Incidence Of Bilateral Breast Cancer Research Articles

Association of Moderate-Risk Breast Cancer Genes with Contralateral Prophylactic Mastectomy and Bilateral Disease.

The impact of ATM, CHEK2, and PALB2, the three most prevalent moderate-risk breast cancer genes, on surgical decision making is not well known. Our retrospective study included patients with resectable non-metastatic breast cancer who underwent multigene panel testing between July 2014 and January 2020 with at least one genetic alteration (pathogenic or variant of uncertain significance [VUS] in ATM [n = 49], CHEK [n = 57], or PALB2 [n = 27]). Our objectives were to determine the rate of contralateral prophylactic mastectomy (CPM) and the rate of bilateral breast cancer. Univariable analyses (UVA) and multivariable analyses (MVA) were performed to identify factors associated with CPM and bilateral breast cancer. The rate of CPM was 39% (n = 49/127), with 54% (n = 25/46) of patients with a pathogenic mutation and 30% (n = 24/81) of patients with a VUS choosing CPM. On MVA, premenopausal status (odds ratio [OR] 3.46) and a pathogenic alteration (OR 3.01) were associated with increased use of CPM. Bilateral disease was noted in 16% (n = 22/138). Patients with pathogenic mutations had a 22% (n = 11/51) incidence of bilateral breast cancer, while patients with VUS had a 13% (n = 11/87) incidence, although this was not statistically significant on UVA or MVA. On MVA, premenopausal status was associated with a decreased risk of bilateral disease (OR 0.33, p = 0.022). During follow-up, a breast cancer event occurred in 16% (n = 22/138). Our study identified a high rate of CPM among those with ATM, CHEK2, and PALB2 alterations, including VUS. Further studies are needed to clarify reasons for CPM among patients with moderate-risk alterations.

Bilateral Breast Cancer: Clinical Profile and Management.

There is paucity of literature regarding the demography, histopathology, management, and outcomes of bilateral breast cancer (BBC). We present our experience of treating 127 BBC with multimodality management. An audit of prospectively maintained computerized breast cancer database of the department of surgical oncology at a tertiary care center was performed. Demography, clinical profile, molecular sub-types, treatment patterns, and outcomes were analyzed. A total 127 patients presented with BBC between 1992 and 2019. Ninety-four had metachronous (MBBC) and 33 had synchronous breast cancer (SBBC). Most contralateral breast cancer (CBC) patients had early-stage breast cancer in comparison to the index side cancer (37% vs 32%). Ninety-four patients underwent bilateral mastectomy and only 18 patients underwent bilateral breast conservation. Seventy-one patients undergoing BCS and surgery for LABC were given postoperative radiotherapy. All patients received adjuvant chemo- and/or hormonal therapy both for index and CBC based on the stage and hormone receptor status. Thirty-three percent of patients had either locoregional or distant relapse. The 5-year overall survival (OS) and 5-year disease-free survival (DFS) of the entire cohort were 86.6% and 68.4% respectively. There was no difference in the OS and DFS between SBBC and MBBC. The incidence of BBC is expected to increase with effective diagnostic and therapeutic interventions and improving survival. Patients require individualized treatment planning in a multidisciplinary treatment setting.

Clinicopathological features and prognosis of bilateral breast cancer: a single-center cohort study based on Chinese data.

BackgroundThe incidence of bilateral breast cancer (BBC) is low, accounting for 5% of patients with breast cancer. This study aimed to investigate the clinicopathological features and prognosis of synchronous bilateral breast cancer (SBBC) and metachronous bilateral breast cancer (MBBC) in the Chinese population.MethodsPatients with BBC, including SBBC and MBBC, were selected from 6,162 breast cancer patients who underwent surgery at the Chinese People’s Liberation Army (PLA) General Hospital between January 2007 and December 2019. Furthermore, patients with unilateral breast cancer (UBC) who underwent surgery at the same time were randomly selected at a ratio of 1:2 as the control group. Clinicopathological features and prognosis were compared between the groups.ResultsIn all, 123 (2.0%) patients with BBC were enrolled in this study, including 98 (1.6%) SBBC and 25 (0.4%) MBBC patients. A total of 280 patients with UBC were selected for the control group. Compared with patients with UBC, patients with SBBC were more likely to be older and have a family history of breast cancer, non-infiltrative carcinoma, lower pathological tumor-node-metastasis (pTNM) stage, and luminal A type breast cancer as their first tumor. Patients with MBBC were more likely to be postmenopausal and have hormone receptor [estrogen receptor (ER)/progesterone receptor (PR)] negativity, a higher pTNM stage, and a triple-negative first tumor. Patients with UBC with ER/PR (−) were more likely to develop contralateral breast cancer (CBC) than those with ER/PR (+). There was no significant difference in overall survival (OS) and disease-free survival (DFS) between patients with SBBC and patients with UBC. Patients with MBBC had worse DFS than those with UBC, but OS was similar for both types of patients. Patients with MBBC <55 years at first diagnosis had significantly shorter DFS compared to those with SBBC and UBC. A multivariate Cox proportional hazards model revealed that age ≥55 years and ER/PR negativity of the first tumor were independent risk factors for OS. Independent risk factors for DFS included MBBC, age <55 years, family history of other malignant tumors, ER/PR (−), lymphovascular invasion, and N stage ≥2 of the first tumor.ConclusionsThe OS and DFS of patients with SBBC and UBC were similar. The MBBC patients, especially those <55 years old at first diagnosis, had shorter DFS than patients with UBC.

