two Canadian centers, and 331 were included in the analysis. Breast IMRT significantly improved the dose distribution compared with standard radiation. This translated into a lower proportion of patients experiencing moist desquamation during or up to 6 weeks after their radiation treatment; 31.2% with IMRT compared with 47.8% with standard treatment (P = .002). A multivariate analysis found the use of breast IMRT (P = .003) and smaller breast size (P < .001) were significantly associated with a decreased risk of moist desquamation. The use of IMRT did not correlate with pain and quality of life, but the presence of moist desquamation did significantly correlate with pain (P = .002) and a reduced quality of life (P = .003). CONCLUSION Breast IMRT significantly reduced the occurrence of moist desquamation compared with a standard wedged technique. Moist desquamation was correlated with increased pain and reduction in the quality of life.

Population-Based Validation of the Prognostic Model ADJUVANT! for Early Breast Cancer

PURPOSE Adjuvant! (www.adjuvantonline.com) is a web-based tool that predicts 10-year breast cancer outcomes with and without adjuvant systemic therapy, but it has not been independently validated. METHODS Using the British Columbia Breast Cancer Outcomes Unit (BCOU) database, demographic, pathologic, staging, and treatment data on 4,083 women diagnosed between 1989 and 1993 in British Columbia with T1-2, N0-1, M0 breast cancer were abstracted and entered into Adjuvant! to calculate predicted 10-year overall survival (OS), breast cancer-specific survival (BCSS), and event-free survival (EFS) for each patient. Individual BCOU observed outcomes at 10 years were independently determined. Predicted and observed outcomes were compared. RESULTS Across all 4,083 patients, 10-year predicted and observed outcomes were within 1% for OS, BCSS, and EFS (all P > .05). Predicted and observed outcomes were within 2% for most demographic, pathologic, and treatment-defined subgroups. Adjuvant! overestimated OS, BCSS, and EFS in women younger than age 35 years (predicted-observed = 8.6%, 9.6%, and 13.6%, respectively; all P < .001) or with lymphatic or vascular invasion (LVI; predicted-observed = 3.6%, 3.8%, and 4.2%, respectively; all P < .05); these two prognostic factors were not automatically incorporated within the Adjuvant! algorithm. After adjusting for the distribution of LVI, using the prognostic factor impact calculator in Adjuvant!, 10-year predicted and observed outcomes were no longer significantly different. CONCLUSION Adjuvant! performed reliably. Patients younger than age 35 or with known additional adverse prognostic factors such as LVI require adjustment of risks to derive reliable predictions of prognosis without adjuvant systemic therapy and the absolute benefits of adjuvant systemic therapy.

The Impact of New Chemotherapeutic and Hormone Agents on Survival in a Population-based Cohort of Women with Metastatic Breast Cancer

Over the past decade, a number of new therapeutic agents have become available in the treatment of metastatic breast cancer (MBC). This study characterized the use and assessed the impact on survival of population‐based access to new agents for the treatment of MBC.

Chronic Arm Morbidity After Curative Breast Cancer Treatment: Prevalence and Impact on Quality of Life

PURPOSE To determine the prevalence of and contributing factors for chronic arm morbidity including lymphedema in breast cancer patients after treatment and to assess the impact of arm morbidity on quality of life (QOL). PATIENTS AND METHODS A four-question screening questionnaire was developed and mailed to a random sample of 744 breast cancer patients treated curatively in two cancer centers from 1993 to 1997. Patients were without recurrence and at least 2 years from diagnosis. Respondents were classified as with or without arm-related symptoms on the basis of the survey. Stratified random samples from each group were then invited for a detailed assessment of their symptoms and signs, including the presence of lymphedema. Their QOL was assessed by the European Organization for Research and Treatment of Cancer QOL Questionnaire C-30 and by a detailed arm problem questionnaire that assessed various aspects of daily arm functioning. RESULTS Approximately half of all screened patients were symptomatic and 12.5% of all assessed patients had lymphedema. Axillary dissection (AD) and axillary radiotherapy (RT) after dissection were statistically significantly related to the occurrence of arm symptoms (odds ratio for AD = 3.3, P <.001; odds ratio for RT = 3.1, P <.001). Symptomatic patients and patients with lymphedema both had impaired QOL compared with asymptomatic patients. CONCLUSION Treatment for breast cancer is associated with considerable arm morbidity, which has a negative impact on QOL. Arm morbidity should be carefully monitored in future studies involving local treatment modalities for breast cancer.

