Jane McLennan

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.

Risk-Reducing Salpingo-Oophorectomy in BRCA Mutation Carriers: Role of Serial Sectioning in the Detection of Occult Malignancy

PURPOSE Women who carry deleterious mutations of BRCA1 or BRCA2 genes have up to a 54% lifetime risk of developing ovarian cancer. After childbearing, women at high risk increasingly choose bilateral risk-reducing salpingo-oophorectomy (RRSO). Two recent studies of BRCA mutation carriers reported occult malignancy in 2.5% of women undergoing RRSO. This study aimed to increase this detection rate using a protocol. METHODS In 1996, the University of California San Francisco Gynecologic Oncology Program instituted a surgical-pathologic RRSO protocol that was composed of complete removal and serial sectioning of both ovaries and fallopian tubes, peritoneal and omental biopsies, and collection of peritoneal washings for cytology. We report the pathologic findings in 67 BRCA mutation carriers according to the degree of adherence to this protocol. RESULTS Of the 67 procedures, the protocol was followed completely or partially in 41 (61%). Seven occult malignancies were discovered, four in the fallopian tube and three in the ovaries. Six of these were microscopic, and all seven (17%) were found in specimens from complete or partial protocol procedures as opposed to standard procedures (P = .026). Other variables such as age, parity, BRCA1 or BRCA2 mutation, or type of surgery did not alter the strong effect of protocol procedure on the cancer detection rate. CONCLUSION A rigorous operative and pathologic protocol for RRSO increases the detection rate of occult ovarian malignancy in BRCA mutation carriers nearly seven-fold. If confirmed, this finding will alter postoperative management because additional staging, chemotherapy, and follow-up may be necessary in affected women.

Breast tumor copy number aberration phenotypes and genomic instability

BackgroundGenomic DNA copy number aberrations are frequent in solid tumors, although the underlying causes of chromosomal instability in tumors remain obscure. Genes likely to have genomic instability phenotypes when mutated (e.g. those involved in mitosis, replication, repair, and telomeres) are rarely mutated in chromosomally unstable sporadic tumors, even though such mutations are associated with some heritable cancer prone syndromes.MethodsWe applied array comparative genomic hybridization (CGH) to the analysis of breast tumors. The variation in the levels of genomic instability amongst tumors prompted us to investigate whether alterations in processes/genes involved in maintenance and/or manipulation of the genome were associated with particular types of genomic instability.ResultsWe discriminated three breast tumor subtypes based on genomic DNA copy number alterations. The subtypes varied with respect to level of genomic instability. We find that shorter telomeres and altered telomere related gene expression are associated with amplification, implicating telomere attrition as a promoter of this type of aberration in breast cancer. On the other hand, the numbers of chromosomal alterations, particularly low level changes, are associated with altered expression of genes in other functional classes (mitosis, cell cycle, DNA replication and repair). Further, although loss of function instability phenotypes have been demonstrated for many of the genes in model systems, we observed enhanced expression of most genes in tumors, indicating that over expression, rather than deficiency underlies instability.ConclusionMany of the genes associated with higher frequency of copy number aberrations are direct targets of E2F, supporting the hypothesis that deregulation of the Rb pathway is a major contributor to chromosomal instability in breast tumors. These observations are consistent with failure to find mutations in sporadic tumors in genes that have roles in maintenance or manipulation of the genome.

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.

Predictors of contralateral breast cancer in BRCA1 and BRCA2 mutation carriers.