Clinical characteristics and the associated risk factors of the development of bilateral breast cancers: A case-control study

BackgroundThe clinical impacts of bilateralism on prognosis and clinical decision-making remain contradictory particularly in areas with low incidence and delayed diagnosis of primary breast cancer. Identification of women at risk of bilateral breast cancer is required to improve patient management and to design the appropriate surveillance. MethodsA total of 1083 women were enrolled and analyzed for the presence of synchronous and metachronous bilateral breast cancer as cases and unilateral breast cancer as controls during the median follow-up of 4.8 years. ResultsThe incidence of bilateral breast cancer was 7.5% (81 of 1083). In comparison with unilateral breast cancers, bilateral cases were significantly diagnosed in younger women (P = 0.037, mean age was 35.6 years) who had a larger tumor size (P = 0.012, mean tumor size was 8 cm in diameter). Histological type of lobular cancer was identified as one of the risk factors for the development of contralateral breast cancer (OR 5.564, 95% CI: 3.219–9.620) and synchronous bilateral breast cancer (OR 2.561, 95% CI: 1.182–5.550). Bilateral breast cancer had significantly shorter progression-free survival (Mean survival was 26.6 vs 52.5 months for bilateral and unilateral breast cancers, respectively; P = 0.001) and shorter time to develop distant metastasis (Mean survival was 41.7 vs 104 months for bilateral and unilateral breast cancers, respectively; P = 0.001). ConclusionPatients with first primary breast tumors with lobular histological type and advanced stages were observed to have higher risks for the development of contralateral breast cancers.

Análise de carcinomas mamários bilaterais: Um perfil das pacientes de um serviço de referência

Introduction: Bilateral breast cancer (BBC) is a rare clinical entity. This pattern of neoplasia can be considered synchronous (simultaneous) or metachronous (1 month to 1 year later). Objective: To select cases of BBC patients seen at HC-UFPR and to recognize in these patients clinical and family characteristics, histological and immunohistochemical patterns, and incidences of synchronous/metachronous occurrences. Method: An observational and analytical study of BBC cases of patients treated at HC-UFPR, from January 2003 to October 2019, based on the analysis of medical records, was developed. Result: 42 patients with BBC were selected and 4 patients were excluded from the study due to incomplete information in the medical record. The incidence of BBC in the surveyed period was 3.64%. All patients are women with a mean age of 51.82 years. White ethnicity is the most prevalent one (82%). With regard to menopausal status, 42% of the subjects are pre-menopausal and 58%, post-menopausal. Regarding parity, only 16% were nulliparous. Half of the patients have a positive family history for neoplasms, with breast cancer present in 46%, ovarian cancer in 16%, and other topography in 68%. In this sample, the synchronous tumor was present in 55% of the patients and the metachronous tumor in 45%. Regarding the patients’ initial clinical staging, 61% presented with locally advanced tumor at the first consultation. In the group of synchronous tumors, the ductal type was the most frequent one (93%), followed by the lobular type (7%). Regarding immunohistochemical subtypes, patients had Luminal B tumors (43%), followed by HER (29%), Triple negative (24%), and Luminal A (5%). Comparing the immunohistochemical profile in both tumors, 62% were in agreement and 48%, in disagreement. In the group of metachronous tumors, the mean time between the diagnosis of the first tumor and that of the second tumor was 5.68 years. The most common histological type was ductal carcinoma (73%), followed by lobular carcinoma (11%), medullary carcinoma (9%), and metaplastics (7%). Regarding the immunohistochemical profile, the most present was Luminal B in 32%, Luminal A in 29%, Triple negative in 24%, and HER 2 in 15%. The immunohistochemical profile was consistent in only 29% of the patients. Conclusion: In this sample, BBC is associated with relevant family history, with a pattern of presentation, synchronous; frequently, ductal is histological and Luminal B is immunohistochemistry.

