Clinicopathologic characteristics and clinical outcomes of pure type and mixed type of tubular carcinoma of the breast: a single-institution cohort study.

Abstract

IntroductionWe aimed to evaluate the clinicopathologic characteristics and clinical outcomes of the mixed type versus the pure type of tubular carcinoma (TC) of the breast in a retrospective cohort study.Materials and methodsPatients were categorized into the following three groups: patients with pure TC of the breast (the PTC group), patients with TC and carcinoma in situ of the breast (the TC-CIS group), and patients with TC and other invasive carcinomas of the breast (the TC-IC group). We compared the clinicopathologic characteristics and treatment outcomes of the three groups. The primary end point of this study was breast cancer-specific survival (BCSS). Secondary end points included distant metastasis-free survival (DMFS) and locoregional recurrence (LRR).ResultsA total of 68 patients were included in this study, including 31 patients in the PTC group, 12 in the TC-CIS group, and 25 in the TC-IC group. Our data showed that PTC and TC-CIS were more likely to be smaller in size (P=0.014) and had substantially less nodal involvement (P=0.019), compared with TC-IC. The median follow-up time was 64.3 months (range, 3.78–223.2 months) for all patients. No locoregional relapse was observed in any group during the follow-up period. The 10-year BCSS of the PTC, TC-CIS, and TC-IC groups was 100%, 100%, and 95.2%, respectively, and the 10-year DMFS was 92.3%, 100%, and 96.0%, respectively. There was no significant difference in terms of BCSS (P=0.53) or DMFS (P=0.84) between the three groups.ConclusionThis study indicates that both the pure type and mixed type of TC of the breast show very low LRR and distant metastasis rate and have excellent survival. The TC-IC group is likely to show good prognosis similar to the PTC group. Further clinical trials with larger sample sizes as well as molecular and genetic studies are warranted.