A comprehensive review of incidence and survival in patients with rare histological variants of prostate cancer in the United States from 1973 to 2008

Life expectancy in rare histological prostate cancer subtypes

Survival differences in rare histological prostate cancer (PCa) subtypes relative to age-matched population-based controls are unknown. Within Surveillance, Epidemiology, and End Results database (2004-2020), newly diagnosed (2004-2015) PCa patients were identified. Relying on the Social Security Administration Life Tables (2004-2020) with 5 years of follow-up, age-matched population-based controls (Monte Carlo simulation) were simulated for each patient. Kaplan-Meier analyses addressed survival rates. Of 582,220 patients, 580,368 (99.68%) harbored acinar, 867 (0.15%) ductal, 534 (0.09%) neuroendocrine, 368 (0.07%) mucinous, and 83 (0.01%) signet ring cell carcinoma. The metastatic stage was most prevalent in neuroendocrine (62%). In the localized stage, the overall survival difference at 5 years of follow-up was greatest in neuroendocrine (22% vs. 72%), signet ring cell (78% vs. 84%), and ductal carcinoma (71% vs. 77%). In the locally advanced stage, overall survival difference was greatest in neuroendocrine (16% vs. 79%), signet ring cell (75% vs. 91%), ductal (78% vs. 84%), and mucinous carcinoma (84% vs. 90%). In the metastatic stage, the overall survival difference was greatest in neuroendocrine (3% vs. 81%), mucinous (26% vs. 84%), and acinar carcinoma (27% vs. 85%). Regardless of stage, neuroendocrine carcinoma patients exhibit the least favorable life expectancy compared with population-based controls. Conversely, all other rare histological PCa subtypes do not meaningfully affect life expectancy in localized or locally advanced stages, except for locally advanced signet ring cell adenocarcinoma.

The diagnostic dilemma of squamous differentiation in prostate cancer: A case report

Squamous differentiation in prostate cancer is rare, presenting unique diagnostic and therapeutic challenges. We report a case of high-grade prostatic adenocarcinoma with focal squamous differentiation in a 73-year-old man without prior radiation or androgen deprivation. Immunohistochemistry confirmed the squamous component arose from the adenocarcinoma, not a separate malignancy. This case highlights the importance of morphological assessment and strategic immunohistochemical evaluation to distinguish prostate cancer variants. A biopsy capturing only the squamous component could have led to misdiagnosis and inappropriate treatment. To improve diagnostic accuracy and management, we propose the term 'adenocarcinoma with focal squamous differentiation' over adenosquamous carcinoma.

Baseline Imaging Derived Factors of Response Following [225Ac]Ac-J591 Therapy in Metastatic Castration-Resistant Prostate Cancer: A Lesion Level Analysis

PURPOSE

Actinium-225 labeled prostate-specific membrane antigen (PSMA) targeted radionuclide therapy has emerged as a potential treatment option in the management of men with metastatic castrate-resistant prostate cancer (mCRPC). This study investigated molecular imaging-derived parameters and compared imaging response of lesions categorized by tumor site.

METHODS

Men with mCRPC treated with [225Ac]Ac-J591 from 2017 to 2022 at our center on two prospective trials (NCT03276572 and NCT04506567) with pre- and post-treatment [68Ga]Ga-PSMA-11 Positron Emission Tomography (PET) imaging studies available were included. SUVpeak of the 3 most- and 3 least-avid lesions of the tumor sites were manually assessed. The median change of the SUVpeak from pre- to post-treatment per tumor site was evaluated using the paired Wilcox test. An objective response (OR) in the follow-up image was defined as complete or partial response using PET Response Criteria in Solid Tumors (PERCIST) 1.0.

RESULTS

A total of 46 cases met the criteria for image review; most of them (n = 25, 54.3%) had more than one tumor site category. In total, 445 PSMA PET-positive lesions were assessed: 220 osseous, 163 nodal, 41 visceral, and 21 prostatic lesions. After treatment with [225Ac]Ac-J591, absolute SUVpeak values per tumor site declined significantly (p < 0.05) except for prostatic lesions (p = 1). The PERCIST-OR rate for osseous, nodal, visceral, and prostatic lesions was 53%, 28%, 56%, and 38%, respectively.

CONCLUSION

[225Ac]Ac-J591 is an active treatment in men with mCRPC. Tumor distribution patterns may influence treatment response and potentially prognosis. Our findings warrant further validation in a larger cohort but may be considered in treatment planning and trial design.

Current Status and Challenges in Rare Genitourinary Cancer Research and Future Directions

PURPOSE OF REVIEW

In contemporary urological practice, managing rare genitourinary (GU) malignancies presents significant challenges, necessitating a comprehensive understanding of their unique characteristics and tailored treatment approaches.

RECENT FINDINGS

Rare GU malignancies, whether per se, variants of common histologies, or common tumors in uncommon locations, often lack widely available clinical guidelines. Consequently, treatment decisions are frequently based on empirical evidence, risking suboptimal outcomes. However, recent advances in molecular profiling, targeted therapies, and immunotherapy offer promising avenues for improving management strategies and patient outcomes. This review provides a comprehensive overview of some rare GU malignancies encountered in clinical practice, including their distinct pathological features, current management approaches, and ongoing research directions. Understanding the complexities of these rare tumors and implementing multidisciplinary treatment strategies are essential for optimizing patient care and improving survival outcomes.

Rare histological prostate cancer subtypes: Cancer-specific and other-cause mortality

BACKGROUND

To assess cancer-specific mortality (CSM) and other-cause mortality (OCM) rates in patients with rare histological prostate cancer subtypes.

METHODS

Using the Surveillance, Epidemiology, and End Results database (2004-2020), we applied smoothed cumulative incidence plots and competing risks regression (CRR) models.

RESULTS

Of 827,549 patients, 1510 (0.18%) harbored ductal, 952 (0.12%) neuroendocrine, 462 (0.06%) mucinous, and 95 (0.01%) signet ring cell carcinoma. In the localized stage, five-year CSM vs. OCM rates ranged from 2 vs. 10% in acinar and 3 vs. 8% in mucinous, to 55 vs. 19% in neuroendocrine carcinoma patients. In the locally advanced stage, five-year CSM vs. OCM rates ranged from 5 vs. 6% in acinar, to 14 vs. 16% in ductal, and to 71 vs. 15% in neuroendocrine carcinoma patients. In the metastatic stage, five-year CSM vs. OCM rates ranged from 49 vs. 15% in signet ring cell and 56 vs. 16% in mucinous, to 63 vs. 9% in ductal and 85 vs. 12% in neuroendocrine carcinoma. In multivariable CRR, localized neuroendocrine (HR 3.09), locally advanced neuroendocrine (HR 9.66), locally advanced ductal (HR 2.26), and finally metastatic neuroendocrine carcinoma patients (HR 3.57; all p < 0.001) exhibited higher CSM rates relative to acinar adenocarcinoma patients.

CONCLUSIONS

Compared to acinar adenocarcinoma, patients with neuroendocrine carcinoma of all stages and locally advanced ductal carcinoma exhibit higher CSM rates. Conversely, CSM rates of mucinous and signet ring cell adenocarcinoma do not differ from those of acinar adenocarcinoma.