Synchronous and metachronous bilateral breast cancer: clinicopathologic characteristics and prognostic outcomes

The incidence of bilateral breast cancer (BBC) reportedly ranges from 1.4 to 11.8%. Women with a first primary breast cancer are at a 2- to 6-fold increased risk of developing contralateral BC. However, there have been limited studies analyzing the clinicopathologic features of BBC and conflicting data exist on the prognostic significance of BBC. In this study, we sought to analyze the incidence of BBC in the era of modern medicine and assess the clinicopathologic characteristics and prognostic outcomes compared to unilateral BC (UBC). Of the 5941 patients with stage I-III BC diagnosed between 1998 and 2013 at our institution, 110 developed BBC, including 58 synchronous BBC (SBBC, interval between the first and the contralateral BC ≤3 months) and 52 metachronous BBC (MBBC, interval >3 months). The median time to the second tumor was 67.9 months among patients with MBBC. BBC was associated with a significantly lower rate of having a ductal type, high grade, HER2-positive or node-positive disease when compared to UBC, while no difference was found for age, race, ER/PR status, or pathologic tumor stage. When compared to MBBC, SBBC was strongly associated with a lobular phenotype, non-high grade, and ER/PR-positive disease; and further demonstrated a significantly higher concordant rate for ER, PR, and HER2 status. Patients with BBC had a significantly worse distant relapse-free survival (RFS) but a similar disease-specific survival (DSS) when compared to those with UBC. Being African American, having a high histologic grade and higher pathologic tumor or node stage was significantly associated with a worse prognosis, while SBBC was associated with a favorable RFS by multivariate analysis. Nodal status was the only independent prognosticator for DSS in patients with BBC. Further investigation into the complex biologic and clinical behavior of BBC may provide novel insights into the therapeutic strategies in the pursuit of precision medicine in this unique subset of patients.

The prognostic comparison among unilateral, bilateral, synchronous bilateral, and metachronous bilateral breast cancer: A meta-analysis of studies from recent decade (2008-2018).

BackgroundThe incidence of bilateral breast cancer (BBC) is increasing nowadays comprising 2%‐11% of all breast cancer (BC). According to the interval time between the first and second cancer, BBC could be divided into synchronous (SBBC) and metachronous (MBBC). However, this interval time is quite different across studies. It remains controversial whether the survival of BBC, SBBC, and MBBC is similar or worse compared to that of unilateral breast cancer (UBC), and whether the survival of SBBC is similar or worse compared to MBBC. To better understand the survival of UBC, BBC, SBBC, and MBBC and how the interval time would influence the prognosis of SBBC and MBBC, we performed this meta‐analysis on studies from recent 10 years (2008‐2018).MethodsDatabases of PubMed, Embase, and Web of Science were searched for relevant studies within recent 10 years. Hazard ratio (HR) was adopted to evaluate the difference of overall survival (OS) of UBC, BBC, SBBC, and MBBC. HR of OS comparisons were performed between BBC vs UBC, SBBC vs UBC, MBBC vs UBC, and SBBC vs MBBC with 3, 6, 12 months as the interval time, respectively.ResultsThere were 15 studies of 72 302 UBC and 2912 BBC included in the meta‐analysis. The summary HR of OS comparison between BBC vs UBC was 1.68 (95% CI: 1.28‐2.20), SBBC vs UBC was 2.01 (95% CI: 1.14‐3.55), MBBC vs UBC was 3.22 (95% CI: 0.75‐13.78). When 3, 6, 12 months were used as the interval time, the summary HR of the OS comparison between of SBBC vs MBBC were 0.64 (95% CI: 0.44‐0.94), 1.17 (95% CI: 0.84‐1.63) and 1.45 (95% CI: 1.10‐1.92), respectively.ConclusionBBC and SBBC showed worse prognosis in terms of OS compared to UBC while MBBC manifested similar or non‐superior survival as UBC. The OS comparison between SBBC and MBBC changed with different interval time used. The longer the interval time used, the worse the survival of SBBC. SBBC with interval of 3‐12 months between the two cancers had the worst prognosis. When 6 months was used to differentiate SBBC from MBBC, these two clinical entities showed similar OS.

