Establishment and Validation of Prognostic Nomograms for Patients with Metastatic Pulmonary Large Cell Neuroendocrine Carcinoma.

PURPOSE: Metastatic pulmonary large cell neuroendocrine carcinoma (LCNEC) is an aggressive cancer with generally poor outcomes. Effective methods for predicting survival in patients with metastatic LCNEC are needed. This study aimed to identify independent survival predictors and develop nomograms for predicting survival in patients with metastatic LCNEC. PATIENTS AND METHODS: We conducted a retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database, identifying patients with metastatic LCNEC diagnosed between 2010 and 2017. To find independent predictors of cancer-specific survival (CSS), we performed Cox regression analysis. A nomogram was developed to predict the 6-, 12-, and 18-month CSS rates of patients with metastatic LCNEC. The concordance index (C-index), area under the receiver operating characteristic (ROC) curves (AUC), and calibration curves were adopted with the aim of assessing whether the model can be discriminative and reliable. Decision curve analyses (DCAs) were used to assess the model's utility and benefits from a clinical perspective. RESULTS: This study enrolled a total of 616 patients, of whom 432 were allocated to the training cohort and 184 to the validation cohort. Age, T staging, N staging, metastatic sites, radiotherapy, and chemotherapy were identified as independent prognostic factors for patients with metastatic LCNEC based on multivariable Cox regression analysis results. The nomogram showed strong performance with C-index values of 0.733 and 0.728 for the training and validation cohorts, respectively. ROC curves indicated good predictive performance of the model, with AUC values of 0.796, 0.735, and 0.736 for predicting the 6-, 12-, and 18-month CSS rates of patients with metastatic LCNEC in the training cohort, and 0.795, 0.801, and 0.780 in the validation cohort, respectively. Calibration curves and DCAs confirmed the nomogram's reliability and clinical utility. CONCLUSION: The new nomogram was developed for predicting CSS in patients with metastatic LCNEC, providing personalized risk evaluation and aiding clinical decision-making.

Avapritinib efficacy in primary hepatic neuroendocrine carcinoma with elevated PDGFRA expression: Insights from a PDX model study.

BACKGROUND & AIMS: Primary Hepatic Neuroendocrine Carcinoma (PHNEC) is a rare and aggressive tumor with high recurrence rates. Surgical resection remains the only therapeutic strategy. The effectiveness of tyrosine kinase inhibitors (TKIs) for PHNEC remains unclear due to limited research. METHODS: We employed immunohistochemical staining to diagnose PHNEC and assess the expression of eight tyrosine kinase receptors in tumor tissues, including VEGFRs, PDGFRA, EGFR, FGFRs et al. A patient-derived xenograft (PDX) model was established using PHNEC tumor tissues to test the efficacy of TKIs. PDX mice bearing tumors were treated with Avapritinib, an FDA-approved PDGFRA-targeting drug, at a daily oral dose of 10 mg/kg for 2 weeks. RESULTS: Pathological analysis confirmed the diagnosis of PHNEC with positive expression of Neural cell adhesion molecule (NCAM/CD56), Synaptophysin (Syn), and Somatostatin receptor 2 (SSTR-2), and negative expression of Hep (Hepatocyte Paraffin 1), a biomarker for Hepatocellular carcinoma. Notably, PDGFRA was significantly overexpressed in PHNEC tumor tissues compared to other tyrosine kinases. Avapritinib treatment significantly reduced tumor growth in PDX mice by 73.9 % (p = 0.008). Additionally, Avapritinib treatment led to a marked decrease in PDGFRA and Ki-67 expression, suggesting that it inhibits tumor cell proliferation by suppressing PDGFRA. CONCLUSION: Our findings suggest that PDGFRA is a potential therapeutic target for PHNEC, and its inhibition with Avapritinib may offer clinical benefits to patients with this rare malignancy.

Merkel cell carcinoma: updates in tumor biology, emerging therapies, and preclinical models.

