Immunohistochemical detection of a germline BRCA1 mutation in a breast and ovarian cancer family

Tumours from four individuals in a breast and ovarian cancer family with a known deleterious germline BRCA1 mutation, were analyzed using BRCA1 antibodies. In addition, we examined tumours from 96 female patients with early-onset breast cancer, who were not selected because of any family history. Paraffin-embedded tumour sections were examined by standard immunohistochemical analysis. Three familial tumours from BRCA1 carriers displayed focal negativity. This observation was not seen in a non-mutation carrier from the same family. It was found that 9/96 (9%) early-onset breast tumours had total BRCA1 negativity. In addition, 2/2 (100%) medullary breast carcinomas displayed negativity for both antibodies. Our results indicate that BRCA1 antibodies can discriminate between familial tumours with and without a deleterious mutation from one family. Further mutation studies in early-onset breast cancer group will be necessary to evaluate the use of immunohistochemistry as a rapid, initial screening technique to identify BRCA1 mutations.     

The prevalence of germline BRCA1 and BRCA2 mutations in young women with breast cancer undergoing breast-conservation therapy

BACKGROUND: Germline mutations of BRCA1 and BRCA2 increase the risk for breast cancer. Mutation carriers selecting breast-conservation therapy (BCT) for treatment of operable breast cancer experience a higher rate of new primary breast cancers. We sought to determine the frequency of BRCA1/BRCA2 mutations in women who underwent BCT. Genetic testing results were compared with the prior probability of mutations in either gene. METHODS: Eighty-nine patients age 39 or younger entered the study. Genetic testing was performed for BRCA1 and BRCA2 and the BRCAPRO model determined the probability of carrying a mutation. RESULTS: Eight mutations were discovered (prevalence, 9.0%). Twenty (22%) uncharacterized sequence variants were found. The prior probability of carrying a mutation was 14%. Mutation carriers had a higher prior probability (.49) compared with women with uncharacterized variants (.09) or with normal genes (.11). CONCLUSIONS: BRCA1 and BRCA2 mutations are common (9%) among unselected young breast cancer patients undergoing BCT.     

Cancer risks for Australian women with a BRCA1 or a BRCA2 mutation

One of the primary purposes of genetic testing for mutations in the BRCA1 and BRCA2 genes in patients with familial breast/ovarian cancer has been to provide accurate advice to at-risk relatives. The provision of such advice has been hampered by a lack of appropriate data regarding the cancer risks. Chen and colleagues recently provided precise estimates of the relative risks of breast and ovarian cancer in almost 2000 kindreds with such mutations ascertained through familial cancer clinics across USA. The baseline incidence of breast cancer is lower in Australia than in North America. The relative risks derived from the study have been combined with Australian baseline incidence data to estimate the absolute short-term and long-term risks of breast and ovarian cancers for Australian carriers of different ages. The results are presented as a series of graphs that may be useful in counselling an unaffected carrier of a specified age. It is of note that the incidence of breast cancer in carriers is high in premenopausal women, but approaches the population incidence in postmenopausal women. Conversely, the incidence of ovarian cancer continues to increase from the age of 40 years. Among carriers of BRCA1 or BRCA2 mutations, the cumulative lifetime risk of developing breast cancer is 50-60% and the equivalent risk of ovarian cancer is 20-40%. An unaffected carrier aged 60 years is at greater risk of developing ovarian cancer than breast cancer. These observations have important implications for genetic counselling and decisions regarding prophylactic surgery.     

Occult carcinoma in prophylactic oophorectomy specimens: prevalence and association with BRCA germline mutation status.