Systemic metastases in large cell neuroendocrine prostate cancer: a rare case report and literature review

Neuroendocrine prostate neoplasms, encompassing small cell carcinoma, carcinoid, and large cell carcinoma, are infrequently observed in malignant prostate tumors. The occurrence of large cell neuroendocrine prostate cancer (LCNEPC) is exceedingly rare. In this study, the patient initially presented with a persistent dysuria for a duration of one year, accompanied by a serum prostate-specific antigen (PSA) level of 17.83ng/mL. Prostate magnetic resonance imaging (MRI) and chest computed tomography (CT) scan showed that a neoplastic lesion was considered, and prostate biopsy confirmed prostate adenocarcinoma with a Gleason score of 7 (4 + 3). Then, thoracoscopic lung tumor resection was performed, and the pathological examination revealed the presence of primary moderately differentiated invasive adenocarcinoma of the lung and metastatic prostate adenocarcinoma, the Gleason score was 8 (4 + 4). After 1 year of endocrine therapy with goserelin acetate and bicalutamide, he underwent a laparoscopic radical prostatectomy (LRP), the pathological report indicated the presence of adenocarcinoma mixed with NE carcinoma. Two months after the LRP, the patient experienced gross hematuria and sacral tail pain. Further examination revealed multiple metastatic lesions throughout the body. He also underwent transurethral resection of bladder tumor (TURBT) for bladder tumor and received etoposide+ cisplatin chemotherapy three weeks post-surgery. The patient eventually died of multi-organ failure due to myelosuppression after chemotherapy. This case report presents an uncommon instance of LCNEPC with widespread systemic metastases, while also providing a comprehensive review of existing literature to facilitate improved management and treatment strategies for similar patients in subsequent cases.

Cancer stage at diagnosis: Comparison of insurance status in SEER to the Department of Defense Cancer Registry

BACKGROUND

Military individuals, retirees, and their families have free care or minimal out-of-pocket costs in the US military health system (MHS). In contrast, out-of-pocket costs in the US general population vary substantially. This study compared cancer patients with various insurance types in the general population to those in the MHS in cancer stage at diagnosis.

METHODS

Patients were identified from the US Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR) and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program. Tumor stage at diagnosis of breast, prostate, lung, and colon cancers during 2007-2013 was compared between ACTUR and SEER insurance categories of "insured," "insured-no specifics," "any Medicaid," and "uninsured," A multivariable logistic regression analysis estimated the odds ratio (OR) of late stage (Stages III and IV) versus early stage (Stages I and II) cancers comparing SEER insurance status to ACTUR.

RESULTS

There were 18,440 eligible patients identified from ACTUR and 831,959 patients identified from SEER. For all cancer types, patients in the SEER-insured/no specifics, Medicaid, and uninsured groups had significantly greater likelihood of late stage diagnosis compared to ACTUR patients. The adjusted ORs were greatest among uninsured and Medicaid patients. The SEER-insured group also had a significantly higher odds of advanced stage disease than ACTUR patients for prostate cancer and lung cancer.

CONCLUSION

Patients in the MHS with universal access to healthcare were diagnosed at an earlier stage than those in the general population. This difference was most evident compared to Medicaid and uninsured groups.

PET radiotracers for whole-body in vivo molecular imaging of prostatic neuroendocrine malignancies

Prostatic neuroendocrine malignancies represent a spectrum of diseases. Treatment-induced neuroendocrine differentiation (tiNED) in hormonally treated adenocarcinoma has been the subject of a large amount of recent research. However, the identification of neuroendocrine features in treatment-naïve prostatic tumor raises a differential diagnosis between prostatic adenocarcinoma with de novo neuroendocrine differentiation (dNED) versus one of the primary prostatic neuroendocrine tumors (P-NETs) and carcinomas (P-NECs). While [18F]FDG is being used as the main PET radiotracer in oncologic imaging and reflects cellular glucose metabolism, other molecules labeled with positron-emitting isotopes, mainly somatostatin-analogues labeled with 68Ga and prostate-specific membrane antigen (PSMA)-ligands labeled with either 18F or 68Ga, are now routinely used in departments of nuclear medicine and molecular imaging, and may be advantageous in imaging prostatic neuroendocrine malignancies. Still, the selection of the preferred PET radiotracer in such cases might be challenging. In the current review, we summarize and discuss published data on these different entities from clinical, biological, and molecular imaging standpoints. Specifically, we review the roles that [18F]FDG, radiolabeled somatostatin-analogues, and radiolabeled PSMA-ligands play in these entities in order to provide the reader with practical recommendations regarding the preferred PET radiotracers for imaging each entity. In cases of tiNED, we conclude that PSMA expression may be low and that [18F]FDG or radiolabeled somatostatin-analogues should be preferred for imaging. In cases of prostatic adenocarcinoma with dNED, we present data that support the superiority of radiolabeled PSMA-ligands. In cases of primary neuroendocrine malignancies, the use of [18F]FDG for imaging high-grade P-NECs and radiolabeled somatostatin-analogues for imaging well-differentiated P-NETs is recommended. KEY POINTS: • The preferred PET radiotracer for imaging prostatic neuroendocrine malignancies depends on the specific clinical scenario and pathologic data. • When neuroendocrine features result from hormonal therapy for prostate cancer, PET-CT should be performed with [18F]FDG or radiolabeled somatostatin-analogue rather than with radiolabeled PSMA-ligand. • When neuroendocrine features are evident in newly diagnosed prostate cancer, differentiating adenocarcinoma from primary neuroendocrine malignancy is challenging but crucial for selection of PET radiotracer and for clinical management.

Impact of Epithelial Histological Types, Subtypes, and Growth Patterns on Oncological Outcomes for Patients with Nonmetastatic Prostate Cancer Treated with Curative Intent: A Systematic Review

CONTEXT

The optimal management for men with prostate cancer (PCa) with unconventional histology (UH) is unknown. The outcome for these cancers might be worse than for conventional PCa and so different approaches may be needed.

OBJECTIVE

To compare oncological outcomes for conventional and UH PCa in men with localized disease treated with curative intent.

EVIDENCE ACQUISITION

A systematic review adhering to the Referred Reporting Items for Systematic Reviews and Meta-Analyses was prospectively registered on PROSPERO (CRD42022296013) was performed in July 2021.

EVIDENCE SYNTHESIS

We screened 3651 manuscripts and identified 46 eligible studies (reporting on 1 871 814 men with conventional PCa and 6929 men with 10 different PCa UHs). Extraprostatic extension and lymph node metastases, but not positive margin rates, were more common with UH PCa than with conventional tumors. PCa cases with cribriform pattern, intraductal carcinoma, or ductal adenocarcinoma had higher rates of biochemical recurrence and metastases after radical prostatectomy than for conventional PCa cases. Lower cancer-specific survival rates were observed for mixed cribriform/intraductal and cribriform PCa. By contrast, pathological findings and oncological outcomes for mucinous and prostatic intraepithelial neoplasia (PIN)-like PCa were similar to those for conventional PCa. Limitations of this review include low-quality studies, a risk of reporting bias, and a scarcity of studies that included radiotherapy.

CONCLUSIONS

Intraductal, cribriform, and ductal UHs may have worse oncological outcomes than for conventional and mucinous or PIN-like PCa. Alternative treatment approaches need to be evaluated in men with these cancers.

PATIENT SUMMARY

We reviewed the literature to explore whether prostate cancers with unconventional growth patterns behave differently to conventional prostate cancers. We found that some unconventional growth patterns have worse outcomes, so we need to investigate if they need different treatments. Urologists should be aware of these growth patterns and their clinical impact.