Abstract P1-08-12: Trends in incidence of bilateral breast cancer: A Population-based comparative study of the United States and Japan

Abstract Background: Previous studies demonstrated that the incidence rate of invasive contralateral breast cancer (CBC) was 5% within the first 10 years after the primary breast cancer (BC). However improving long-term breast cancer survivorship and advancements in diagnostic imaging have resulted in an increased detection of bilateral breast cancer (BBC), and trends of bilateral invasive and in situ breast cancer are not well established. The aim of this study was to assess national trends of BBC incidence of the United States (US) and Japan. Methods: The Surveillance, Epidemiology, and End Results (SEER) database (1973-2014) and the clinical database of Breast Oncology Center of Cancer Institute Hospital in Tokyo, Japan (Ganken) database (1946-2015) were used to identify nSEER=11,771 and nGanken=1,499 women diagnosed with BBC, respectively. BBC was defined as invasive BC and/or ductal or lobular carcinoma in situ diagnosed in both breasts simultaneously or after primary breast cancer diagnosis. BBC was grouped into synchronous or metachronous BBC by the interval between first BC and contralateral BC; synchronous cases were defined as CBC diagnosed at the same time or within an interval of 1 year from primary BC diagnosis whereas metachronous cases were defined as a diagnosis occuring 1 year following the primary BC. We assessed trends of BBC incidence and characteristics of BBC cases between the two countries. To determine temporal trends in the incidence of BBC and proportion of the characteristics, we compared them using the Cochrane-Armitage test for trend. Results: The rates of BBC have significantly increased in both countries (Table 1, 2) [1975: 2.6%; 2014: 7.5% in SEER (p&amp;lt;0.001), 1946-1980: 3.3%; 2011-2015: 10.7% in Ganken (p&amp;lt;0.001)]. The increase was identified in both synchronous and metachronous BBC. In SEER, 40% of synchronous BBC were found as in situ BC and about 15% of BBC presented as invasive lobular carcinoma. More recently, CBC was more likely to be diagnosed at early stages (in situ and local disease) than in previous years [1975: 65%; 2014: 85% in SEER (p&amp;lt;0.001)]. The interval between first BC and contralateral BC have shortened, and CBC were more likely to be operated simultaneously in both countries [1985: 40%; 2014: 51% in SEER, 1946-1980: 24%; 2011-2015: 74% in Ganken]. [Table 1]Crude rates of BBC in all breast cancer in SEER 19751985199520052014All breast cancer941813618258766016471505BBC and rates (%)249 (2.6%)790(5.8%)1421(5.5%)3336(5.6%)5381(7.5%)Rates of synchronous BC2.1%2.8%2.3%2.6%3.5%Rates of metachronous BC0.5%3.0%3.2%3.0%4.0%BBC: Bilateral breast cancer [Table 2]Crude rates of BBC in all breast cancer in Ganken 1946-19801981-19851991-19952001-20052011-2015All breast cancer47772162280637915241BBC and rates (%)157(3.3%)110(5.1%)188(6.7%)298(7.9%)559(10.7%)Rates of synchronous BC1.0%1.9%2.0%2.7%4.9%Rates of metachronous BC2.3%3.2%4.7%5.2%5.8% Conclusion: In the modern era, the number of BBC cases have increased and are more likely to be found at an early stage. Further studies are needed to demonstrate the usefulness of early detection of CBC and to define the best means to tailor therapy for patients with bilateral disease. Citation Format: Sakai T, Ozkurt E, Desantis S, Wong S, Rosenbaum L, Zheng H, Ohno S, Golshan M. Trends in incidence of bilateral breast cancer: A Population-based comparative study of the United States and Japan [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-08-12.

