Complete Response to Chemotherapy against the Recurrence of Neuroendocrine Carcinoma of the Breast in the Anterior Mediastinal Lymph Nodes of a Patient on Hemodialysis: A Case Report

Prognostic factors of primary neuroendocrine breast cancer: A population-based study

Background

Primary neuroendocrine breast carcinomas (NEBCs) are an extremely rare and underrecognized subtype of mammalian carcinoma. The prognostic factors for NEBCs remain controversial.

Methods

In this multicenter retrospective study, the prognostic factors for patients with primary NEBCs who underwent surgery and had a pathologically confirmed diagnosis of neuroendocrine carcinoma in China and the United States were examined. The endpoints were disease‐free survival (DFS) and overall survival (OS).

Results

A total of 51 Chinese patients and 98 US patients were included. In the Chinese cohort, tumor grade and Ki‐67 levels were prognostic factors for DFS in univariate analysis (hazard ratio [HR] = 5.11 [1.67–15.60], p = 0.004; HR = 57.70 [6.36–523.40], p < 0.001, respectively) and multivariate analysis (HR = 100.52 [1.33–7570.21], p = 0.037; HR = 31.47 [1.05–945.82], p = 0.047, respectively). In the US cohort, age was an important prognostic factor for OS in univariate analysis (HR = 1.09 [1.04–1.15], p = 0.001). The random effects model for the combined cohorts revealed age and positive expression of estrogen receptor (ER) as potential prognostic factors for OS (HR = 1.08 [1.01–1.14], p = 0.015; HR = 0.10 [0.02–0.44], p = 0.003, respectively).

Conclusions

Tumor grade and Ki‐67 levels are important prognostic factors for DFS of patients with primary NEBCs. Age and ER status are important prognostic factors for OS of patients with primary NEBCs.

Primary Neuroendocrine Neoplasms of the Breast: Still Open Issues

Neuroendocrine breast tumors represent a rare subtype of breast cancer, accounting for less than 1% of all neuroendocrine neoplasms. Starting from their pathology definition, and going through their prevalence, prognosis and treatment, our knowledge is still really uncertain. In the present short review of the medical literature on this topic, we have evaluated in details their epidemiology, risk factors, pathogenesis, pathology, clinical presentation, radiographic aspects, prognosis, and therapy. We have thus been able to identify a number of open issues regarding primary neuroendocrine neoplasms of the breast that need to be clarified. Our ultimate aim was actually to try to understand whether neuroendocrine neoplasms of the breast can be considered a definite clinical entity and if neuroendocrine differentiation of breast tumors has a really clinical relevance.