Prostate Volume Influence on Postoperative Outcomes for Patients Undergoing RARP: A Monocentric Serial Analysis of 500 Cases

Elevated prostate volume is considered to negatively influence postoperative outcomes after robot-assisted radical prostatectomy (RARP). We aim to investigate the influence of prostate volume on readmissions and complications after RARP. Methods: A total of 500 consecutive patients who underwent RARP between April 2019 and August 2022 were included. Patients were dichotomized into two groups using a prostate volume cut-off of 50 mL (small and normal prostate (SNP) n = 314, 62.8%; large prostate n = 186, 37.2%). Demographic, baseline, and perioperative data were analyzed. The postoperative complications and readmission rates within 90 days after RARP were compared between groups. A univariate linear analysis was performed to investigate the association between prostate volume and other relevant outcomes. Results: Patients with larger prostates had a higher IPSS score, and therefore, more relevant LUTS at the baseline. They had higher ASA scores (p = 0.015). They also had more catheter days (mean 6.6 days for SNP vs. 7.5 days for LP) (p = 0.041). All oncological outcomes were similar between the groups. Although statistical analysis showed no significant difference between the groups (p = 0.062), a trend for minor complications in patients with larger prostates, n = 37/186 (19.8%) for the LP group vs. n = 37/314 (11.7%) in the SNP group, was observed. Namely, acute urinary retention and secondary anastomosis insufficiency. Major complications with an SNP (4.4%) and LP (3.7%) (p = 0.708) and readmissions with an SNP (6.25%) and LP (4.2%) (p = 0.814) were infrequent and distributed equally between the groups. In univariate analysis, prostate volume could solely predict a longer console time (p = 0.005). Conclusions: A higher prostate volume appears to have minimal influence on the perioperative course after RARP. It can prolong catheter days and increase the incidence of minor complications such as acute urinary retention. However, it might predict minor changes in operating time. Yet, prostate volume has less influence on major complications, readmissions, or oncological results.

Addressing the need for more therapeutic options in neuroendocrine prostate cancer

INTRODUCTION

Neuroendocrine prostate cancer (NEPC) is an aggressive form of prostate cancer frequently seen after prolonged treatment of castration resistant prostate cancer (CRPC). NEPC has become increasingly prevalent over the last 20 years, with a poor prognosis caused by a late diagnosis and limited treatment options. Recent advances in PET/CT imaging and targeted radioimmunotherapy are promising, but more research into additional treatment options is needed.

AREAS COVERED

The aim of this review is to analyze the current imaging and treatment options for NEPC, and to highlight future potential treatment strategies. A Pubmed search for 'Neuroendocrine Prostate Cancer' was performed and relevant articles were reviewed.

EXPERT OPINION

The recent FDA approval and success of 177 PSMA Lutetium in CRPC is promising, as 177 Lutetium could potentially be paired with a NEPC specific biomarker for targeted therapy. Recent laboratory studies pairing DLL3, which is overexpressed in NEPC, with 177 Lutetium and new PET agents have showed good efficacy in identifying and treating NEPC. The success of future development of NEPC therapies may depend on the availability of 177 Lutetium, as current supplies are limited. Further research into additional imaging and treatment options for NEPC is warranted.

Radiotherapy for ductal carcinoma of the prostate: an analysis based on the Japanese radiation oncology study group survey

BACKGROUND

The clinical characteristics of prostate ductal carcinoma is still unclear, and treatment strategy has not yet been established due to its rarity. Therefore, we conducted a multicenter survey of radiation therapy for prostate ductal carcinoma in Japan.

METHOD

Data of patients with ductal carcinoma of the prostate treated with radiation therapy between 1996 and 2018 were extracted from the database of each facility.

RESULTS

Fifty-two treatment records of 41 patients were collected from nine institutions. The treatment purpose and situations were varied curative intent to palliation. Twenty-eight patients received curative treatments. The median follow-up period of these patients was 68 months. Androgen deprivation therapy was combined with radiation therapy in 26 cases (93%). X-ray and particle irradiation was used. Radiation dose range was 63-78 Gy; 5-year overall survival, progression-free survival and biochemical relapse-free survival were 87.0, 79.3 and 79.3%, respectively. One patient experienced Grade 3 radiation proctitis and one experienced Grade 3 radiation cystitis. There were no Grade 4 or worse adverse events.

CONCLUSION

Most patient received similar treatment with adenocarcinoma of prostate, and the clinical results were compatible. For more reliable evidence, further studies are required.

Management about intravesical histological transformation of prostatic mucinous carcinoma after radical prostatectomy: A case report

BACKGROUND

Prostatic mucinous carcinoma (MC) and prostatic signet ring cell carcinoma are two variants of prostate cancer. MC has a higher overall survival time among all variants, while signet ring cell carcinoma is associated with lower survival time relative to other carcinomas. Only a small proportion of prostatic MC may contain signet ring cells. Over the last several decades there were only 12 patients that were documented in two studies.

CASE SUMMARY

We report on a 64-year-old man who was diagnosed with prostatic MC after he received a robotic-assisted laparoscopic radical prostatectomy in the West China Hospital. After robotic-assisted laparoscopic radical prostatectomy, the patient underwent three successive transurethral resections of bladder tumors. Pathological examination of the first transurethral resection of bladder tumors specimen indicated that the neoplasm was prostatic MC that had metastasized to the urinary bladder. The subsequent two transurethral resections of bladder tumors indicated the presence of prostatic mucinous carcinoma with signet ring cells.

CONCLUSION

This case report aimed to share the management experience, raise awareness, and highlight the importance of multidisciplinary cooperation of prostatic mucinous carcinoma with signet ring cells.

Male Breast Metastasis: A Case of Treatment-Emergent Neuroendocrine Prostate Cancer

Treatment-emergent transformed neuroendocrine prostate cancer (NEPC) is a highly aggressive type of prostate cancer that may arise from typical adenocarcinoma of the prostate, which is associated with rapidly progressive disease involving visceral sites and refractoriness to hormonal therapy.

We present the case of a 74-year old male with a known history of stable prostate adenocarcinoma treated with transurethral prostate resection, local radiotherapy (RT), and androgen deprivation therapy (ADT) in 2020 who presented to the emergency room with complaints of shoulder and anterior chest pain, dyspnoea, and fatigue. Upon examination, a solid, adherent breast mass and infra-clavicular adenopathy were palpable. Thoracic computed tomography (CT) scan showed adenopathies in multiple thoracic chains, bilateral pulmonary nodular opacities, multiple osteolytic lesions, and bilateral enlargement of retro areolar tissue. A staging CT scan revealed further hepatic and penile lesions. Breast mass biopsy was compatible with small cell neuroendocrine cancer. Biopsies of the prostate, penis, lymph nodes, and bronchus were also performed. Histology of the prostate showed focal infiltration by the known adenocarcinoma while all others documented extensive infiltration by neuroendocrine carcinoma, whose morphology and immunohistochemical profile were identical to that of the breast.

This case highlights the challenges a diagnosis of neuroendocrine prostate cancer might pose, and the aggressiveness of this type of cancer, which frequently presents with advanced disease and is associated with poor outcomes.

Can Diet Prevent Urological Cancers? An Update on Carotenoids as Chemopreventive Agents

Urological cancers, namely prostate, bladder, kidney, testicular, and penile cancers, are common conditions that constitute almost one-quarter of all malignant diseases in men. Urological cancers tend to affect older individuals, and their development is influenced by modifiable metabolic, behavioral, and environmental risk factors. Phytochemicals may have cancer-fighting properties and protect against cancer development, slow its spread, and reduce the risk of cancer deaths in humans. This paper aims to review the current literature in regard to the effects of carotenoids in reducing urological cancer risk.

Anaplastic Features in Advanced Prostate Cancer With and Without DNA Damage Repair Mutations

BACKGROUND

Anaplastic prostate cancer has a poor prognosis with limited treatment options. Seven clinical features of anaplastic prostate cancer have been prospectively identified. In this phase II clinical trial, we identified mutations, including DNA damage repair (DDR) mutations, in patients with metastatic castration-resistant prostate cancer (mCRPC) who were treated with durvalumab and olaparib and determined how many of them can be described as anaplastic, and we examined the overlap between anaplastic features and DDR mutations.

METHODS

Eligible patients with mCRPC received prior enzalutamide, abiraterone, or both. Patients were treated with durvalumab 1500 mg i.v. every 28 days and olaparib 300 mg p.o. every 12 hours until disease progression or unacceptable toxicity. Patients underwent mandatory baseline biopsies of metastatic lesions.