Prophylactic oophorectomy (PO) is an option for women at increased risk for ovarian carcinoma. In this study the value of intensive pathologic examination of PO specimens and accompanying resected tissues in the identification of occult carcinoma and any association of occult carcinoma with BRCA germline mutation status were ascertained. Specimens from 60 consecutive PO patients, who were not suspected of having any ovarian tumor at the time of surgery, were subjected to standardized, complete pathologic examination in a prospective study over an 8-year period. Extra-ovarian tissues were examined as well, but they were not subject to the same standardized protocol. Any occult carcinoma of the ovaries or fallopian tubes was noted. The BRCA status and follow-up of patients were obtained, if available. Fifty-five of the 60 PO specimens did not show any evidence of malignancy. Of the 32 patients in this group followed for >1 year, all are alive and well. The remaining five patients, all BRCA1 mutation positive, showed occult carcinoma of the ovaries and/or in situ or invasive carcinoma of a fallopian tube. One of these five patients has died of abdominal carcinomatosis; four continue to be well, but follow-up is <4 years in all cases. Occult carcinoma is present in a small proportion of BRCA-positive or unknown PO patients and may be of prognostic significance. The entire ovaries and tubes from PO patients should be submitted for histologic examination to identify malignancy.     

A case of gastric cancer metastasis to the breast in a female with BRCA2 germline mutation and literature review

Introduction: Gastric cancer is a deadly disease. Common sites of distant metastasis of gastric cancer are the peritoneum, liver, lymph nodes, and lung. The breast is a rare site of metastasis in gastric cancer which occurs in males dominantly.

Patients and methods: Here, we report the first case of metastatic gastric cancer to the breast in a patient with the breast cancer 2 (BRCA2) germline mutation. A 34-year-old female was admitted to the hospital with dyspepsia and a palpable mass in the left breast. Gastric cancer was confirmed to be signet ring cell adenocarcinoma. The breast mass exhibited histological properties consistent with gastric cancer. Immunohistochemistry results showed the breast tumor was CDX-2 and CK20-positive, but ER-, CK7-, and GATA3-negative. The BRCA1 gene had a wild-type sequence, but a heterozygous variant was discovered in BRCA2 in exon 10 (c.1744A?>?C, p.T582P); the significance of this variant is unknown.

Results: The patient received palliative XELOX (capecitabine?+?oxaliplatin) with radiation therapy to the stomach. The breast tumor resolved completely, but the overall response was partial.

Conclusion: Gastric cancer metastasis to the breast is rare, but should be considered in young female patients with signet ring cell type gastric cancer.     

Medullary carcinoma of breast with a novel germline mutation 1123T >G in exon 11 of BRCA1

Breast cancer, the most common malignancy in females, has an estimated 5-10% hereditary predisposition. BRCA1 is a tumor suppressor gene and is known to be responsible for breast cancer and breast-ovarian cancers running in families. In breast caner patients, several mutations in BRCA1 have been reported throughout the gene. This report describes identification of a mutation in BRCA1 gene using protein truncation (PTT) assay in a patient with medullary carcinoma of breast who also had a family history of breast cancer. Following DNA sequencing, the mutation was confirmed as substitution of thymine at position 1123 with guanine of exon 11 (1123 T>G). This mutation can be added to the pool of known BRCA1 mutations in Pakistani population, which will help in developing a local screening panel of BRCA1 mutations.     

Gene therapy for breast and ovarian cancer with BRCA1

As an initial step toward gene therapy for ovarian cancer, we conducted a Phase 1 trial to assess the pharmacokinetics and toxicity of intraperitoneal BRCA1sv retroviral vector therapy. Gene transfer and expression were documented by PCR, southern blot, RT-PCR and nuclease protection assays. Pharmacokinetics were assessed by PCR and southern blots detecting vector DNA, and toxicity was evaluated by clinical exam and fluid analysis. Three of twelve patients developed an acute sterile peritonitis which spontaneously resolved within 48 hours. Plasma and peritoneal antibodies to the retroviral envelope protein were detected only in patients treated with the highest dose levels but not in others, despite repeat dosing for an interval of up to four months. Eight patients showed stable disease for 4 to 16 weeks. Three patients showed tumor reduction with diminished miliary tumor implants at reoperation (two patients) and radiographic shrinkage of measurable disease (one patient). Ovarian cancer may provide an imporant model for retroviral gene therapy studies due to vector stability, minimal antibody response, and access to tumor by intraperitoneal therapy.     

