The Molecular Basis and Clinical Consequences of Chronic Inflammation in Prostatic Diseases: Prostatitis, Benign Prostatic Hyperplasia, and Prostate Cancer

Chronic inflammation is now recognized as one of the major risk factors and molecular hallmarks of chronic prostatitis, benign prostatic hyperplasia (BPH), and prostate tumorigenesis. However, the molecular mechanisms by which chronic inflammation signaling contributes to the pathogenesis of these prostate diseases are poorly understood. Previous efforts to therapeutically target the upstream (e.g., TLRs and IL1-Rs) and downstream (e.g., NF-κB subunits and cytokines) inflammatory signaling molecules in people with these conditions have been clinically ambiguous and unsatisfactory, hence fostering the recent paradigm shift towards unraveling and understanding the functional roles and clinical significance of the novel and relatively underexplored inflammatory molecules and pathways that could become potential therapeutic targets in managing prostatic diseases. In this review article, we exclusively discuss the causal and molecular drivers of prostatitis, BPH, and prostate tumorigenesis, as well as the potential impacts of microbiome dysbiosis and chronic inflammation in promoting prostate pathologies. We specifically focus on the importance of some of the underexplored druggable inflammatory molecules, by discussing how their aberrant signaling could promote prostate cancer (PCa) stemness, neuroendocrine differentiation, castration resistance, metabolic reprogramming, and immunosuppression. The potential contribution of the IL1R-TLR-IRAK-NF-κBs signaling molecules and NLR/inflammasomes in prostate pathologies, as well as the prospective benefits of selectively targeting the midstream molecules in the various inflammatory cascades, are also discussed. Though this review concentrates more on PCa, we envision that the information could be applied to other prostate diseases. In conclusion, we have underlined the molecular mechanisms and signaling pathways that may need to be targeted and/or further investigated to better understand the association between chronic inflammation and prostate diseases.

Large cell neuroendocrine carcinoma of the nasal cavity: an extremely rare and new distinct entity

Large cell neuroendocrine carcinoma (LCNEC) is a rare but distinct entity of nasal cavity carcinomas. Only a very few cases have been reported in the nasal cavity. Its treatment is not well established. We report the case of a LCNEC in a 70 years old patient who presented with right nasal obstruction and epistaxis since 2 months. Diagnosis was confirmed by histological and immunohistochemical study. The patient underwent complete endoscopic removal of the tumor combined to adjuvant chemoradiotherapy. After 6 month follow-up, the patient was in complete clinical and radiological remission. We will discuss in this paper the various epidemiology, clinical features, pathological findings, differential diagnosis, and evolution of treatment of this uncommon malignancy in the light of current knowledge. Optimal treatment strategies are yet to be determined for this rare malignancy with poor prognosis including surgery and chemoradiotherapy.

Large Cell Neuroendocrine Carcinoma of the Head and Neck: A Clinicopathologic Series of 10 Cases With an Emphasis on HPV Status

Large cell neuroendocrine carcinoma (LCNEC) is a high-grade neuroendocrine neoplasm first described in the lung and subsequently well documented in many other anatomic sites. It has only recently been recognized that LCNEC can also occasionally arise in the head and neck. The role of human papillomavirus (HPV), which is associated with some small cell carcinomas of the head and neck, has not been investigated for LCNEC. We sought to further characterize the histologic, immunophenotypic, and clinical features of LCNEC and also investigate the role of HPV in this newly described group of tumors. The surgical pathology archives of 2 large academic institutions were searched for cases of LCNEC arising in the head and neck. p16 immunohistochemistry and HPV in situ hybridization were performed, and clinical information was obtained from electronic medical records. Ten cases of head and neck LCNEC were identified. The tumors arose in 6 men and 4 women ranging in age from 14 to 70 years (median, 63.5 y). The primary tumor sites were the oropharynx (n=4), the sinonasal tract (n=3), and the larynx (n=3). The LCNECs consisted of nests and trabeculae of medium-large cells with abundant cytoplasm, coarse chromatin, and prominent nucleoli with very high mitotic rates. The tumor nests were often associated with necrosis, peripheral palisading, and rosette formations. The LCNECs were positive for pan-cytokeratin and at least 1 neuroendocrine marker (most often synaptophysin) and were largely negative for p63 (focal staining in 2/10) and CK5/6 (staining in 1/10). The LCNECs demonstrated aggressive clinical behavior: 8 of 10 presented with advanced disease, 5 of 10 died, with 4 more living but with persistent tumor. Three of 10 LCNECs were HPV-related (HPV-LCNEC); they arose in the oropharynx (n=2) and sinonasal tract (n=1). The HPV-LCNECs did not differ from the HPV-negative tumors in histologic appearance or behavior: 2 patients with HPV-LCNEC have died because of their disease and 1 remains alive but with widespread metastases. LCNEC is a rare but distinct form of head and neck carcinoma that exhibits aggressive clinical behavior. A subset of oropharyngeal and sinonasal LCNEC is HPV related, but the presence of HPV may not impart a more favorable prognosis. Because of its aggressive behavior, LCNEC should be distinguished from moderately differentiated neuroendocrine carcinoma and squamous cell carcinoma. The morphology of LCNEC overlaps considerably with the nonkeratinizing appearance of HPV-related squamous cell carcinoma, and as a result a high index of suspicion is needed to identify LCNEC. Immunohistochemical studies for synaptophysin and p63 are helpful tools for making this distinction.

