Prognostic factors for skin-involved inflammatory and non-inflammatory breast cancer

Abstract

Objective To analyze the prognostic factors and the role of postmastectomy radiotherapy (PMRT) in skin-involved breast cancer.Methods Fifty-three skin-involved breast cancer patients treated with mastectomy and axillary dissection were retrospectively analyzed.Ten patients had inflammatory breast cancer (IBC).Of the 43 non-inflammatory breast cancer (NIBC) patients, 19(36%) had clinical signs of skin involvement and 24(45%) had pathological skin infiltration without clinical signs.Thirty-three patients (62%) received PMRT with a median dose of 50 Gy, 45 received chemotherapy and 27 received hormone therapy.Results The median follow up time for alive patients was 42 (7 -83) months.The overall 5-year locoregional recurrence (LRR),disease-free survival (DFS) and overall survival (OS) rates were 18%,45% and 64%.Patients with NIBC had a significantly better 5-year DFS (49% vs.30% ,χ2=4.29,P=0.038) and OS (71% vs.37% ,χ2=5.92,P=0.015) than those with IBC.In patients with NIBC, those with primary tumor ≤5 cm had a lower 5-year LRR (11% vs.33% ,χ2= 3.75 ,P =0.053) and a higher 5-year OS (90% vs.38% ,χ2=4.44,P=0.035) as compared to those >5 cm.No significant difference in terms of LRR, DFS or OS was observed between patients with clinical signs of skin involvement and those without.Patients with 0 - 3 positive nodes had an improved 5-year DFS (80% vs.29%, χ2= 6.71, P =0.010) and OS (93% vs.52% ,χ2=6.00,P=0.014) than those with ≥4 positive nodes.Patients with Rec + / Her2 - had a lower5 - year LRR (7 % vs.3 4 % , χ2= 5.70, P= 0.017) and a higher DFS (54% vs.32% ,χ2=8.82 ,P =0.003) than those with triple-negative or Her2 +.There was no significant difference in 5-year LRR (12% vs.30%, χ2= 2.45, P = 0.118) between patients with PMRT and without PMRT.However, the 5-year chest wall recurrence rate was 0% and 50% (χ2= 9.15 ,P =0.002) for patients with chest wall bolus dose > 20 Gy and 20 Gy.Conclusions Skin-involved breast cancer is a heterogeneous group of diseases.Patients with NIBC, small tumor (≤5 cm), less positive nodes (0 -3) or rec +/Her2-have favorable prognosis.Patients with pathologically proven skin involvement without clinical signs have similar prognosis to those with clinical signs.PMRT with chest wall bolus dose >20 Gy is recommended. Key words: Breast neoplasms/radiotherapy; Radiotherapy,postoperation; Skin-involvement; Prognosis