Clinical outcome and toxicity from taxanes in breast cancer patients with BRCA1 and BRCA2 pathogenic germline mutations

Germline variations in genes coding for proteins involved in the oxidative stress and DNA repair greatly influence drug response and toxicity. Because BRCA1 and BRCA2 proteins play a role in DNA damage repair, we postulated that taxane‐related toxicity is potentially higher and clinical outcome in different in patients with BRCA pathogenic variants (PV). Seven hundred nineteen women who underwent BRCA genetic testing and were treated with taxane‐containing chemotherapy for early‐stage breast cancer between 1997 and 2018 were included in the study. Patients with BRCA variants of uncertain significance were excluded. The Kaplan‐Meier product‐limit method was used to estimate recurrence‐free survival (RFS) and overall survival (OS) rates. Logistic regression models were used to assess the association between chemotherapy toxicity and factors of interest. Cox regression models were used to assess the association between RFS and OS and factors of interest. Ninety‐four (13%) and 54 (7%) patients had BRCA1 and BRCA2‐PVs, respectively. While anemia (P = .0025) and leukopenia (P = .001) were more frequently seen in BRCA noncarriers, there was no difference in regards to peripheral neuropathy or other toxicities between the groups. Increasing doses of taxane were associated with increased risk of neutropenia, stomatitis, nausea, vomiting, acne/rash, and peripheral neuropathy across all groups. In a multivariate logistic regression model, BRCA2 status remained as an independent significant predictor for decreased hematologic toxicity (HR: 0.36; 95% CI: 0.20‐0.67; P = .001) and increased gastrointestinal toxicity (HR: 1.93; 95% CI: 1.02‐3.67; P = .04). Being overweight, obese and African‐American race were significant predictors for peripheral neuropathy (P = .04; P = .03; P = .06, respectively). Total taxane dose received did not have any impact on survival outcomes. Our study demonstrates that taxane‐containing chemotherapy regimens do not increase risk of peripheral neuropathy or hematologic toxicity in patients with BRCA PVs. The mechanisms for this finding need to be further investigated as it may provide an opportunity to combine taxanes with other agents, such as platinum salts or PARP inhibitors, with less anticipated toxicity.     

Cumulative risk of second primary contralateral breast cancer in BRCA1/BRCA2 mutation carriers with a first breast cancer: A systematic review and meta-analysis

BRCA1/2 mutation carriers are at a higher risk of breast cancer and of subsequent contralateral breast cancer (CBC). This study aims to evaluate the evidence of the effect of the BRCA1/2-carriership on CBC cumulative risk in female breast cancer patients.The literature was searched in Pubmed and Embase up to June 2013 for studies on CBC risk after a first primary invasive breast cancer in female BRCA1/2 mutation carriers. A qualitative synthesis was carried out and the methodological quality of the studies evaluated. Cumulative risks of CBC after 5, 10 and 15 years since the first breast cancer diagnosis were pooled by BRCA1/2 mutation status.A total number of 20 articles, out of 1324 retrieved through the search, met the inclusion criteria: 18 retrospective and 2 prospective cohort studies. Cumulative risks of up to five studies were pooled. The cumulative 5-years risk of CBC for BRCA1 and BRCA2 mutation carriers was 15% (95% CI: 9.5%–20%) and 9% (95% CI: 5%–14%), respectively. This risk increases with time since diagnosis of the first breast cancer; the 10-years risk increased up to 27% and 19%, respectively. The 5-years cumulative risk was remarkably lower in non-BRCA carriers (3%; 95% CI: 2%–5%) and remained so over subsequent years (5%; 95% CI: 3%–7%).In conclusion, risk of CBC increases with length of time after the first breast cancer diagnosis in BRCA1/2 mutation carriers. Studies addressing the impact of treatment-related factors and clinical characteristics of the first breast cancer on this risk are warranted.     