Clinical recommendations on the treatment of neuroendocrine carcinoma of the larynx: A meta-analysis of 436 reported cases

BACKGROUND

Current recommendations on the treatment of neuroendocrine carcinoma of the larynx (NCL) are based on anecdotal evidence. With this meta-analysis, our purpose was to provide clinicians with more substantiated guidelines in order to improve the treatment outcome of the patients affected with NCL.

METHODS

A structured literature search for all research concerning NCL was performed against the MEDLINE and EMBASE databases. Available data was normalized, pooled, and statistically analyzed.

RESULTS

Four hundred thirty-six cases of NCL were extracted from 182 studies, of which 23 were typical carcinoid, 163 were atypical carcinoid, 183 were small-cell neuroendocrine carcinoma, 29 were large-cell neuroendocrine carcinoma, and 38 were unspecified carcinoid tumors. The 5-year disease-specific survival (DSS) was 100% for typical carcinoid, 53% for atypical carcinoid, 19% for small-cell neuroendocrine carcinoma, and 15% for large-cell neuroendocrine carcinoma (p < .001). Patients with an atypical carcinoid treated with surgery had better DSS than those treated with radiotherapy (60% vs 54%; p = .035). Postoperative radiotherapy did not result in better DSS in atypical carcinoid. Patients with an atypical carcinoid, not undergoing surgical treatment of the neck, developed isolated regional recurrence in 30% of cases (p = .001). Radiochemotherapy yielded the best DSS for small-cell neuroendocrine carcinoma compared to other modalities (31% vs 13%; p = .001).

CONCLUSION

Typical carcinoid can be treated by local excision alone. Atypical carcinoids do not seem to respond well to radiotherapy and are best managed through radical surgical excision in combination with elective neck dissection. Patients with small-cell neuroendocrine carcinoma or large-cell neuroendocrine carcinoma seem to benefit most from chemoradiotherapy.

Oligometastatic Large Cell Neuroendocrine Carcinoma of the Brain Without Radiologically Detected Primary

A 60-year-old Polish male was admitted into our hospital with complaint of right-sided lower extremity weakness. CT of head showed a left frontal 2.6 × 1.5 cm mass. Staging work-up did not show any other associated lesions in the chest or abdomen. Brain tumor was resected with histology consistent with large cell neuroendocrine carcinoma with most likely lung primary because of TTF-1 positivity. Following recovery from surgery, he had external beam radiation therapy to the brain and systemic chemotherapy with four cycles of cisplatin/etoposide. Patient is alive and doing well 6 months post diagnosis with no evidence of recurrence.

Large cell neuroendocrine carcinoma of the head and neck

Large cell neuroendocrine carcinoma is a poorly differentiated neuroendocrine carcinoma that usually occurs in the lung. Although rare in the head and neck, salivary and mucosal subtypes are recognized. This article describes their characteristic light microscopic and immunohistochemical features and highlights the importance of accurate diagnosis, management and prognostic implications.

Terminology and classification of neuroendocrine neoplasms of the larynx

OBJECTIVES

To review the history and literature on neuroendocrine neoplasms of the larynx and discuss the terminology and classification of these tumors.

STUDY DESIGN

Contemporary review.

METHODS

Published journal articles identified through PubMed and conference proceedings were reviewed.

RESULTS

Neuroendocrine neoplasms of the larynx include both epithelial (carcinomas) and neural-type lesions (paragangliomas).The nomenclature of these tumors has changed quite a bit over time, but recently, clearer categories have emerged that are biologically meaningful. They can overlap clinically and histologically so that segregation into the clinically relevant subtypes can be difficult, but it is extremely important to do so as they have a wide range of behaviors going from benign to rapidly fatal.

CONCLUSIONS

Neuroendocrine neoplasms of the larynx can be clearly categorized into the five tumor types: typical carcinoid, atypical carcinoid, small cell neuroendocrine carcinoma, large cell neuroendocrine carcinoma, and paraganglioma. These have concrete biologic and clinical significance and clearly dictate patient treatment.