Ten-Year Multi-Institutional Results of Breast-Conserving Surgery and Radiotherapy in BRCA1/2-Associated Stage I/II Breast Cancer

PURPOSE We compared the outcome of breast-conserving surgery and radiotherapy in BRCA1/2 mutation carriers with breast cancer versus that of matched sporadic controls. METHODS A total of 160 BRCA1/2 mutation carriers with breast cancer were matched with 445 controls with sporadic breast cancer. Primary end points were rates of in-breast tumor recurrence (IBTR) and contralateral breast cancers (CBCs). Median follow-up was 7.9 years for mutation carriers and 6.7 years for controls. RESULTS There was no significant difference in IBTR overall between carriers and controls; 10- and 15-year estimates were 12% and 24% for carriers and 9% and 17% for controls, respectively (hazard ratio [HR], 1.37; P = .19). Multivariate analyses for IBTR found BRCA1/2 mutation status to be an independent predictor of IBTR when carriers who had undergone oophorectomy were removed from analysis (HR, 1.99; P = .04); the incidence of IBTR in carriers who had undergone oophorectomy was not significantly different from that in sporadic controls (P = .37). CBCs were significantly greater in carriers versus controls, with 10- and 15-year estimates of 26% and 39% for carriers and 3% and 7% for controls, respectively (HR, 10.43; P < .0001). Tamoxifen use significantly reduced risk of CBCs in mutation carriers (HR, 0.31; P = .05). CONCLUSION IBTR risk at 10 years is similar in BRCA1/2 carriers treated with breast conservation surgery who undergo oophorectomy versus sporadic controls. As expected, CBCs are significantly increased in carriers. Although the incidence of CBCs was significantly reduced in mutation carriers who received tamoxifen, this rate remained significantly greater than in controls. Additional strategies are needed to reduce contralateral cancers in these high-risk women.

Estrogen Receptor Status in BRCA1- and BRCA2-Related Breast Cancer: The Influence of Age, Grade, and Histological Type

Purpose: BRCA1-related breast cancers are more frequently estrogen receptor (ER) negative than are either BRCA2-related or nonhereditary breast cancers. The relationship between ER status and other clinical features of hereditary breast cancers has not been well studied. Experimental Design: ER status, grade, and histological tumor type were evaluated in 1131 women with invasive breast cancer, ascertained at 10 centers in North America. There were 208 BRCA1 mutation carriers, 88 BRCA2 carriers, and 804 women without a known mutation. We stratified the patients by mutation status, grade, age, and histological type and calculated the percentage of ER-positive tumors within each stratum. Results: BRCA1 mutation carriers were more likely to have ER-negative breast cancers than were women in other groups, after adjustment for age, grade, and histological subtype (P < 0.001). Only 3.9% of BRCA1-related breast cancers were ER-positive cancers occurring in women in their postmenopausal years. The direction and magnitude of the change in ER status with increasing age at diagnosis in BRCA1 carriers was significantly different from in BRCA2 carriers (Pintercept = 0.0002, Pslope = 0.04). Notably, changes in ER status with age at diagnosis for BRCA1 carriers and noncarriers were almost identical (Pslope = 0.98). Conclusions: The strong relationship between the presence of a BRCA1 mutation and the ER-negative status of the breast cancers is neither a consequence of the young age at onset nor the high grade but is an intrinsic property of BRCA1-related cancers. The ER-negative status of these cancers may reflect the cell of origin of BRCA1-related cancers.