RESULTS

Baseline characteristics were similar between anaplastic and nonanaplastic patients. Eleven patients (20%) displayed clear anaplastic features, and 43 (78.2%) lacked anaplastic features. In the anaplastic group, 2/11 (18.2%) had germline DRR mutations, and 4/11 (36.3%) had somatic DDR mutations. In the nonanaplastic group, 7/43 (16.3%) had germline mutations, and 13/43 (30.2%) had somatic mutations. Median progression-free survival (PFS) times in patients with anaplastic features (6.5 months) and without anaplastic features (5.1 months) were similar (hazard ratio 0.998, P = .996).

CONCLUSIONS

Patients with and without anaplastic features appear to have similar total rates of DDR mutations and also similar rates of somatic and germline DDR mutations. Patients with anaplastic features have a trend toward improved PFS when treated with olaparib and durvalumab compared with nonanaplastic patients.

Narrative review of challenges in the management of advanced neuroendocrine prostate cancer

With wide availability of potent androgen receptor targeted agents (ARTAs), the incidence of treatment-related neuroendocrine prostate cancer (t-NEPC) has been dramatically increasing. However, there is no standard effective treatment for this disease state. Recent advances in genomic and molecular medicine have identified some critical features of NEPC that would help in understanding the biology of the disease. Furthermore, invaluable pre-clinical in vivo and in vitro research models that represent NEPC have been developed. These advances in research have revealed a large heterogeneity of t-NEPC with varying degree of androgen receptor (AR), neuroendocrine (NE) marker, and cell cycle associated gene expressions, which may have clinical implication in terms of prognosis and treatment selection. Based on these studies, some potential drug targets have been identified, and early clinical trials are ongoing. In the future, more precise disease classification and biomarker-driven selection of patients will be critical for optimization of treatment for patients with NEPC. In the present review, we describe up-to-date findings of recent research on this topic and introduce ongoing therapeutic developments that are expected to lead to novel treatment strategies for NEPC in the future.

Genomic analysis of circulating tumor cells in adenosquamous carcinoma of the prostate: a case report

BACKGROUND

Adenosquamous carcinoma of the prostate (ASCP) is an extremely rare and aggressive prostate cancer variant, whose genomic characteristics have not been elucidated. Although liquid biopsy of circulating tumor cells (CTCs) is an emerging topic in oncology, no study has assessed CTCs in patients with ASCP.

CASE PRESENTATION

A 76-year-old man presented with discomfort in his urethra. His prostate-specific antigen (PSA) level was 13.37 ng/mL. A computed tomography (CT) scan indicated a prostate mass with multiple lymph node and lung metastases. The patient underwent transurethral resection of the prostate and prostatic needle biopsy; both specimens demonstrated Gleason grade group 5 acinar adenocarcinoma of the prostate. Bone scintigraphy indicated bone metastasis in the ischium. Combined androgen blockade was implemented, and his serum PSA level rapidly decreased to 0.01 ng/mL. However, a CT scan 6 months after the initial diagnosis revealed worsening of the disease. The patient therefore underwent repeated prostatic needle biopsy; its specimen demonstrated prostatic adenocarcinoma together with squamous carcinoma components. As immunohistochemical analyses showed the tumor cells to be negative for CD56, chromogranin A, synaptophysin, and PSA, the definitive diagnosis was ASCP. Although the patient underwent chemotherapy (docetaxel and cabazitaxel), he died of the disease 3 months after the diagnosis of ASCP, or 13 months after the initial diagnosis of prostatic adenocarcinoma. His PSA values remained ≤ 0.2 ng/mL. CTCs from the patient's blood (collected before starting docetaxel) were analyzed and genomically assessed. It showed 5 cytokeratin (CK)+ CTCs, 14 CK- CTCs, and 8 CTC clusters, per 10 mL. Next-generation sequencing identified a total of 14 mutations in 8 oncogenes or tumor suppressor genes: PIK3CB, APC, CDKN2A, PTEN, BRCA2, RB1, TP53, and CDK12. Of 14 mutations, 9 (64%) were detected on CK- CTCs and 5 (36%) were detected on CK+ CTCs.

CONCLUSIONS

This is the first report of CTC analysis and genomic assessment in ASCP. Although the prognosis of ASCP is dismal due to lack of effective treatment, genomic analysis of CTCs might lead to effective treatment options and improved survival.

Oncological outcomes of patients with ductal adenocarcinoma of the prostate receiving radical prostatectomy or radiotherapy

Objective

To evaluate the oncological outcomes of ductal adenocarcinoma of the prostate (DAC) managed with radical prostatectomy (RP) or radiotherapy (RT) and optimize the proper treatment modality to DAC comprehensively.

Methods

The cohorts included a total of 528 patients from the Surveillance, Epidemiology and End Results (SEER) database, 354 receiving RP and 174 receiving RT. Cox proportional hazards regressions were performed to assess cancer specific mortality (CSM) and overall mortality (OM) between treatment groups. A competing risk analysis was further conducted. Subgroup analyses by age and level of prostate-specific antigen (PSA) were performed. Propensity score matching was implemented.

Results

Patients managed with RP had lower risks of CSM and OM compared with RT (before matching: Hazard ratio [HR]=0.24, 95% confidence interval [CI] 0.13–0.47 and HR=0.26, 95% CI 0.17–0.40, respectively; after matching: HR=0.18, 95% CI 0.04–0.82 and HR=0.28, 95% CI 0.11–0.70, accordingly). Subgroup analyses demonstrated that patients in the middle tertile of the age or with lower tertile PSA level managed with RP took lower risks of OM significantly (HR=0.18, 95% CI 0.06–0.57, p<0.01 and HR=0.17, 95% CI 0.06–0.54, p<0.01).

Conclusion

Among patients with DAC, treatment with RP was associated with better survival outcomes in comparison with RT. Patients with DAC in the middle tertile of the age and with lower tertile PSA level benefited the most from RP.

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

BACKGROUND

Small cell neuroendocrine carcinoma of the prostate (SCNECP) is a rare, aggressive subtype of prostate carcinoma. Most SCNECP arise from conventional prostate adenocarcinoma (CPAC) treated with androgen deprivation therapy (ADT).

CASE PRESENTATIONS

We identified four cases of CPAC treated with ADT, which evolved to SCNECP with liver metastasis. The average interval between the diagnosis of CPAC and SCNECP was 102 months (range: 12 to 168). Histologically, the tumors showed nests of cells with high nuclear:cytoplasmic ratios, granular chromatin, and frequent mitoses. All cases were synaptophysin, chromogranin, and AE1/AE3 positive, with a Ki-67 labeling index ≥70%. NKX3.1 was negative in all but one case and TTF-1 was positive in half. Weak ERG positivity by IHC was seen in one case which also demonstrated the TMPRSS2-ERG gene rearrangement; all other cases were negative for ERG by IHC. Serum prostate specific antigen (PSA) levels were normal to near-normal in all. The median interval between the diagnosis of SCNECP and death was 3.25 months (range: 0.75 to 26).

CONCLUSIONS

Our case series highlights the importance of considering a prostate primary, even in the setting of normal PSA levels and loss of prostate markers, when diagnosing neuroendocrine carcinoma in the liver. Further, we emphasize the significance of diagnosing SCNECP that metastasizes to the liver, as it portends a particularly dismal prognosis.

Clinicopathological characteristics and survival outcomes in neuroendocrine prostate cancer: A population-based study

OBJECTIVE

This study aimed to investigate the clinicopathological features and the survival outcomes of neuroendocrine prostate cancer (NEPC).

METHODS

Within the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute, we identified a total of 510 patients with NEPC between 2006 and 2015. Age-adjusted incidence rates were evaluated in the study by the SEER∗Stat Software version 8.3.6. Kaplan-Meier analysed assessed overall survival (OS) after stratification according to marital status, age, histologic subtype, metastatic status, and treatment. The significant differences were assessed in a log-rank test. Univariate and multivariate cox hazard regression analysis were performed to determine independent predictors of OS.