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma thought to arise via either viral (Merkel cell polyomavirus) or ultraviolet-associated pathways. Surgery and radiotherapy have historically been mainstays of management, and immunotherapy has improved outcomes for advanced disease. However, there remains a lack of effective therapy for those patients who fail to respond to these established approaches, underscoring a critical need to better understand MCC biology for more effective prognosis and treatment. Here, we review the fundamental aspects of MCC biology and the recent advances which have had profound impact on management. The first genetically-engineered mouse models for MCC tumorigenesis provide opportunities to understand the potential MCC cell of origin and may prove useful for preclinical investigation of novel therapeutics. The MCC cell of origin debate has also been advanced by recent observations of MCC arising in association with a clonally related hair follicle tumor or squamous cell carcinoma in situ. These studies also suggested a role for epigenetics in the origin of MCC, highlighting a potential utility for this therapeutic avenue in MCC. These and other therapeutic targets form the basis for a wealth of ongoing clinical trials to improve MCC management. Here, we review these recent advances in the context of the existing literature and implications for future investigations.

Pure large-cell neuroendocrine carcinoma of the ovary with a somatic BRCA1 mutation: The first reported case and the review of the literature.

Pure large-cell neuroendocrine carcinomas of the ovary are extremely rare, so there is a lack of molecular information on this type of cancer. Herein, we presented a pure primary large-cell neuroendocrine carcinomas of the ovary in a 72-year-old female with a pathogenic somatic mutation at the c.5332+1g>a splice site of the BRCA1 gene and with no TP53 mutation. She was uneventful 32 months after the operation and chemotherapies. To the best of our knowledge, this is the first report of a BRCA1 somatic mutation in the ovary large-cell neuroendocrine carcinomas. Testing BRCA1/2 mutations in patients with large ovarian cell neuroendocrine carcinomas might provide an opportunity for their future target treatments. It would expand our understanding.

Does the size of the neuroendocrine-carcinoma component determine the prognosis of gallbladder cancer?

Background: Gallbladder mixed neuroendocrine-non-neuroendocrine neoplasm generally consists of a gallbladder neuroendocrine tumor and a non-neuroendocrine component. The World Health Organization (WHO) in 2019 established a guideline requiring each component, both neuroendocrine and non-neuroendocrine, to account for a minimum of 30% of the tumor mass. Methods: Patients after surgery resection and diagnosed at microscopy evaluation with pure gallbladder neuroendocrine carcinoma (GBNEC), gallbladder mixed adeno-neuroendocrine carcinoma (GBMANEC, GBNEC≥30%), and gallbladder carcinoma mixed with a small fraction of GBNEC (GBNEC <30%) between 2010 and 2022 at West China Hospital of Sichuan University were collated for the analyses. Demographic features, surgical variables, and tumor characteristics were evaluated for association with patients' overall and recurrence-free survival (OS and RFS). Results: The study included 26 GBNEC, 11 GBMANEC, 4 gallbladder squamous-cell carcinoma (GBSCC), and 7 gallbladder adenocarcinoma (GBADC) mixed with a small fraction of GBNEC. All patients had stage III or higher tumors (AJCC8th edition). The majority of included patients (79.17%) underwent curative surgical resection (R0), with only ten patients having tumoral resection margins. In the analysis comparing patients with GBNEC percentage (GBNEC≥30% vs. GBNEC<30%), the basic demographics and tumor characteristics of most patients were comparable. The prognosis of these patients was also comparable, with a median OS of 23.65 months versus 20.40 months (P=0.13) and a median RFS of 17.1 months versus 12.3 months (P=0.24). However, patients with GBADC or GBSCC mixed with GBNEC <30% had a statistically significant decreased OS and RFS (both P<0.0001)) compared with GBNEC and GBMANEC. Patients with GBNEC who exhibited advanced tumor stages and lymphovascular invasion had a higher risk of experiencing worse overall survival (OS) and recurrence-free survival (RFS). However, a 30% GBNEC component was not identified as an independent risk factor. Conclusion: Patients with GBNEC were frequently diagnosed at advanced stages and their prognosis is poor. The 30% percentage of the GBNEC component is not related to the patient's survival.

Large cell neuroendocrine carcinoma of the cervix: a case report.