Abstract P3-10-13: Bilateral breast cancer in China: A 10-year single-center retrospective study

Abstract BACKGROUD: Women with unilateral breast cancer are at increased risk for developing contralateral disease. The objective of the single-center retrospective study was to evaluate the incidence of bilateral breast cancer (BBC) and to analyze the clinicopathological characteristics for BBC in China. METHODS: We retrospectively reviewed the electronic medical records of 3924 female patients with breast cancer consecutively treated at the department of Breast Oncology in the Peking University Cancer Hospital between 2006 and 2016. BBC was categorized as synchronous (within 6 months) or metachronous bilateral breast cancer (after 6 months of a first tumor). Patients with BBC were identified according to the criteria described by Chaudary et al. Patients with stage IV first breast cancer, and those who were found to have distant metastases between the first and second primary breast cancer were excluded. Analyses of demographic, clinicopathologic, and treatment characteristics were done between sBBC and mBBC. RESULTS: The incidence of BBC in our population was 3.2% (127 of 3924). Of those, 2.5 % ( 99 of 3924) were metachronous bilateral breast cancer ( mBBC ), and 0.71 % (28 of 3924) were synchronous bilateral breast cancer ( sBBC ). The overall median age of the patients at first diagnosis was 45 years (range, 27-81 years). The age of onset of the first mBBC was significantly younger than that of sBBC ( p = 0.027). In mBBC subgroups, the median time interval between first and second tumors was 68 months (range, 7-342 months), and 80.8% of the second tumor were diagnosed within 10 years of the diagnosis of the first tumor. A positive family history of breast cancer was found in 25% of sBBC and 9.1% of mBBC ( p = 0.025). In ER-negative first tumor of mBBC, 56.1% of the second tumor were ER-positive. Mastectomy was the commonest surgery performed in these patients. CONCLUSIONS: Our results confirmed the necessity of screening contralateral breast at the diagnosis of unilateral breast cancer and following-up for Chinese patients with breast cancer. Citation Format: Li H, Jiang H, Zhang R, Shao B, Yan Y, Ran R, Di L. Bilateral breast cancer in China: A 10-year single-center retrospective study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-10-13.

Detection of Bilateral Breast Cancer at Biennial Screening Mammography in the Netherlands: A Population-based Study

To determine the incidence of bilateral breast cancer at biennial screening mammography and to assess the sensitivity of screening in the detection of bilateral breast cancer. All women gave written informed consent, and the requirement to obtain review board approval was waived. The authors included all 302,196 screening mammograms obtained in 80,466 women aged 50-75 years in a southern breast screening region of the Netherlands between May 1998 and July 2008. During 2-year follow-up, the authors collected clinical data, breast imaging reports, biopsy results, and breast surgery reports from all patients with screening-detected and interval cancers. Two screening radiologists reviewed the screening and clinical mammograms of all bilateral screening-detected and interval cancers for mammographic abnormalities. The radiologists were initially blinded to each other's referral opinion, and discrepant assessments were followed by consensus reading. Of all women with screening-detected cancer (n = 1555) or interval cancer (n = 585), 52 (2.4%) had bilateral breast cancer. The sensitivity of screening mammography in the detection of bilateral breast cancer was 19% (10 of 52 women; 95% confidence interval: 8.5%, 29.9%). At blinded review, 18 of the 53 tumors not detected at screening (34%) were considered to be missed, 11 (21%) showed nonspecific minimal signs, and 24 (45%) had been mammographically occult at screening. Five women referred for further analysis experienced a 6-17-month delay in the diagnosis of the second breast cancer; in four of those women, the delay resulted from an incorrect Breast Imaging Reporting and Data System classification at clinical mammography. The sensitivity of screening mammography in the detection of bilateral breast cancer is disappointingly low. Both screening radiologists and clinical radiologists should pay vigorous attention to the contralateral breast to detect bilateral malignancies without diagnostic delay.

Bilateral Breast Cancer: Analysis of Incidence, Characteristics and Outcome of the Disease.

Abstract Background: Despite the widespread adoption of breast conservation therapy in breast cancer, there is a dramatic increase in the rate of bilateral mastectomy in USA. The aim of this study was to address the incidence of bilateral breast cancer (BBC) and to investigate its characteristics, survival and outcome compared to unilateral breast cancer.Methods: Data was acquired from the prospectively maintained NUI Galway breast cancer database between 1988 and 2008. BBC were then categorized as synchronous (within 12 months) or metachronous cancer (after 12 months of first tumour). SPSS was used for data analysis.Results: The incidence of bilateral breast cancer in our population was 4.4% (112 of 2524). Of those 2.1% were synchronous while 2.3% were metachronous. Compared to unilateral cases, bilateral cancer patients were younger (0=0.021) and had smaller size (p=0.001) and earlier stage (p&amp;lt;0.001) tumours at diagnosis. There were no differences in histological type (p=0.630) and grade (p=0.054)). While there was no significant difference in survival for patients with bilateral compared to unilateral tumour (p&amp;gt;0.05), the synchronous bilateral tumour was associated with poor overall survival (p=0.010) and disease free survival (p=0.013) in comparison to metachronous bilateral tumour.Conclusion: We observed significant differences in bilateral tumour characteristics compared to unilateral disease. Although bilateral synchronous tumour was associated with poor outcome and overall survival, patients with metachronous disease do as well as patients with unilateral tumour. The increasing practice of bilateral mastectomy is not supported by this large single centre experience. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5033.