Post-mastectomy surveillance of BRCA1/BRCA2 mutation carriers: Outcomes from a specialized clinic for high-risk breast cancer patients

Female BRCA1/BRCA2 mutation carriers may elect bilateral risk-reducing mastectomy. There is a paucity of data on yield of imaging surveillance after risk-reducing mastectomy. This retrospective study focused on female BRCA1/BRCA2 mutation carriers who underwent bilateral mastectomy either as primary preventative, or as secondary preventative, after breast cancer diagnosis. All participants underwent breast imaging at 6- to 12-month intervals after mastectomy. Data on subsequent breast cancer diagnosis and timing were collected and compared between the groups. Overall, 184 female mutation carriers (134 BRCA1, 45 BRCA2, 5 both BRCA genes) underwent bilateral mastectomy after initial breast cancer diagnosis, between April 1, 2009 and August 31, 2018. During a mean follow-up of 6.2 ± 4.2 years, 13 (7.06%) were diagnosed with breast cancer; 12 ipsilateral (range: 0.4–28.8 years) and 1 contralateral breast cancer, 15.9 years after surgery. On the contrary, among asymptomatic BRCA1 (n = 40) and BRCA2 (n = 13) mutation carriers who underwent primary risk-reducing mastectomy (mean age at surgery 39.5 ± 8.4 years); none has developed breast cancer after a mean follow-up of 5.4 ± 3.4 years. BRCA1/BRCA2 mutation carriers with prior disease who underwent risk-reducing mastectomy after breast cancer diagnosis are still prone for developing ipsi or contralateral breast cancer, and therefore may benefit from continues clinical and imaging surveillance, unlike BRCA1/BRCA2 mutation carriers who undergo primary preventative bilateral mastectomy.     

Male BRCA1 and BRCA2 mutation carriers: a pilot study investigating medical characteristics of patients participating in a prostate cancer prevention clinic

BACKGROUND: Male BRCA1 and BRCA2 mutation carriers are at an increased risk to develop prostate cancer and are subject to screening protocols for high-risk men. The utility of targeted screening, and the clinical and pathological features associated with prostate cancer, have received little attention in this population. METHODS: We report on the clinical screening and pathological characteristics of a group of 19 men with BRCA1 or BRCA2 mutation, as compared to an age-matched group of men with a family history of prostate cancer. RESULTS: Mutation carriers were significantly more likely to have an elevated PSA at first visit (P = 0.03). Prostate cancer was twice as likely to be diagnosed in mutation carriers although this difference was not statistically significant (P = 0.55). CONCLUSIONS: Prostate cancer surveillance of BRCA1 and BRCA2 mutation carriers is warranted. Further research on larger cohorts is needed to evaluate whether unique pathological prostate cancer characteristics exist in these men.     

Management of breast cancer risk in BRCA1/2 mutation carriers who are unaffected with cancer

Pathogenic mutations in BRCA1 and BRCA2 genes markedly increase the risk of breast cancer and other cancers such as ovarian/fallopian tube, pancreatic, prostate, and melanoma. Patients with BRCA1 mutations have a slightly higher lifetime risk of breast cancer than BRCA2 mutation carriers, and both BRCA1 and BRCA2 carriers tend to develop breast cancer at an earlier age than the general population. In this review, we will discuss management recommendations to reduce breast cancer risk for BRCA1/2 mutation carriers including special populations of carriers such as pregnant or lactating patients and men. Breast cancer screening, including clinical breast examination, mammogram, and breast MRI, is important for detecting breast cancer at an early and likely curable stage. In addition to screening, counseling on risk‐reducing surgeries is strongly recommended for BRCA1/2 carriers. Risk‐reducing mastectomy decreases the risk of breast cancer development, and risk‐reducing salpingo‐oophorectomy decreases ovarian cancer‐specific as well as overall mortality, but controversy exists regarding its impact on breast cancer‐specific mortality. Given the effectiveness of screening for breast cancer, further management should be carried out on an individual basis taking into account quality of life and psychosocial factors, and recommendations should be readdressed periodically as science progresses and patients’ goals may change.     

