Analysis Of Clinicopathological Characteristics And Prognosis Of Primary Metastatic Breast Cancer

Objective:To analyze the clinicopathological characteristics and prognosis of primary metastatic breast cancer (PMBC) by comparing with those of secondary metastatic breast cancer (SMBC).Methods:We collected the data of 156 PMBC patients and 156 SMBC patients treated in Cancer Hospital Chinese Academy of Medical Sciences from January 1st, 2008 to December 31st,2011 retrospectively. The differences of clinical characteristics, pathological diagnosis, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), number and sites of metastasis, treatments and results of follow-up between PMBC group and SMBC group were analyzed using SPSS 21.0.Results:â… . Clinical characteristics:The median age at initial diagnosis of PMBC group was higher than SMBC group (50 years vs.47 years, p=0.003). The second peak of the age curve was presented at 56-60 years old for PMBC group and 51-55 years old for SMBC group. The percentage of premenopausal patients was lower in PMBC group than in SMBC group (48.1% vs.63.5%, p=0.006).â…¡. Pathological characteristics:With regard to pathological type, molecular type and expression of ER, PR and HER2, there were no significant differences between PMBC group and SMBC group. There was a trend of higher histological grade and higher number of lymph node metastasis in PMBC group.â…¢. Metastasis:There were no significant differences about the number of metastases (one site:58.3% vs.59.6%, p=0.818) and the distribution of bone/soft tissue metastasis and visceral metastasis between PMBC group and SMBC group. As for single location of metastasis, though there was higher percentage of bone metastasis in PMBC group (49.4% vs.34.6%, p=0.008), there were no significant differences of single liver, lung, brain or lymph node metastasis between the two groups. In patients with PMBC, bone/soft tissue metastasis was most seen in patients of Luminal A sub-type (52.9%), while visceral metastasis was most seen in patients of HER2 positive sub-type.â…£. Treatment:There were much fewer patients in PMBC group than in SMBC group who received surgery of the primary tumor (55.1% vs.97.4%, p=0.000). Most of the SMBC patients had received systemic therapy before the diagnosis of metastasis (Adjuvant chemotherapy:96.8%, adjuvant endocrine therapy: 50.0%). There was no obvious difference of systemic therapy between the two groups after diagnosis of metastasis, no matter palliative chemotherapy, palliative endocrine therapy, target therapy or the use of bisphosphonates.V. Prognosis:The median survival for patients with PMBC was 44 months (range,2 to 130 months), the 1,3 and 5-year survival rates were 80.8%, 51.3% and 12.8% respectively. The median survival for patients with SMBC was 45 months (range,1 to 125 months), the 1,3 and 5-year survival rates were 78.8%,49.4% and 14.1% respectively. The comparison of survival curves between the two groups showed no significant difference (p=0.858). In multivariable analysis, surgery of primary tumor (p=0.006) and target therapy (p=0.044) were found to correlate with prognosis of PMBC patients. Though surgery of primary tumor was found to improve survival time of PMBC patients significantly, patients with surgery were usually with younger ages, higher KPS status, lower T stages of primary tumors and higher percentages of bone/soft tissue metastasis compared with those without surgery.Conclusion:â… . The age at initial diagnosis of PMBC group was slightly higher than SMBC group. The percentage of premenopausal patients was lower in PMBC group.â…¡. There were no significant differences in clinicopathological characteristics, number of metastases and distribution of sites of metastases between two groups.â…¢. There were much fewer patients in PMBC group than in SMBC group who received surgery of the primary tumor. There was no obvious difference of systemic therapy between two groups after diagnosis of metastasis.IV. There was no obvious difference of metastatic disease survival between two groups.V. Surgery of primary tumor and target therapy correlated with prognosis of PMBC patients. For PMBC patients with favorable factors, surgery of primary tumor may improve survival.