Purpose:The objective of this study was to estimate the risk of contralateral breast cancer in BRCA1 and BRCA2 carriers; and measure the extent to which host, family history, and cancer treatment-related factors modify the risk.Patients and methods:Patients were 810 women, with stage I or 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:Overall, 149 subjects (18.4%) developed a contralateral breast cancer. The 15-year actuarial risk of contralateral breast cancer was 36.1% for women with a BRCA1 mutation and was 28.5% for women with a BRCA2 mutation. Women younger than 50 years of age at the time of breast cancer diagnosis were significantly more likely to develop a contralateral breast cancer at 15 years, compared with those older than 50 years (37.6 vs 16.8%; P=0.003). Women aged <50 years with two or more first-degree relatives with early-onset breast cancer were at high risk of contralateral breast cancer, compared with women with fewer, or no first-degree relatives with breast cancer (50 vs 36%; P=0.005). The risk of contralateral breast cancer was reduced with oophorectomy (RR 0.47; 95% CI 0.30–0.76; P=0.002).Conclusion:The risk of contralateral breast cancer risk in BRCA mutation carriers declines with the age of diagnosis and increases with the number of first-degree relatives affected with breast cancer. Oophorectomy reduces the risk of contralateral breast cancer in young women with a BRCA mutation.

Disruption of the expected positive correlation between breast tumor size and lymph node status in BRCA1‐related breast carcinoma

A positive correlation between breast tumor size and the number of axillary lymph nodes containing tumor is well established. It has been reported that patients with BRCA1‐related breast carcinoma are more likely than patients with nonhereditary breast carcinoma to have negative lymph node status. Therefore, the authors questioned whether the known positive correlation between tumor size and lymph node status also was present in women with BRCA1‐related breast carcinomas.

Risk-reducing salpingo-oophorectomy (RRSO) in BRCA mutation carriers: experience with a consecutive series of 111 patients using a standardized surgical-pathological protocol.

Background: Women carriers of BRCA mutations often have occult malignancy found at the time of risk-reducing bilateral salpingo-oophorectomy (RRSO). We report outcomes in 111 consecutive BRCA-positive women who had RRSO using a rigorous surgical-pathological protocol from 1996 to 2008. Method: We identified risk factors associated with finding an occult malignancy at RRSO with outcomes followed for a median of 61 months. Results: A total of 111 BRCA carriers elected RRSO, 10 patients [9.1%] had 14 sites of occult neoplasia. Two patients had invasive serous fallopian tube carcinoma (TSC) only, 1 patient had invasive serous ovarian carcinoma (OSC) only, 5 patients had tubal intraepithelial carcinoma (TIC) only, and 2 patients had multifocal lesions of the ovary (OSC) and TIC. Occult ovarian carcinomas were only detected in BRCA1 patients, and all BRCA2 carcinomas involved only the fallopian tube. The odds of finding occult carcinoma is 4 times greater (odds ratio, 4.3; 95% confidence interval, 1.06-20.7) in women older than 50 than in younger ones (P = 0.023). A history of invasive breast cancer was associated with a reduced risk of occult carcinoma (odds ratio, 0.2; 95% confidence interval, 0.05-0.85). In median follow-up of 5 years, recurrence rate after detection of an occult carcinoma was 10% and the risk for primary peritoneal carcinoma was less than 1%. Conclusion: A rigorous surgical protocol with meticulous pathologic review at RRSO yielded an overall detection rate of 9.1% for occult gynecological carcinoma in BRCA mutation carriers followed by a multidisciplinary team at a single institution. Primary peritoneal carcinoma after RRSO is rare.

Ductal Carcinoma In Situ in BRCA Mutation Carriers

PURPOSE The current literature suggests that ductal carcinoma in situ (DCIS) of the breast is infrequently diagnosed in patients with BRCA germline mutations. We studied women at high risk of hereditary breast cancer syndromes who underwent testing for BRCA1 and BRCA2 to estimate DCIS prevalence and incidence in known BRCA-positive women compared with high-risk women who were mutation negative. METHODS We analyzed breast event outcomes in a retrospective cohort of 129 BRCA-positive and 269 BRCA-negative women undergoing genetic testing for a BRCA mutation between September 1996 and December 2003 at University of California, San Francisco. We estimated the frequency of DCIS and invasive cancer and time to breast events from birth using a Cox proportional hazard model for competing risks. Histologic grade of DCIS was also compared between groups. RESULTS Among BRCA carriers, 48 (37%) had DCIS (with or without invasive cancer) compared with 92 noncarriers (34%). Univariate analysis showed that both DCIS and invasive cancer had an earlier onset in mutation carriers than in noncarriers, although on a per-woman basis, this difference was not statistically significant. High-grade DCIS was more common in BRCA1 mutation carriers than in patients without a mutation (P = .02). CONCLUSION DCIS is equally as prevalent in patients who carry deleterious BRCA mutations as in high familial-risk women who are noncarriers, but occurs at an earlier age. Our results argue for the consideration of DCIS as a criterion for BRCA risk assessments with appropriate weighting in prediction models such as BRCAPRO.