RESULTS

From a total of 560,124 patients with prostate cancer diagnosed between 2006 and 2015, we identified 510 cases of de novo NEPC. Regarding histology, among all the NEPC, 329 (64.5%) patients were diagnosed as small cell carcinoma, 181 (39.8%) were nonsmall cell carcinoma. The overall age-adjusted incidence of NEPC statistically significantly increased from 0.321/1,000,000 person-years in 2006 to 0.587/1,000,000 person-years in 2015. The median OS in our study cohort was 9 months (95% CI, 8-10 months). Multivariate cox regression analysis showed that age, histologic subtype, and stage were independent prognostic factors for NEPC patients. The majority of NEPC (78.2%) were metastatic at diagnosis. In terms of treatment, for metastatic tumor patients, chemotherapy was the most effective therapy. Chemotherapy increased the OS of patients with regional (distant) metastases from 8 months (5 months) to 13.5 months (9 months).

CONCLUSION

NEPC is extremely rare but the incidence of NEPC has been increasing in the past years. The prognosis of NEPC is poor because most cases are diagnosed at metastatic stage. The patients with metastases are typically treated with chemotherapy and chemotherapy shows survival benefits in both regional and distant metastatic tumor patients.

Neuroendocrine Carcinoma as an Independent Prognostic Factor for Patients With Prostate Cancer: A Population-Based Study

BACKGROUND

Neuroendocrine carcinoma (NEC) is a rare and highly malignant variation of prostate adenocarcinoma. We aimed to investigate the prognostic value of NEC in prostate cancer.

METHODS

A total of 530440 patients of prostate cancer, including neuroendocrine prostate cancer (NEPC) and adenocarcinoma from 2004 to 2018 were obtained from the national Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM), multivariable Cox proportional hazard model, Kaplan-Meier method and subgroup analysis were performed in our study.

RESULTS

NEPC patients were inclined to be older at diagnosis (Median age, 69(61-77) vs. 65(59-72), P< 0.001) and had higher rates of muscle invasive disease (30.9% vs. 9.2%, P < 0.001), lymph node metastasis (32.2% vs. 2.2%, P < 0.001), and distal metastasis (45.7% vs. 3.6%, P < 0.001) compared with prostate adenocarcinoma patients. However, the proportion of NEPC patients with PSA levels higher than 4.0 ng/mL was significantly less than adenocarcinoma patients (47.3% vs. 72.9%, P<0.001). NEPC patients had a lower rate of receiving surgery treatment (28.8% vs. 43.9%, P<0.001), but they had an obviously higher rate of receiving chemotherapy (57.9% vs. 1.0%, P<0.001). A Cox regression analysis demonstrated that the NEPC patients faced a remarkably worse OS (HR = 2.78, 95% CI = 2.34-3.31, P < 0.001) and CSS (HR = 3.07, 95% CI = 2.55-3.71, P < 0.001) compared with adenocarcinoma patients after PSM. Subgroup analyses further suggested that NEPC patients obtained significantly poorer prognosis across nearly all subgroups.

CONCLUSION

The prognosis of NEPC was worse than that of adenocarcinoma among patients with prostate cancer. The histological subtype of NEC is an independent prognostic factor for patients with prostate cancer.

Analysis of Prostate Adenocarcinoma Histopathological Types in Relation to Tumor Grade

Prostate adenocarcinomas are some of the most common malignancies diagnosed in men, and the evaluation of tumor growth patterns is the basis for establishing the aggressiveness of the lesions. The study included 283 cases of prostate adenocarcinomas for which histopathological type and tumor grade were analyzed. The results indicated the association of ductal, sarcomatoid and signet ring-like cell types with aggressive growth patterns and high scores, atrophic and pseudohyperplastic types with mild growth patterns and low scores, foamy gland type presented intermediate growth patterns/scores, while conventional and colloid types had variable aspects. The grading systems used may be considered consistent with the histological types of prostate adenocarcinomas.

Impact of treatment modality on overall survival in localized ductal prostate adenocarcinoma: A national cancer database analysis

PURPOSE

Ductal adenocarcinoma is considered a rare histological variant of prostate adenocarcinoma (PCa). Given the rarity of this subtype, optimal treatment strategies for men with nonmetastatic ductal PCa is largely unknown. We aimed to describe the impact of surgery, radiotherapy, systemic therapy, and observation on overall survival (OS) in men with nonmetastatic ductal PCa.

MATERIALS AND METHODS

We selected 1,656 cases of nonmetastatic ductal PCa, diagnosed between 2004 and 2015, within the National Cancer Database. Covariates included age, race, Charlson comorbidity score, clinical T stage, clinical lymph node stage, serum prostate specific antigen (PSA), income, hospital type, insurance status, year of diagnosis, and location of residence. Cox regression analysis tested the impact of treatment (surgery, radiotherapy, systemic therapy, and observation) on OS.

RESULTS

In men with nonmetastatic ductal PCa, median (interquartile range [IQR]) age and PSA were 67 (60-73) years and 6.2 (4.2-10.7) ng/ml, respectively. Advanced local stage (≥cT3a) was most frequently observed in patients initially treated with systemic therapy (34.8%), followed by those treated with radiotherapy (18.1%), surgery (7.1%) and observation (6.4%, P< 0.001). Serum PSA at presentation was highest in the systemic therapy cohort (median 16.0 ng/ml, IQR: 4.9-37.7), followed by the radiotherapy cohort (median 7.2 ng/ml, IQR: 4.1-12.2), observation cohort (median 7.0 ng/ml, IQR: 4.3-13.3) and surgery cohort (median 5.9 ng/ml, IQR: 4.3-9.2, P< 0.001). Multivariable analysis showed that in comparison to men treated surgically, OS was significantly lower for patients receiving radiotherapy (HR 2.2; 95% CI: 1.5-3.2), under observation (HR 4.6; 95% CI: 2.8-7.6) and receiving systemic therapy (HR 5.2; 95% CI: 3.0-9.1) as an initial course of treatment.

CONCLUSIONS

While limited by its retrospective nature, our study shows that starting treatment with surgery is associated with more favorable long-term OS outcomes than radiotherapy, systemic therapy or observation.

Ranking Series of Cancer-Related Gene Expression Data by Means of the Superposing Significant Interaction Rules Method

The Superposing Significant Interaction Rules (SSIR) method is a combinatorial procedure that deals with symbolic descriptors of samples. It is able to rank the series of samples when those items are classified into two classes. The method selects preferential descriptors and, with them, generates rules that make up the rank by means of a simple voting procedure. Here, two application examples are provided. In both cases, binary or multilevel strings encoding gene expressions are considered as descriptors. It is shown how the SSIR procedure is useful for ranking the series of patient transcription data to diagnose two types of cancer (leukemia and prostate cancer) obtaining Area Under Receiver Operating Characteristic (AU-ROC) values of 0.95 (leukemia prediction) and 0.80-0.90 (prostate). The preferential selected descriptors here are specific gene expressions, and this is potentially useful to point to possible key genes.

Neuron-specific enolase has potential value as a biomarker for [18F]FDG/[68Ga]Ga-PSMA-11 PET mismatch findings in advanced mCRPC patients

BACKGROUND

PSMA-targeted radioligand therapy (PSMA-RLT) yielded impressive results in the metastasized castration-resistant prostate carcinoma (mCRPC) setting. High expression of PSMA is essential for successful PSMA-RLT. However, some patients develop [18F]FDG-avid lesions with low or no PSMA expression ([18F]FDG/[68Ga]Ga-PSMA-11 mismatch findings on PET/CT) in the course of treatment. Those lesions are not affected by PSMA-RLT and a change in therapy management is needed. To enable early mismatch detection, possible blood parameters as indicators for the occurrence of [18F]FDG/[68Ga]Ga-PSMA-11 mismatch findings on PET/CT were evaluated.