Impact on Survival of Time From Definitive Surgery to Initiation of Adjuvant Chemotherapy for Early-Stage Breast Cancer

PURPOSE To determine if time to start of adjuvant chemotherapy after curative surgery influences survival in early-stage breast cancer. PATIENTS AND METHODS A retrospective review was conducted of 2,594 patients receiving adjuvant chemotherapy for stage I and II breast cancer between 1989 and 1998 at the British Columbia Cancer Agency. Relapse-free survival (RFS) and overall survival (OS) were compared among patients grouped by time from definitive curative surgery to start of adjuvant chemotherapy (< or = 4 weeks, > 4 to 8 weeks, > 8 to 12 weeks, and >12 to 24 weeks). RESULTS RFS and OS were similar for women starting chemotherapy up to 12 weeks after surgery. OS hazard ratio (univariate) for initiation of chemotherapy more than 12 weeks compared with 12 weeks or less after surgery was 1.5 (95% CI, 1.07 to 2.10; P = .017). Five-year OS rates were 84%, 85%, 89%, and 78%, (log-rank P = .013); RFS rates were 74%, 79%, 82%, and 69% (log-rank P = .004) for patients starting chemotherapy 4 weeks or fewer, more than 4 to 8 weeks, more than 8 to 12 weeks, and more than 12 to 24 weeks after surgery, respectively. In multivariate analysis, independent prognostic factors were grade, size, nodal status, estrogen receptor, age, and lymphatic and/or vascular invasion. Initiation of adjuvant chemotherapy more than 12 weeks from surgery remained significantly associated with inferior survival, with a hazard ratio of 1.6 (95% CI, 1.2 to 2.3; P = .005). CONCLUSION This retrospective analysis suggests that adjuvant chemotherapy is equally effective up to 12 weeks after definitive surgery but that RFS and OS appear to be compromised by delays of more than 12 weeks after definitive surgery.

Human Epidermal Growth Factor Receptor 2 Overexpression As a Prognostic Factor in a Large Tissue Microarray Series of Node-Negative Breast Cancers

PURPOSE Human epidermal growth factor receptor 2 gene (HER2) is associated with a poorer outcome in node-positive breast cancer, but the results are conflicting in node-negative disease. This study assessed the prognostic impact of HER2 overexpression/amplification in a large series of node-negative breast cancers. PATIENTS AND METHODS A tissue microarray (TMA) series was constructed consisting of 4,444 invasive breast cancers diagnosed in British Columbia from 1986 to 1992. Within this series, 2,026 patients were node negative, of whom 70% did not receive adjuvant systemic therapy. The TMA series was assessed for estrogen receptor (ER) and HER2. Logistic regression modeling was used to estimate odds ratios at the 10-year follow-up. RESULTS HER2 was positive in 10.2% of the node-negative cohort. In this cohort, an inferior outcome was seen in patients with HER2-positive tumors compared with HER2-negative tumors for 10-year relapse-free survival (RFS; 65.9% v 75.5%, respectively; P = .01), distant RFS (71.2% v 81.8%, respectively; P = .004), and breast cancer-specific survival (BCSS; 75.5% v 86.3%, respectively; P = .001). A trend for a worse overall survival was also seen (P = .06). HER2 was an independent poor prognostic factor for RFS and BCSS at 10 years, with odds ratios of 1.71 (P = .01) and 2.03 (P = .003), respectively. The number of HER2-positive tumors that were <or= 1 cm was small, but there was a trend for a worse outcome in T1b tumors. CONCLUSION HER2 overexpression/amplification is correlated with a poorer outcome in node-negative breast cancer. Larger studies are needed to more clearly define the prognostic impact of HER2 in tumors <or= 1 cm, particularly within the separate hormone receptor subgroups.