Clinicopathologic features of metastatic small cell carcinoma of the prostate to the liver: a series of four cases

Prognostic Nomogram Predicting Survival and Propensity Score Matching with Demographics and Comparative Analysis of Prostate Small Cell and Large Cell Neuroendocrine Carcinoma

Background: This retrospective study aims to examine the patient demographics, survival rates, and treatment methods for small-cell neuroendocrine carcinoma (SCNEC) and large-cell neuroendocrine carcinoma (LCNEC) of prostate origin while also identifying the main differences between common types of prostate cancer with comparative analysis for survival. Methods: Our analysis utilized the Surveillance, Epidemiology, and End Results database (SEER), and data was collected from 2000-2020. Cox proportional hazards and chi-squared analysis were used for statistical analysis. Results: A total of 718 cases of prostate small and large neuroendocrine carcinoma were identified. The median age was 71.5 years, and the median follow-up was 11.0 years (95% confidence interval (95% CI) = 9.2-12.8). Most patients were over the age of 80 years (33.8%) and Caucasian (74.4%). The overall 5-year survival was 8.0% (95% CI = 6.8-9.2). The 5-year OS for Caucasians was 7.3% (95% C.I. 6.0-8.3). For Black Americans, the 5-year OS was 11.9% (95% C.I. 7.3-16.5). For Hispanics, the 5-year OS was 12.2% (95% C.I. 7.7-16.7). The 5-year cause-specific survival (CSS) was 16.2% (95% CI = 14.3-18.1). For treatment modality, the five-year survival for each were as follows: chemotherapy, 3.5% (95% CI = 2.1-4.9); surgery, 18.2% (95% CI = 13.6-22.8); multimodality therapy (surgery and chemotherapy), 4.8% (95% CI = 1.7-7.9); and combination (chemoradiation with surgery), 5.0% (95% CI = 1.0-9.0). The prognostic nomogram created to predict patient survivability matched the findings from the statistical analysis with a statistical difference found in race, income, housing, stage, and nodal status. The nomogram also indicated a slight increase in mortality with tumors of greater size. This analysis showed a slight increase in mortality for patients of Asian race. In addition, there was a significant increase in death for patients with stage 3 tumors, as well as patients who underwent surgery and radiation. Furthermore, we performed propensity score matching for survival differences, and no survival difference was found between SCNEC and LCNEC. Conclusions: Asian patients, larger tumor size, and distant disease were associated with worse long-term clinical outcomes. By leveraging insights from registry-based studies, clinicians can better strategize treatment options, improving patient outcomes in this challenging oncology arena.

Experience and Lessons Learned in the Treatment of Transforming Small Cell Neuroendocrine Carcinoma of the Prostate: A Case Report and Literature Review

Introduction

Small cell neuroendocrine carcinoma of the prostate (SCNECP) is a rare and highly malignant tumor that commonly transforms into conventional prostate adenocarcinoma (CPAC). Most of SCNECP cases cannot be detected and diagnosed early, and SCNECP is often diagnosed when there is liver and lung metastasis. Therefore, the early detection of the process from CPAC to SCNECP is crucial.

Case Report

We present a case of a 73-year-old man who was initially admitted to our hospital with metastatic CPAC. He was administered goserelin acetate 3.6 mg combined with bicalutamide tablets (50 mg) once daily for endocrine therapy and docetaxel (100 mg) combined with prednisone (5 mg) twice a day. After treatment, the prostate-specific antigen (PSA) level decreased significantly, but the CEA, CA199, and CA125 levels began to increase progressively after a short decline. However, no solid tumor recurrence was observed in multiple reexaminations. It was not until 9 months after the elevation of tumor markers that multiple metastatic lesions appeared in the liver, which finally confirmed the diagnosis of metastatic SCNECP. After chemotherapy with etoposide 360 mg combined with carboplatin 200 mg, the tumor size was significantly reduced, and tumor markers decreased. However, the remission time was only 3 months. The patient's liver metastases continued to grow, and CEA, CA199, and CA125 levels continued to increase.

Conclusion

During CPAC treatment, PSA levels continued to decrease, whereas CEA, CA199, and CA125 levels continued to increase. This suggests the possibility of the transformation of CPAC into SCNECP.

Cancer stem cell in prostate cancer progression, metastasis and therapy resistance

Prostate cancer (PCa) is the most diagnosed malignancy in the men worldwide. Cancer stem cells (CSCs) are the sub-population of cells present in the tumor which possess unique properties of self-renewal and multilineage differentiation thus thought to be major cause of therapy resistance, disease relapse, and mortality in several malignancies including PCa. CSCs have also been shown positive for the common stem cells markers such as ALDH EZH2, OCT4, SOX2, c-MYC, Nanog etc. Therefore, isolation and characterization of CSCs specific markers which may discriminate CSCs and normal stem cells are critical to selectively eliminate CSCs. Rapid advances in the field offers a theoretical explanation for many of the enduring uncertainties encompassing the etiology and an optimism for the identification of new stem-cell targets, development of reliable and efficient therapies in the future. The emerging reports have also provided unprecedented insights into CSCs plasticity, quiescence, renewal, and therapeutic response. In this review, we discuss the identification of PCa stem cells, their unique properties, stemness-driving pathways, new diagnostics, and therapeutic interventions.

Cytomorphology, immunoprofile, and clinicopathologic correlation of metastatic prostatic carcinoma

It may be challenging to diagnose metastatic prostatic carcinoma (PC). This study focused on clinicopathologic correlation, and pitfalls of cytomorphology and immunostains of metastatic PCs. A total of 146 metastatic PCs including 134 (92%) PC without neuroendocrine differentiation-prostatic adenocarcinoma (PAC) and 12 (8%) with neuroendocrine differentiation (PC-NED) were retrieved. Triplicate tissue microarrays (TMA) of 54 surgically excised PCs were constructed for immunostains. Most cases showed Gleason 4 or 5 patterns. Nine percent of cases did not have a prior history of PC and 7% had 2 or more primary malignancies. PAC metastasized more commonly to lymph nodes (49%), and PC-NED metastasized more commonly to liver (58%). Cytologically, metastatic PCs show acini, cribriform, nest, and solid clusters. Most PACs showed conspicuous or prominent nucleoli. PC-NEDs showed typical cytologic features of low-grade or high-grade neuroendocrine neoplasm, or small cell carcinoma features. PACs could be immunoreactive to CDX2 (25%), CK20 (11%), NKX3.1 (99%), PSA (88%), PSAP (78%), and PSMA (92%). PC-NEDs were immunoreactive to neuroendocrine immunomarkers (CD56 [100%], chromogranin [67%], and synaptophysin [100%]) and p63 (25%), and lost expression of prostate-specific markers (NKX3.1, PSA, PSAP, and PSMA). Both PACs and PC-NEDs might be immunoreactive to CK7 (18% versus 33%), GATA3 (4% versus 0%), PAX8 (2% versus 50%, P < .05), and TTF1 (3% versus 57%, P < .05). It is critical to recognize these cytologic features and abbreviation of immunomarkers of metastatic PCs to avoid misinterpretation as metastatic carcinoma from nonprostate organs and inappropriate treatment. In addition, NED may be seen after hormone and chemoradiation treatment.