Objective To further elucidate the clinicopathological features, therapy and prognosis of solid papillary carcinoma of breast (SPC). Methods Pathologically confirmed diagnosis of SPC or SPC with invasive carcinoma from Jan 2013 to July 2017 were enrolled in this study. Twenty-seven SPCs were analyzed and were divided into two groups:pure SPC group with 12 patients (44.4%) and SPC combined with associated invasive carcinoma group with 15 patients (55.6%). Then clinical, pathological features including patients' age, present history, tumor size, number of tumor nodules, axillary lymph nodes status and immunohistochemistry results were compared between the two groups. Results Patients' age ranged from 45 to 68 years. Sixteen patients (16/27, 59.3%) had a history of blood nipple discharge. There was no significant difference between patients' age, number of tumor nodules, present history, and axillary lymph nodes status between the two groups (P>0.05). Tumor size ranged from 0.3 cm to 5.5 cm in all patients. There was a significant difference in tumor size between the two groups (P<0.05). Mastectomy and sentinel lymph node biopsy were performed on 16 patients, and mastectomy and axillary lymph nodes excision were performed on 11 patients. Only one patient showed lymph node micrometastasis. All specimens were estrogen receptor (ER) positive and there was no significant difference between the two groups except the Ki-67 expression (P< 0.05). Nineteen (70.4%) patients demonstrated neuroendocrine expression in invasive or in situ tumor foci by detecting synaptophysin, CD56 and chromogranin A, and there was no significant difference between the two groups (P>0.05). The median follow-up was 19.5 months, ranging from 4.5 to 47.5 months, terminated on 31th July 2017. No recurrence or distant metastases occurred. Conclusion SPC usually affects older women with a history of bloody nipple discharge with a favorable prognosis. Lymph node and distant metastases are uncommon. SPC has distinctive pathological features, which need to be distinguished from conventional invasive carcinoma to avoid over-treatment. |