METHODS

Retrospective study of N = 66 advanced mCRPC patients with dual [68Ga]Ga-PSMA-11 and [18F]FDG PET/CT imaging within 4 weeks, who were referred for or received [177Lu]Lu-PSMA-617 radioligand therapy. Prostate-specific antigen (PSA), neuron-specific enolase (NSE), gamma-glutamyltransferase (GGT), and alkaline phosphatase (ALP) were tested as indicators for the occurrence of [18F]FDG/[68Ga]Ga-PSMA-11 mismatch findings. Additional to absolute values, relative changes (ΔPSA, ΔNSE, ΔGGT, ΔALP) over a period of 4 ± 1 weeks prior to [18F]FDG PET/CT were analyzed.

RESULTS

In total, 41/66 (62%) patients revealed at least one [18F]FDG/[68Ga]Ga-PSMA-11 mismatch finding on PET/CT. These mismatch findings were detected in 13/41 (32%) patients by screening for and in 28/41 (68%) patients during PSMA-RLT. NSE serum level (55.4 ± 44.6 μg/l vs. 18.5 ± 8 μg/l, p < 0.001) and ΔNSE (93.8 ± 124.5% vs. 2.9 ± 39.5%, p < 0.001) were significantly higher in the mismatch group than in the non-mismatch group. No significant differences were found for serum PSA (p = 0.424), ΔPSA (p = 0.417), serum ALP (p = 0.937), ΔALP (p = 0.611), serum GGT (p = 0.773), and ΔGGT (p = 0.971). For NSE and ΔNSE, the maximum value of the Youden index in ROC analysis was at a cut-off level of 26.8 μg/l (sensitivity 78%, specificity 96%) and at + 13.9% (sensitivity 84%, specificity 75%), respectively. An introduced scoring system of both parameters achieved a sensitivity of 90% and a specificity of 88% for the occurrence of [18F]FDG/[68Ga]Ga-PSMA-11 mismatch.

CONCLUSION

We observed a significantly higher absolute serum concentration and a higher relative increase of NSE in advanced mCRPC patients with [18F]FDG-avid and insufficient PSMA expressing metastases ([18F]FDG/[68Ga]Ga-PSMA-11 mismatch findings on PET/CT) in our cohort. NSE might be used as a potential laboratory indicator for [18F]FDG/[68Ga]Ga-PSMA-11 mismatch findings, if this observation is confirmed in future, ideally prospective, studies in larger patient cohorts.

Mucinous Prostate Cancer Shows Similar Prognosis to Typical Prostate Acinar Carcinoma: A Large Population-Based and Propensity Score-Matched Study

Background: Mucinous prostate cancer (PCa) is an extremely rare form of prostate malignancy. To date, the limited knowledge of its biology and outcomes stems from mostly small, single institution experiences. We analyzed the Surveillance, Epidemiology, and End Results (SEER) database to explore the incidence and treatment of mucinous PCa together with its prognostic factors to gain relatively large and consolidated insights. Methods: Age-adjusted incidence (AAI) rates were evaluated over time. Propensity score matching (PSM) and Kaplan-Meier analyses were used to compare the prognosis between mucinous PCa and typical prostate acinar adenocarcinoma. We assessed cancer-specific survival (CSS) and overall survival (OS) after patient stratification according to summary stage and treatment choice. Cox hazards regression analysis was performed to determine independent predictors of CSS and OS. Results: The AAI in 2016 was 0.24 per million. Patients with mucinous PCa had similar CSS and OS to matched individuals with typical prostate acinar adenocarcinoma. In terms of treatment, 65.3% of mucinous PCa patients underwent surgery, and 23.9% received radiation therapy. Patients who underwent surgery had longer survival (CSS, p = 0.012; OS, p < 0.001), and patients who received radiation therapy had similar survival to those who did not receive radiation therapy (CSS, p = 0.794; OS, p = 0.097). A multivariate Cox analysis for CSS and OS showed that older age (CSS: HR: 4.982, p = 0.001; OS: HR: 4.258, p < 0.001) and distant stage (CSS: HR: 40.224, p < 0.001; OS: HR: 9.866, p < 0.001) were independent prognostic factors for mucinous PCa patients. Conclusions: Mucinous PCa has an extremely low AAI. Analysis of its outcomes indicates that it is not a more malignant tumor as previously suspected. Mucinous PCa shows a similar prognosis to typical prostate acinar carcinoma. Surgery was associated with prolonged survival. An older age at diagnosis and distant stage was associated with poor survival.

Case report: Adenosquamous carcinoma of the prostate with greater than 20 month response to multimodal therapy

Adenosquamous carcinoma is an extremely rare and lethal subtype of prostate cancer affecting an estimated 0.03 per million men annually. It has been associated with prior hormone therapy for prostate adenocarcinoma. We present a case of de novo adenosquamous carcinoma of the prostate treated with a multimodal approach including surgery, androgen-deprivation therapy, chemotherapy, and radiation.

New-Onset Resistant Hypertension in a Newly Diagnosed Prostate Cancer Patient

BACKGROUND

New onset resistant hypertension in a previously stable patient with chronic hypertension should lead to consideration of secondary causes. Electrolyte abnormalities are useful clues for identifying some common causes, especially mineralocorticoid excess.

CASE PRESENTATION

We report the case of a 69-year-old man who developed severe resistant hypertension despite the use of 6 antihypertensive medications, including diuretics. He had metabolic alkalosis and hypokalemia with suppressed plasma renin activity and serum aldosterone. Concurrently, he was diagnosed with small cell neuroendocrine carcinoma of the prostate gland, a rare form of prostate cancer. Despite absence of typical Cushingoid features, investigation confirmed the diagnosis of ectopic adrenocorticotropic hormone (ACTH) syndrome from neuroendocrine prostate cancer. Because of the severity of his hypercortisolism, he underwent urgent bilateral adrenalectomy for hormonal and symptomatic control. Blood pressure improved significantly and he was dismissed with a single antihypertensive agent. Unfortunately, the patient died from his cancer 1 month later.

CONCLUSION

Primary and secondary hyperaldosteronism are usually diagnosed based on measurements of aldosterone and plasma renin activity. However, if plasma renin activity and aldosterone are both low, rare causes of mineralocorticoid excess such as ectopic ACTH syndrome should be entertained.

[Neuroendocrine prostate cancer]

Neuroendocrine prostate cancer (NEPC) mostly occurs as a treatment-emergent adaptive response under the pressure of intensive androgen deprivation treatment (t-NEPC). Approximately 30-40% of patients with metastatic castration-resistant prostate cancer (mCRPC) also have neuroendocrine involvement. In contrast primary small cell prostate cancer is very rare (<1%). A t‑NEPC should be clinically suspected in patients who have particularly aggressive mCRPC but a disproportionately low prostate-specific antigen (PSA) level and elevated neuroendocrine tumor markers, such as chromogranin A and neuron-specific enolase. The initial Gleason score was shown to be an independent factor correlated to the risk of development of t‑NEPC. Treatment is oriented to that of small cell lung cancer. In patients with negative PSA levels, chemotherapy with cisplatin and etoposide is the first line treatment, for which response rates in the range of 30-60% with a median survival time of usually less than 1 year can be achieved. In patients with much higher serum PSA levels, chemotherapy with carboplatin plus docetaxel should be considered.