Large Cell Neuroendocrine Carcinoma (LCNEC) of the cervix is an extremely rare but highly aggressive type of cervical cancer and it requires multimodal therapy to improve their quality of life. At present, there are no established, standardized treatment protocols for managing large cell neuroendocrine carcinoma of the cervix. In this report, we present a case of a patient with cervical LCNEC, Who was a 39-year-old woman who presented with irregular vaginal bleeding accompanied by lower abdominal distension for over a month. Examination revealed a cauliflower-like cervical mass approximately 4cm in diameter, with the normal cervical architecture distorted and partially fused to the vaginal wall. Following further investigations, the stage assigned was IVB, and who was started on neoadjuvant chemotherapy with the TC (paclitaxel + carboplatin) regimen but during neoadjuvant chemotherapy, The patient developed a vaginal urinary leakage. Then, The patient underwent a comprehensive treatment regimen that included pelvic exenteration, urinary system reconstruction, pelvic floor reconstruction, and chemotherapy. Given the patient's positive immunohistochemistry for EGFR, the treatment was combined with the anti-angiogenic drug, bevacizumab. The patient achieved complete remission following the comprehensive treatment. Through this case to explore individualized treatment for cervical LCNEC.

Primary large cell neuroendocrine carcinoma of the bladder: A case report.

BACKGROUND: Large cell neuroendocrine carcinoma (LCNEC) of the bladder is a rare non-urothelial tumor of the bladder. The treatment of LCNEC of the bladder is different from that of urothelial carcinoma (UC); therefore, early and accurate diagnosis is particularly important. As LCNEC of the bladder is rare and its clinical symptoms and radiographic features are similar to those of urothelial tumors, the clinical diagnosis of the disease remains challenging. CASE SUMMARY: We report a 72-year-old female patient who presented with gross hematuria for 3 mo. A solitary tumor located in the anterior wall of the bladder was found by cystoscopy. Pathological examination after biopsy suggested UC of the bladder in the absence of immunohistochemical assessment. The patient underwent partial cystectomy and was finally diagnosed with LCNEC (pT2bN0M0) based on the results of postoperative immunohistochemical examination. During the 10-mo follow-up, no signs of tumor recurrence or metastasis were found. CONCLUSION: Immunohistochemical examination is essential for diagnosing LCNEC of the bladder. Accurate diagnosis and multidisciplinary treatment in the early stage of the disease are crucial for improving the prognosis.

Small-Cell Neuroendocrine Cervical Carcinoma Mimicking a Polyp in a 20-Year-Old Patient With a Five-Year Follow-Up: A Case Report.

Small-cell neuroendocrine cervical carcinoma (NECC) is a rare histology, and diagnosis and treatment of this condition are challenging because of its rarity, non-specific abdominopelvic symptoms, and less favorable prognosis compared to other cervical cancers. Here, we present a case of a 20-year-old patient diagnosed with small-cell NECC, defined within a cervical polyp, initially mimicking a benign lesion. Because of the difficulty in diagnosis, the patient underwent thorough diagnostics and interventions, including imaging, histopathology, and immunohistochemistry. Initially, the patient underwent a distinctive treatment plan encompassing four cycles of cisplatin and etoposide chemotherapy with minimal side effects. Subsequently, she received comprehensive surgical interventions, including hysterectomy, lymphadenectomy, and bilateral salpingectomy. Ovarian preservation, justified by the patient's youth and small cervical lesions (<4 cm) without parametrial disease or metastatic signs, was pursued. For long-term outcomes, the patient demonstrated no metastasis or recurrence during a five-year follow-up. This case emphasizes the requirement for strengthened awareness of neuroendocrine tumors in cervical masses, particularly in young patients, and the importance of individualized treatment approaches for optimal clinical outcomes. Continued documentation of such cases increases our understanding of managing infrequent cervical malignancies.

EBV-positive small cell neuroendocrine carcinoma of nasopharynx as a probably unique subtype of neuroendocrine carcinoma: a clinicopathologic study of three cases and literature review.