Bilateral breast cancer

17073 Background: The clinical significance of bilateral breast cancer is unclear and its influence on prognosis is controversial. The aim of this study is to assess the impact of bilateral breast cancer on the prognosis compared with unilateral breast cancer and examine clinicopathologic characteristics of Bilateral and Unilateral breast cancer. Methods: 108 patients included in this study from Jan 1980 to Dec 2005 and all information regarding medical and family history of breast cancer came from medical records and questionnaires. Results: There were 108 patients with bilateral breast cancer and its incidence was 2.3% of total breast cancer. The incidence of bilateral breast cancer after 1998 was 3.5% (90/2548) compare with the incidence before 1998 (0.9%). The mean age of patients with bilateral and unilateral breast cancer was 45.34 and 47.54 years, respectively. (p=0.032) Compared to unilateral breast cancer, bilateral group did not differ in gravida, marital status, use of HRT, but the number of case which was diagnosed with breast cancer among close relatives was more frequent (7 cases/6.5% vs 126 cases/2.8%, p=0.024). Although the most frequent histopathologic subtype was ductal carcinoma in both groups, the distribution of the histopathologic subtypes was different between the groups as invasive lobular carcinoma was present in a higher percentage of patients with bilateral breast cancer than in patients with unilateral breast cancer (6.5% vs 2.1%, p=0.002). It suggested that risk factors of developing bilateral breast cancer were family history, lobular tumor, use of hormonal therapy based on the result of multivariate regression analysis. There were no statistically significant difference in 5-year disease free survival and overall survival in both groups (bilateral: 83.25%, 89.52% vs unilateral: 82.74%, 88.79%), (p=0.3934, p=0.3114). Conclusion: In lobular carcinoma patients with family history of breast cancer during follow-up, the possibility of contralateral breast cancer should be considered more carefully and the therapeutic strategy for secondary tumor should resemble the treatment procedure for the primary tumor. No significant financial relationships to disclose.

Genetic implications of bilateral breast cancer: a population based cohort study

Women with breast cancer are at high risk of bilateral breast cancer. We aimed to assess the incidence of bilateral breast cancer in relation to age and time since diagnosis of first cancer. We analysed a population-based cohort of 123757 women with a first primary breast cancer diagnosed in Sweden from 1970 to 2000 for frequency of bilateral breast cancers and deaths by means of record linkage. Second primary breast cancers were categorised as synchronous bilateral breast cancers if diagnosed within 3 months of the first primary cancer or as metachronous if diagnosed more than 3 months after diagnosis of first primary cancer. We identified 6550 women who had developed bilateral breast cancer. Age-incidence patterns of synchronous and unilateral breast cancer were similar, although the absolute rates of synchronous bilateral cancer were 50-100 times lower than those of unilateral cancer. A woman aged 80 years or older is at least twice as likely to be diagnosed with synchronous bilateral breast cancer than is a woman younger than 40 years. In the first 20 years after diagnosis of primary breast cancer, incidence of metachronous bilateral cancer decreased from about 800 per 10(5) person-years to 400 per 10(5) person-years in patients diagnosed with primary breast cancer before the age of 45 years, whereas incidence remained at 500-600 per 10(5) person-years in those age 45 years or older at diagnosis. After 30 years' follow-up, cumulative risk of metachronous bilateral breast cancer was about 15% irrespective of age at first primary breast cancer. The higher than expected risk of synchronous bilateral breast cancer could be explained by non-genetic factors. By contrast, incidence of metachronous bilateral cancer fits neither a model of highly penetrant genes nor aggregation of environmental risk factors.