BRCA1和BRCA2在胶东半岛地区女性散发性乳腺癌中的表达研究

Objective To study the expression and clinical significance of BRCA1 and BRCA2 in sporadic breast cancer in women of Jiaodong peninsula. Methods Immunohistochemistry and tissue array were used to detect the expression of BRCA1 and BRCA2 in 100 cases of sporadic breast cancer and 30 cases of benign breast tumor in women of Jiaodong peninsula. Results ① The expression rate of BRCA1 and BRCA2 was 49% (49/100) and 50% (50/100) in breast cancer, 80% (24/30) and 83.33% (25/30) in benign breast lesions respectively. The expression rate of BRCA1 and BRCA2 in breast cancer was lower than that in benign breast lesions (P<0.05). ② The expression of BRCA1 and BRCA2 was uncorrelated with factors such as tumor size, lymphatic metastases, age and menopause or not(P>0.05). ③ There was no dependency between the expression of BRCA1 and BRCA2 (P> 0. 05). Conclusions The expression rate of BRCA1 and BRCA2 in breast carcinoma in women of Jiaodong peninsula was lower than that in benign breast lesions, suggesting that the expression of BRCA1 and BRCA2 was related to the occurrence of sporadic breast carcinoma in women of Jiaodong peninsula. However, the role of BRCA1 and BRCA2 in the genesis and development of the breast carcinoma is independent.     

Medical Management of newly diagnosed breast cancer in a BRCA1/2 mutation carrier

Germline BRCA1/2 mutations may be infrequent in unselected breast cancer population but are concentrated in those with triple‐negative breast cancer or high‐risk family history. Insight into the biology of BRCA mutation is now allowing a targeted therapeutic approach to these carriers with breast cancer. Functional BRCA genes play a critical role in DNA damage repair. Agents such as platinum salts and poly (ADP‐ribose) polymerase (PARP) inhibitors exploit this vulnerability of impaired DNA damage repair mechanism in BRCA mutant cancers to leverage therapeutic benefit. Research has demonstrated improved response rates to platinum salts in BRCA‐mutated compared with non‐BRCA‐mutated breast cancer, particularly in the metastatic setting. Additionally, clinical trials of single‐agent PARP inhibitors have shown encouraging response rates and progression‐free survival in patients with BRCA1/2‐mutated breast cancer. In this review, we summarize the medical management of BRCA‐associated breast cancer.     

Risk management decisions in women with BRCA1 and BRCA2 mutations

Introduction

Pathogenic mutations and variants of uncertain significance (VUS) occur in BRCA1/2 genes.

Higher antitumor activity of trabectedin in germline BRCA2 carriers with advanced breast cancer as compared to BRCA1 carriers: A subset analysis of a dedicated phase II trial

Specific alkylators may allow synthetic lethality among patients with germline BRCA1/2-mutations related cancers. The tetrahydroisoquinolone trabectedin administered at 1.3 mg/m² as a 3-h intravenous infusion every 3 weeks showed activity in patients with pretreated metastatic breast cancer (MBC) and BRCA germline mutations, but mainly in BRCA2 carriers. Data from a phase II study were retrospectively analyzed to compare the efficacy and safety of this trabectedin dose and schedule in pretreated MBC patients bearing germline BRCA1/2 mutations. The primary efficacy endpoint was the objective response rate (ORR) as per Response Evaluation Criteria In Solid Tumors (RECIST) by independent expert review. Duration of response (DR) and progression-free survival (PFS) were secondary efficacy endpoints. Safety was evaluated using the National Cancer Institute Common Toxicity Criteria (NCI-CTC). Data from 26 BRCA1-mutated and 13 BRCA2-mutated patients were analyzed. 69% of BRCA1-mutated cancers were triple-negative vs. 31% of BRCA2-mutated ones. 77% of BRCA1 and 31% of BRCA2 carriers were platinum-pretreated. The ORR in BRCA2-mutated patients was higher than in BRCA1-mutated patients (33.3% vs. 9.1%). DR ranged for 1.4–6.8 months in BRCA2-mutated patients and for 1.5–1.7 months in BRCA1-mutated patients. More BRCA2-mutated patients had disease stabilization for ≥4 months (25.0% vs. 9.1%) and their median PFS was longer (4.7 vs. 2.5 months). Trabectedin was well tolerated in both patient subtypes. In conclusion, trabectedin showed higher antitumor activity in relapsed MBC patients with germline BRCA2 mutations than in those with BRCA1 mutations.