1702 - Histology of synchronous and metachronous contra-lateral breast carcinoma

Date 28 September 2012
Event ESMO Congress 2012
Session Publication Only
Topics Breast Cancer
Pathology/Molecular Biology
Presenter Zorica Tomasevic
Authors Z. Tomasevic1, Z. Tomasevic1, D. Kolarevic2, Z. Milovanovic3
  • 1Medical Oncology, Institute for Oncology and Radiology, 11000 - Belgrade/YU
  • 2Daily Chmotherapy Hospital, Institute for Oncology and Radiology, 11000 - Belgrade/YU
  • 3Pathology, Institute for Oncology and Radiology, 11000 - Belgrade/YU

Abstract

Background

Contra-lateral breast cancer (CBC) is considered to be the most frequent new malignancy after primary breast cancer (PBC). However, there are few reports about concordance of the histology and other major molecular characteristics between PBC and CBC. Also, to the best of our knowledge, there is no report about CBC histology according to the time of development from PBC.

Aim

To evaluate and compare PBC/CBC histology type according to time of CBC development. Age at CBC and other major molecular characteristics (tumor grade, estrogen/progesterone receptors, HER2) have also been analyzed. Patients and method A cohort of 113 CBC patients, without distant metastases, has been prospectively registered during 28 months. Patients are divided in 2 groups according to the time of CBC diagnose: 1. Synchronous, if the CBC (S-CBC) was diagnosed either simultaneously or within 6 months after PBC; 2. Metachronous (M-CBC) if CBC was diagnosed > 6 months after PBC. (Table 1)

Pts N = 113 Synchronous CBC N = 49 Metachronous CBC N = 64 P
Median age at CBC diagnose (yrs) 57 (33-74) 50 (25-75) 0.007
Median time to CBC (months) 0 (0-≤ 6) 60,5 (0-408) /
PBC-CBC Histology identical (%) 76% 52% 0.006
Lobular/Ductal (%) 41%/59% 41%/59% /

Results

Patient with S-CBC are median 7 years older than patients with M- CBC (p-0.007). S-CBC is more likely to be of the same histological type (76%) than M-CBC (56%) (P- 0.006) In the whole analyzed group, and each subgroup separately, lobular carcinoma is registered in higher percentage (41%) than expected. For all other characteristics (tumor grade, estrogen/progesterone receptors and HER2 status) there was no statistical difference.

Conclusion

According to these results, it seems that patients destined to develop S-CBC or M-CBC, as a first recurrence site, have a greater susceptibility to lobular carcinoma, because this histology type was confirmed in significantly higher percentage than expected. Whether this reflects different genetic susceptibility for S-CBC and M-CBC, and what could be implications on further prognosis, is yet to be analyzed.

Disclosure

All authors have declared no conflicts of interest.