BRCA1 and BRCA2 mutations as prognostic factors in bilateral breast cancer patients

Incidence of primary bilateral breast cancer (BC) is rare and does not exceed 5%. BRCA1/2 mutation carriers diagnosed with breast cancer have a strong life time risk of developing contralateral breast cancer (53% versus 2%). A group of 108 patients with bilateral breast cancer, who reported at our Cancer Centres from 2000 to 2002, were subjected to genetic testing. Similarities and differences between BRCA1/2 carriers and non-carriers were analysed in terms of family history, pathology of tumour, age of diagnosis, developing contralateral BC and second primary cancer. BRCA1/2 mutations were detected in 32 of 108 patients. Family history of BC was identified in 46.9% of these patients compared with 22.4% of non-carriers (P <0.05). Synchronous BC was diagnosed significantly rarer [4 of 32 (12.5%)] in BRCA1/2 carriers than in the non-carrier group [26 of 76 (34.2%)]. In addition, patients with BRCA mutations were younger when they were diagnosed than non-carriers. BRCA1/2 carriers had a significantly higher incidence of medullary BC (13.6% versus 1.7%) and developed ovarian cancer significantly more frequently than non-carriers (12 of 32 and 1 of 72 patients, respectively). Patients with bilateral BC having BRCA mutations are significantly younger than non-carriers. They also have a significantly higher family history of BC and an increased risk of developing ovarian cancer. The differences in clinical aspects of BRCA carriers with bilateral BC should be considered in clinical management.

BRCA1/2 mutations as prognostic factors in bilateral breast cancer (BC) patients

9647 Background: Incidence of primary bilateral BC is rare and not extending 5%. BRCA1/2 mutation carriers diagnosed with BC have a strong life time risk of developing a contralateral BC (53% vs 2%). Methods: We analyzed the group of 108 patients with bilateral BC who attended our Cancer Center between 2000 and 2002 and who gave their consent for genetic test. Patients with synchronous BC were defined as having contralateral BC within 1 year. Similarities and differences between BRCA1/2 carriers and non carriers were analyzed in terms of family history, pathology of tumor, age of diagnosis and development of contralateral BC and second cancer. Results: The median age of the group at the time of diagnosis of BC was 47 years (28–76). Before age of 50, BC developed 73% of patients, including 22% before age of 40. Synchronous BC was diagnosed in 30 (28%) patients, metachronous in 78 (72%). Family history of BC was present in 32/108 patients, and of ovarian cancer in 5/108 patients. BRCA1/2 mutation was detected in 32/108 patients. Family history of BC was identified in 46,9% of these patients, comparing to 22,4% of non carriers (p<0.05). Synchronous BC was diagnosed significantly rarer 4/32 (12.5%) in BRCA1/2 carriers than in non carriers group 26/76 (34.2%). Also patients with BRCA mutations when diagnosed were younger than non carriers (41.3 vs 47.9) and time to diagnosis of contralateral BC was shorter. BRCA1/2 carriers had significantly higher incidence of medullary BC (13.6% vs 1.7%). There was no difference in the incidence of other tumor pathology. BRCA1/2 carriers developed significantly more frequent ovarian cancer than non carriers 12/32 and 1/72 respectively. Conclusions: Patients with bilateral BC having BRCA mutations are significantly younger, than non carriers and time of developing of contralateral BC is shorter.They have significantly more frequent family history of BC and higher risk of developing of ovarian cancer. The differences in clinical aspects of BRCA carriers with bilateral BC, should be considered in clinical management. No significant financial relationships to disclose.

BRCA1/2 mutations as prognostic factors in bilateral breast cancer (BC) patients

9647 Background: Incidence of primary bilateral BC is rare and not extending 5%. BRCA1/2 mutation carriers diagnosed with BC have a strong life time risk of developing a contralateral BC (53% vs 2%). Methods: We analyzed the group of 108 patients with bilateral BC who attended our Cancer Center between 2000 and 2002 and who gave their consent for genetic test. Patients with synchronous BC were defined as having contralateral BC within 1 year. Similarities and differences between BRCA1/2 carriers and non carriers were analyzed in terms of family history, pathology of tumor, age of diagnosis and development of contralateral BC and second cancer. Results: The median age of the group at the time of diagnosis of BC was 47 years (28–76). Before age of 50, BC developed 73% of patients, including 22% before age of 40. Synchronous BC was diagnosed in 30 (28%) patients, metachronous in 78 (72%). Family history of BC was present in 32/108 patients, and of ovarian cancer in 5/108 patients. BRCA1/2 mutation was detected in 32/108 patients. Family history of BC was identified in 46,9% of these patients, comparing to 22,4% of non carriers (p<0.05). Synchronous BC was diagnosed significantly rarer 4/32 (12.5%) in BRCA1/2 carriers than in non carriers group 26/76 (34.2%). Also patients with BRCA mutations when diagnosed were younger than non carriers (41.3 vs 47.9) and time to diagnosis of contralateral BC was shorter. BRCA1/2 carriers had significantly higher incidence of medullary BC (13.6% vs 1.7%). There was no difference in the incidence of other tumor pathology. BRCA1/2 carriers developed significantly more frequent ovarian cancer than non carriers 12/32 and 1/72 respectively. Conclusions: Patients with bilateral BC having BRCA mutations are significantly younger, than non carriers and time of developing of contralateral BC is shorter.They have significantly more frequent family history of BC and higher risk of developing of ovarian cancer. The differences in clinical aspects of BRCA carriers with bilateral BC, should be considered in clinical management. No significant financial relationships to disclose.

