Histo-biological comparative analysis of bilateral breast cancer

Abstract

Bilateral breast cancer occurs in approximately 7% of surviving breast cancer patients. However, a dilemma exists concerning the notion of whether this represents a de novo second primary tumor versus a breast metastasis. We analyzed 81 patients with bilateral breast cancer, 47 (58%) synchronous tumors and 34 (42%) metachronous tumors. Additionally, charts were reviewed for age, family history, full histology data and biological receptors. We found there were no significant differences in concordance between the first and second primary tumors (in both synchronous and metachronous bilateral breast cancer) with respect to histology; grade; T-category; N-category; ER, PR and HER-2 status. In addition, there was no significant difference in the strength of correlation between ER and PR in the first and secondary primary tumors. Our findings suggest that the differentiation of the origin of contralateral breast cancer based on routine histological and biological concordance is inconclusive. Furthermore, the dilemma will continue to exist until additional molecular approaches are applied routinely for research purposes to resolve the debate.

Breast-Conserving Surgery in Bilateral Breast Cancer

“…This finding was also seen in a study by Baker et al where there was no significant difference between the first and second primary tumor in the study's SBC and MBC patients in terms of histologic features and hormonal status. 13 A more recent study by Huo et al 15 found that in the majority of cases, concordance in histological and biological parameters was noted between first and second cancers.…”

“…12 BRCA1 and BRCA2 mutation carriers have an annual risk of 2%–6% of developing a second primary breast cancer. 13 In December 2013, the U.S. Preventive Services Task Force recommended risk assessment, genetic counseling, and genetic testing for BRCA -related cancer in those patients who may have an increased likelihood of a BRCA mutation. In addition to other factors, this included those patients with bilateral breast cancer.…”

Challenges of treating incidental synchronous bilateral breast cancer with differing tumour biology

“…SBBC is a rare entity occurring 0.2–3.2% in many cases but has been reported to be as high as 12% 2 3. Little is known about the rates of SBBC with different hormonal status such as HER2, estrogen receptor (ER) and progesterone receptor (PR), but it is even more infrequent to have bilateral breast cancer with different biological markers, as bilateral tumour biology concordance rates have been found to be between 80% and 100% 2 4 5. Coradini et al 6 had suggested that similar clinical management should be given for bilateral breast cancer and unilateral breast cancer based on these particular concordance rates.…”

Comparative genomic analysis reveals bilateral breast cancers are genetically independent

“…Breast cancer patients have a 2- to 6-fold higher risk of developing contralateral breast cancer than women in the general population have of developing a primary breast cancer [ 1 ]. BBC is presumed to have a unique genetic background, considering that BBC patients are younger, more commonly have a family history and BRCA germline mutations than unilateral breast cancer cases [ 8 , 9 , 37 ]. Only a few reports have presented the genetic findings of sporadic BBCs involving different aspects and factors in breast carcinogenesis [ 17 ].…”

“…First, the biological relationship between the two breast cancers is not well understood. It can be difficult to discriminate between a second primary tumor and a breast metastasis [ 9 ]. Clarifying the issue of BBC clonality has implications for our understanding of breast carcinogenesis and for identifying the optimal breast cancer treatment [ 5 , 6 ], as the management of primary disease and recurrent or metastatic breast cancer is substantially different [ 7 ].…”