Neuroendocrine prostate cancer or prostatitis? An unusual false positive on gallium-68 DOTA-Tyr3-octreotate positron emission tomography/computed tomography in a patient with known metastatic neuroendocrine tumor

The importance of gallium-68 DOTA-Tyr3-octreotate (⁶⁸Ga DOTATATE) positron emission tomography/computed tomography (PET/CT) in the imaging of neuroendocrine tumors (NETs) has grown substantially over the past decade and is becoming markedly more common. We present the case of a male with known metastatic NET who underwent ⁶⁸Ga DOTATATE PET/CT for restaging, incidentally revealing intense uptake of the prostate with a maximum standard uptake value of 17.4. Due to the patient's medical history, this finding was concerning for neuroendocrine prostate cancer. However, core biopsies of the prostate were negative for malignancy and positive for chronic inflammation. Chronic prostatitis is a very common condition in adult males and is often asymptomatic. Inflammatory conditions, including prostatitis, are important causes of false-positive findings on ⁶⁸Ga DOTATATE PET/CT and should be considered as part of the differential diagnosis, even in an asymptomatic patient.

Metastases in Prostate Cancer

Prostate cancer (PCa) prognosis and clinical outcome is directly dependent on metastatic occurrence. The bone microenvironment is a favorable metastatic niche. Different biological processes have been suggested to contribute to the osteotropism of PCa such as hemodynamics, bone-specific signaling interactions, and the "seed and soil" hypothesis. However, prevalence of disseminating tumor cells in the bone is not proportional to the actual occurrence of metastases, as not all patients will develop bone metastases. The fate and tumor-reforming ability of a metastatic cell is greatly influenced by the microenvironment. In this review, the molecular mechanisms of bone and soft-tissue metastasis in PCa are discussed. Specific attention is dedicated to the residual disease, novel approaches, and animal models used in oncological translational research are illustrated.

[Neuroendocrine prostate cancer]

Neuroendocrine prostate cancer (NEPC) mostly occurs as a treatment-emergent adaptive response under the pressure of intensive androgen deprivation treatment (t-NEPC). Approximately 30-40% of patients with metastatic castration-resistant prostate cancer (mCRPC) also have neuroendocrine involvement. In contrast primary small cell prostate cancer is very rare (<1%). A t‑NEPC should be clinically suspected in patients who have particularly aggressive mCRPC but a disproportionately low prostate-specific antigen (PSA) level and elevated neuroendocrine tumor markers, such as chromogranin A and neuron-specific enolase. The initial Gleason score was shown to be an independent factor correlated to the risk of development of t‑NEPC. Treatment is oriented to that of small cell lung cancer. In patients with negative PSA levels, chemotherapy with cisplatin and etoposide is the first line treatment, for which response rates in the range of 30-60% with a median survival time of usually less than 1 year can be achieved. In patients with much higher serum PSA levels, chemotherapy with carboplatin plus docetaxel should be considered.

Mucinous and secondary tumors of the prostate

Primary mucinous tumors and secondary tumors involving the prostate gland are relatively uncommon, however they have important diagnostic, therapeutic, and prognostic implications. The primary mucinous tumors of the prostate include mucinous (colloid) adenocarcinoma of the prostate, prostatic adenocarcinoma with mucinous features, and mucinous adenocarcinoma of the prostatic urethra (mucin-producing urothelial-type adenocarcinoma of the prostate). Mucinous adenocarcinoma of the prostate is defined as a primary prostatic acinar tumor characterized by the presence of at least 25% of the tumor composed of glands with extraluminal mucin. This diagnosis can only be made in radical prostatectomy specimens. Recent studies have shown that these tumors have a similar or in some cases better prognosis than conventional prostatic adenocarcinoma treated by radical prostatectomy. The preferred terminology for tumors that are composed of <25% extraluminal mucinous component in radical prostatectomy specimens is 'prostatic adenocarcinoma with mucinous features.' All cases of prostatic adenocarcinoma with extraluminal mucinous components in prostate needle core biopsies or transurethral resection of the prostate specimens are also referred to as 'prostatic adenocarcinoma with mucinous features.' Mucinous adenocarcinoma of the prostatic urethra (mucin-producing urothelial-type adenocarcinoma of the prostate) as the name implies, does not arise from prostatic acini or ducts, and is a distinct entity that arises from the prostatic urethra usually from urethritis glandularis or glandular metaplasia with malignant transformation, and is analogous to adenocarcinoma with mucinous differentiation arising from the urinary bladder. This tumor is aggressive and has a relatively poor prognosis. The most common secondary tumors that arise from adjacent organs and spread (direct extension or metastasis) to the prostate gland, include urothelial carcinoma of the bladder and colorectal adenocarcinoma. Other secondary tumors that may involve the prostate include metastatic epithelial tumors from several other sites, malignant melanoma and soft tissue tumors.

Dual Paraneoplastic Endocrine Syndromes Heralding Onset of Extrapulmonary Small Cell Carcinoma: A Case Report and Narrative Review

OBJECTIVE

Extrapulmonary small cell carcinoma (EPSCC) is rare and frequent metastases at presentation can complicate efforts to identify a site of origin. In particular, SCC comprises <1% of prostate cancers and has been implicated in castration resistance.

METHODS

Clinical, laboratory, imaging, and pathology data are presented.

RESULTS

A 56-year-old man with locally advanced prostate adenocarcinoma on androgen deprivation therapy presented with a clogged nephrostomy tube. Laboratory results included calcium 13.8 mg/dL (8.5-10.5 mg/dL), albumin 3.6 g/dL (3.5-5 mg/dL), and potassium 2.8 mmol/L (3.5-5.2 mmol/L). Hypercalcemia investigation revealed intact PTH 19 pg/mL (16-87 pg/mL), 25-OH vitamin D 15.7 ng/mL (>30 ng/mL), and PTH-related peptide (PTHrP) 63.4 pmol/L (<2.3 pmol/L). Workup for hypokalemia yielded aldosterone 5.3 ng/dL (<31 ng/dL), renin 0.6 ng/mL/h (0.5-4 ng/mL/h), and 6:00 a.m. cortisol 82 µg/dL (6.7-22.6 µg/dL) with ACTH 147 pg/mL (no ref. range). High-dose Dexamethasone suppression testing suggested ACTH-dependent ectopic hypercortisolism. Contrast-enhanced CT findings included masses in the liver and right renal pelvis, a heterogeneous enlarged mass in the region of the prostate invading the bladder, bilateral adrenal thickening, and lytic lesions in the pelvis and spine. Liver biopsy identified epithelioid malignancy with Ki proliferation index 98% and immunohistochemical staining positive for synaptophysin and neuron-specific enolase, compatible with high-grade small cell carcinoma. Staining for ACTH was negative; no stain for CRH was available. Two weeks after chemotherapy, 6:00 a.m. cortisol normalized and CT scans showed universal improvement.

CONCLUSION

Extensive literature details paraneoplastic syndromes associated with SCC, but we report the first case of EPSCC diagnosed due to onset of dual paraneoplastic syndromes.

Histopathology of Prostate Cancer

This review focuses on histopathological aspects of carcinoma of the prostate. A tissue diagnosis of adenocarcinoma is often essential for establishing a diagnosis of prostate cancer, and the foundation for a tissue diagnosis is currently light microscopic examination of hematoxylin and eosin (H&E)-stained tissue sections. Markers detected by immunohistochemistry on tissue sections can support a diagnosis of adenocarcinoma that is primary in the prostate gland or metastatic. Histological variants of carcinoma of the prostate are important for diagnostic recognition of cancer or as clinicopathologic entities that have prognostic and/or therapeutic significance. Histological grading of adenocarcinoma of the prostate, including use of the 2014 International Society of Urological Pathology (ISUP) modified Gleason grades and the new grade groups, is one of the most powerful prognostic indicators for clinically localized prostate cancer, and is one of the most critical factors in determination of management of these patients.

Population-based study of the incidence and survival for intraductal carcinoma of the prostate

PURPOSE

The degree to which intraductal carcinoma of the prostate (IDC-P) affects clinical course remains poorly understood owing to small sample sizes from single-center studies. We sought to determine prognostic factors and outcomes associated with IDC-P in radical prostatectomy (RP) specimens.