Synchronous, bilateral breast cancer: prognostic value and incidence

The purpose of this study was to address the question whether patients with bilateral breast cancer (BBC) have a worse prognosis in terms of recurrence and survival than patients with primarily unilateral breast cancer (UBC) following breast-conserving treatment (BCT). From 1983 to 2000, a total of 1760 BCT were registered in the Radiotherapy Department of the Medisch Spectrum Twente. We defined synchronous a BBC as cancer diagnosed in both breasts at the same time or within a period of 3 months of diagnosis of the first tumor. One thousand seven hundred and sixty BCT were performed on 1705 patients, 26 of whom presented with BBC. Of these 26 patients, 18 had BCT for both breasts. A higher proportion of patients with BBC showed more tubular carcinoma ( P=0.029) and medially located tumors ( P=0.076) than those with UBC did. The 5- and 10-year local recurrence rates (LRRs) were 4.5% and 9.1%, respectively, in BBC patients, as against 3.3% and 7.6% for UBC after BCT. The 5- and 10-year distant metastasis rates were 26.9% and 50.7%, respectively, for BBC as against 13.4% and 21.1% for UBC after BCT ( P=0.065 and P=0.014, respectively). The 5- and 10-year disease-specific survival (DSS) rates for the 1705 patients were 82.1% and 41%, respectively, after BBC, and 91.4% and 84% after UBC ( P=0.086 and P=0.0045, respectively). Patients with BBC have a higher rate of distant metastasis and a worse DSS than those with UBC. As the LRR is similar for BBC and UBC, BCT is not contraindicated in BBC. The incidence of BBC is low, at 1.5% which makes it difficult to reach any more definitive conclusions on outcome and treatment.

Clinicopathological Features of Hereditary Breast Cancer.

The possible role of germline mutations of BRCA1 and BRCA2 as causative agents of familial breast cancer was assessed. Their possible involvement in the carcinogenesis of hereditary breast cancer was investigated using 63 clinically suspect families. Twenty-one lineages (33.3%) had mutations in one of the two BRCA genes. This relatively low incidence suggested that germline mutations in unknown genes are involved in the carcinogenesis of hereditary breast cancer in the Japanese population. However, the clinicopathological features characteristic of hereditary breast cancer, such as early disease onset, a high incidence of bilateral breast cancer, and a high incidence of multiple primary carcinomas in other organs were confirmed in the present study.

Age at first primary as a determinant of the incidence of bilateral breast cancer

Age at first primary as a determinant of the incidence of bilateral breast cancer

Age at first primary as a determinant of the incidence of bilateral breast cancer. Cumulative and relative risks in a population-based case-control study.

This epidemiologic investigation comprised 1351 of 1423 women in a defined geographic area consecutively diagnosed as having a primary breast cancer. Simultaneous bilateral disease occurred in only 1 patient, whereas a history of previous cancer in the contralateral breast was reported by 65 patients. This prevalence was related to that of 23 previous cases in an age-matched control group of 1351 women from the same population. The relative risk of developing a second primary was 2.9 (95% confidence limit, 1.8-4.6) for the whole material and remained seemingly constant over several decades at a level predetermined by age at first diagnosis, namely 9.9 (95% confidence limit, 3.8-25.8) before the age of 50 and 1.9 (95% confidence limit, 1.1-3.2) after that age. The incidence ratio of bilateral to unilateral disease was used as an estimate of the lifetime risk of developing a second primary in this stable and well-defined population. This calculation revealed cumulative risk figures of 13.3% and 3.5% for women younger and older than 50 years, respectively, at first diagnosis. It was concluded that the occurrence of bilateral disease, which reflects a multicentric neoplastic transformation of the breast epithelium, is a characteristic of early-occurring (premenopausal) disease.