Long term follow up of BRCA1 and BRCA2 mutation carriers with unsuspected neoplasia identified at risk reducing salpingo-oophorectomy.

OBJECTIVES The reported incidence of neoplasia identified at the time of risk-reducing salpingo-oophorectomy (RRSO) in germline BRCA1/2 mutation carriers ranges from 4 to 12% but long-term outcomes have not been described. We evaluated recurrence and survival outcomes of mutation carriers with neoplastic lesions identified at RRSO. METHODS We identified BRCA1/2 mutation carriers with neoplasia at RRSO at three institutions. Data was collected on clinical variables, adjuvant treatment and follow-up. RESULTS We identified 32 mutation carriers with invasive carcinomas (n=15) or high-grade intraepithelial neoplasia (n=17) that were not suspected prior to surgery. 26 occurred in BRCA1 and 6 in BRCA2 mutation carriers. Median and mean age for carcinomas were 50 years and 49.3 respectively, significantly younger than for intraepithelial neoplasm, median 53 years, and mean 55 years (p=0.04). For the 15 invasive carcinomas, median follow up was 88 months (range 45-172 months), 7 recurred (47%), median time to recurrence was 32.5 months and 3 have died of disease; 1 additional patient died of breast cancer. Overall survival was 73%, disease specific overall survival was 80% and disease free survival was 66%. For the 17 high-grade intraepithelial neoplasms, median follow up was 80 months (range 40-150), 4 were treated with chemotherapy. One recurred at 43 months and is currently not on therapy with a normal CA125, 16 months later. All patients with noninvasive neoplasia are alive. CONCLUSIONS BRCA1 and BRCA2 mutation carriers with unsuspected invasive carcinoma at RRSO have a relatively high rate of recurrence despite predominantly early stage, small volume disease. High-grade intraepithelial neoplasms rarely recur as carcinoma and may not require adjuvant chemotherapy.

A Comparison of Bilateral Breast Cancers in BRCA Carriers

Background: Women with breast cancer and a BRCA mutation have a high risk of developing a contralateral breast cancer. It is generally believed that the two cancers represent independent events. However, the extent of concordance between the first and second tumors with respect to hormone receptor expression and other pathologic features is unknown. Purpose: To determine the degree of concordance of estrogen receptor (ER) status, tumor grade, and histology in tumors from women with bilateral breast cancer and a BRCA mutation. Subjects and Methods: Women with a history of bilateral invasive breast cancers were selected from an international registry of women with BRCA1 or BRCA2 mutations. Medical records were reviewed to document the characteristics of each cancer and the treatments received. Results: Data were available for 286 women with bilateral breast cancer and a BRCA mutation (211 BRCA1; 75 BRCA2). The mean interval between first and second tumor was 5.1 years. The two tumors were concordant more often than expected for ER status (P < 0.0001) and for grade (P < 0.0001), but not for histology (P = 0.55). The ER status of the first tumor was highly predictive of the ER status of the second tumor (odds ratio, 8.7; 95% confidence interval, 3.5-21.5; P < 0.0001). Neither age, menopausal status, oophorectomy nor tamoxifen use was predictive of the ER status of the second tumor. Conclusions: There is strong concordance in ER status and tumor grade between independent primary breast tumors in women with a BRCA mutation. The excess concordance may be due to common risk factors, genetic variation, or the existence of a preneoplastic lesion that is common to both tumors.