MATERIALS AND METHODS

This is a retrospective study of RP during 2004 to 2013 using Surveillance, Epidemiology, and End Results to compare IDC-P with non-IDC-P. The effect of IDC-P on overall and disease-specific survival was assessed using Cox regression with a median follow-up of 4.8 years (interquartile range [IQR]: 2.6-7.0y; P = 0.01). Median prostate-specific antigen at diagnosis in IDC-P vs. non-IDC-P was similar (P = 0.23) at 6.2 (IQR: 4.6-13.0) vs. 6.1ng/ml (IQR: 4.6-9.8).

RESULTS

We identified 159,777 RP from 2004 to 2013, and 242 (0.002%) had IDC-P pathologic features. IDC-P was associated with a greater likelihood of extraprostatic stage, pT3/T4, 45.9% vs. 21.6% (P<0.001), higher grade, GS≥ 7, 79.3% vs. 62.7% (P<0.001), lymph node metastases, 5.8% vs. 2.4% (P<0.001), and positive surgical margins, 25.6% vs. 19.5% (P = 0.02). IDC-P was associated with a 3-fold increase in prostate cancer-specific mortality relative to non-IDC-P (hazard ratio = 3.0, 95% CI: 1.5-5.7; P<0.01). Limitations include retrospective design and potential underreporting of IDC-P that leads to underestimation of the true effect size.

CONCLUSIONS

The significance of IDC-P features has been recently recognized by the World Health Organization and it is associated with high-grade, extraprostatic features, and worse prostate cancer-specific mortality. Understanding its prognostic significance better guides adjuvant therapies and clinical trials.

Minimal (Limited) Pseudohyperplastic Prostatic Adenocarcinoma in Needle Prostatic Biopsy

Background. Study of minimum adenocarcinoma has been done almost exclusively on conventional acinar adenocarcinoma. Pseudohyperplastic adenocarcinoma can be confused with benign lesions because of its well-differentiated appearance and has not been studied when the biopsy shows few malignant glands (limited carcinoma). Methods. We reviewed 94 pseudohyperplastic adenocarcinomas diagnosed in prostatic biopsies for a period of 12 years and selected those measuring less than 1 mm or involving less than 5% of the biopsied tissue. We also reviewed 200 consecutive consultations. Results. Four (4.2%) of the 94 cases were limited pseudohyperplastic adenocarcinomas, and 3 were from consultations. Three of them were mistaken for hyperplastic nodules, prostatic adenosis, or prostatic intraepithelial neoplasm. The number of glands varied between 6 and 50 (average 23). Three nodular histological patterns were identified—nodular, adenosis-like, and pseudohyperplastic carcinoma resembling prostatic intraepithelial neoplasia. The diagnosis of adenocarcinoma was not related to the number of neoplastic glands. Histological criteria that were useful included: crowded medium to large glands, papillary infoldings, branching glands, straight luminal borders, hyperchromatic nuclei, nucleomegaly, and apparent nucleoli. Areas of transition to conventional acinar adenocarcinoma were useful in recognizing four of these neoplasms, but were barely apparent in 2 of them. Hyperchromatic nuclei were found in all cases, whereas apparent nucleoli and nucleomegaly were only present in 4. Conclusions. The architectural and cytological criteria for limited acinar adenocarcinoma are only partially useful in interpreting minimum pseudohyperplastic adenocarcinomas. Knowledge of the criteria for malignancy in both neoplasms is important in order to avoid underdiagnosis of malignancy.

[Neuroendocrine prostate cancer: Natural history, molecular features, therapeutic management and future directions]

Neuroendocrine prostate cancer is a rare malignancy with a an adverse prognostic. Histologically, It can be pure (small cells or large cells neuroendocrine carcinoma) or mixed with a adenocarcinoma component. Rarely diagnosed de novo, neuroendocrine prostate cancer is generally associated with advanced stage disease resistant to castration. As such, this histological subtype could represent an aggressive evolution of prostatic adenocarcinoma, through the epithelio-neuroendocrine transdifferentiation mechanism (phenomenon of lineage plasticity). Nonetheless, neuroendocrine prostate cancer is a heterogeneous malignancy with multiple histopathological variants showing distinct clinical features. The broad variety of molecular analyses could help to understand the ontogeny of this histological subtype and its signaling pathways. This may also allow identifying diagnostic and prognostic biomarkers as well as potential molecular targets. However, treatment options are currently limited and consist only in platinium-based chemotherapy for advanced stage disease.

Emerging Variants of Castration-Resistant Prostate Cancer

Metastatic castration-resistant prostate cancer (CRPC) is associated with substantial clinical, pathologic, and molecular heterogeneity. Most tumors remain driven by androgen receptor (AR) signaling, which has clinical implications for patient selection for AR-directed approaches. However, histologic and clinical resistance phenotypes can emerge after AR inhibition, in which the tumors become less dependent on the AR. In this review, we discuss prostate cancer variants including neuroendocrine (NEPC) and aggressive variant (AVPC) prostate cancers and their clinical implications. Improvements in the understanding of the biologic mechanisms and molecular features underlying prostate cancer variants may help prognostication and facilitate the development of novel therapeutic approaches for subclasses of patient with CRPC.

Defining the Influence of Germline Variation on Metastasis Using Systems Genetics Approaches

Cancer is estimated to be responsible for 8 million deaths worldwide and over half a million deaths every year in the United States. The majority of cancer-related deaths in solid tumors is directly associated with the effects of metastasis. While the influence of germline factors on cancer risk and development has long been recognized, the contribution of hereditary variation to tumor progression and metastasis has only gained acceptance more recently. A variety of approaches have been used to define how hereditary variation influences tumor progression and metastasis. One approach that garnered much early attention was epidemiological studies of cohorts of cancer patients, which demonstrated that specific loci within the human genome are associated with a differential propensity for aggressive tumor development. However, a powerful, and somewhat underutilized approach has been the use of systems genetics approaches in transgenic mouse models of human cancer. Such approaches are typically multifaceted, and involve integration of multiple lines of evidence derived, for example, from genetic and transcriptomic screens of genetically diverse mouse models of cancer, coupled with bioinformatics analysis of human cancer datasets, and functional analysis of candidate genes. These methodologies have allowed for the identification of multiple hereditary metastasis susceptibility genes, with wide-ranging cellular functions including regulation of gene transcription, cell proliferation, and cell-cell adhesion. In this chapter, we review how each of these approaches have facilitated the identification of these hereditary metastasis modifiers, the molecular functions of these metastasis-associated genes, and the implications of these findings upon patient survival.

Rapid progression of mixed neuroendocrine carcinoma-acinar adenocarcinoma of the prostate: A case report

The current study presents the case of a 78-year-old male with mixed neuroendocrine (NE) carcinoma-acinar adenocarcinoma of the prostate. The patient received endocrine therapy (maximal androgen blockade) after the initial diagnosis resulting in a significant decrease in serum prostate-specific antigen (PSA) level. The patient underwent transurethral resection of the prostate after 6 months of androgen-deprivation therapy for extraordinarily salient difficulty in urination, and histopathology demonstrated mixed NE carcinoma-acinar adenocarcinoma once again. The NE prostate cancer progressed rapidly even though the serum PSA was controlled at a low level on account of the endocrine therapy. Previous treatment protocols were replaced by combined chemotherapy and endocrine therapy, and the patient responded well. The patient's serum PSA remained at a low level, however, urethral dilatation for acute urinary retention was required again 5 months later and the lower urinary tract symptoms became increasingly evident. The patient eventually died of cachexia.. These findings indicate that mixed NE carcinoma-acinar adenocarcinoma has a higher degree of malignancy and that endocrine therapy for prostate cancer has a propensity to facilitate progression of this tumor.