BACKGROUND: There is currently scarcity of information on small cell neuroendocrine carcinoma of the nasopharynx (SCNEC-nasopharynx). It is believed that this type of cancer is not associated with Epstein-Barr virus (EBV) infection and is indistinguishable from classic SCNEC occurring in other organs. MATERIALS AND METHODS: Herein we provided 3 cases of nasopharyngeal mass in our hospital, two males and one female. On admission, these patients were considered nasopharyngeal carcinoma with lymph node metastasis, and one of them had liver metastasis. The nasopharyngeal mucosal tissues were biopsied for pathological examination including immunohistochemistry and in situ hybridization. PubMed database was searched for articles about SCNEC-nasopharynx published up to April 2024 in any language. RESULT: The 3 cases had similar histological features of SCNEC in other organs but differed in rich- tumor-infiltrating lymphocytes (TILs). All of them stained for pancytokeratin (panCK) and epidermal growth factor receptor (EGFR). Case 1 and Case 2 diffusely expressed insulinoma-associated protein 1(INSM-1) and synaptophysin (Syn), Case 3 strongly stained for CD56 and Syn. Immunostaining of all 3 cases for p40, p63, TTF-1, CK20, S-100 and NUT showed negative. BRG-1, INI-1 and Rb were retained. And p53 all showed wild-type expression. The Ki-67 labeling indiced of case 1, 2, and 3 were 80%, 90%, and 80%, respectively. In situ hybridization showed strong and uniform nuclear positivity of EBV-encoded small RNAs (EBER) in the neoplastic cells of 3 cases. CONCLUSION: EBV-positive SCNEC-nasopharynx was exactly rare. The origin of this tumor is still controversial. It may originate from EBV-infected mucosal epithelium like nasopharyngeal carcinoma. Based on our cases and relevant literature, we found EBV-positive SCNEC-nasopharynx as a probably site-specific subtype of SCNEC with differing pathogenetic mechanism. The subtype not only virus positivity but also that it was associated with TILs and did not show p53 or Rb alterations by immunohistochemistry. It may be more responsive to treatment and have a better prognosis than classic SCNEC. We will continue to follow-up these patients and collect additional cases to further understand the unique biology of this rare solid tumor.

Sex Differences in the Survival of Patients with Neuroendocrine Neoplasms: A Comparative Study of Two National Databases.

BACKGROUND: Neuroendocrine neoplasms (NENs) are increasing in incidence globally. Previous analysis of the UK cancer database (National Cancer Registration and Analysis Service (NCRAS)) showed a notable female survival advantage in most tumour sites. This study aims to compare NCRAS to the Surveillance, Epidemiology, and End Results Program (SEER) to validate these results using the same statistical methods. METHODS: A total of 14,834 and 108,399 patients with NENs were extracted from NCRAS and SEER, respectively. Sixty-months survival for both males and females for each anatomical site of NENs were calculated using restricted mean survival time (RMST) and Kaplan-Meier Survival estimates. The sixty-month RMST female survival advantage (FSA) was calculated. RESULTS: FSA was similar in NCRAS and SEER. The highest FSA occurred in lung and stomach NENs. CONCLUSIONS: The data from SEER confirm the findings published by NCRAS. Female survival advantage remains unexplained.

Update in the management of gastroenteropancreatic neuroendocrine tumors.

Neuroendocrine neoplasms are a diverse group of neoplasms that can occur in various areas throughout the body. Well-differentiated neuroendocrine tumors (NETs) most often arise in the gastrointestinal tract, termed gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Although GEP-NETs are still uncommon, their incidence and prevalence have been steadily increasing over the past decades. The primary treatment for GEP-NETs is surgery, which offers the best chance for a cure. However, because GEP-NETs are often slow-growing and do not cause symptoms until they have spread widely, curative surgery is not always an option. Significant advances have been made in systemic and locoregional treatment options in recent years, including peptide-receptor radionuclide therapy with α and ß emitters, somatostatin analogs, chemotherapy, and targeted molecular therapies.

Clinical Challenges and Management Strategies in Pulmonary Large-Cell Neuroendocrine Carcinoma.

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a rare but aggressive malignancy of the lung. Its nonspecific presentation and propensity for severe disease at the time of diagnosis create challenges in treatment. We report a case of an asymptomatic 61-year-old female who was incidentally found to have a pulmonary nodule after a fall. Upon further workup, she was found to have an aggressive LCNEC. The patient underwent a robotic-assisted left upper lobectomy, which was complicated by left lower lobe bronchus kinking and post-obstructive atelectasis, warranting further management by thoracic surgery. The patient additionally underwent video-assisted thoracoscopic surgery (VATS), open thoracotomy, pneumopexy, and bronchial stenting. This case highlights the need for strategies for early detection in at-risk populations. A multidisciplinary approach, which may involve both medical and surgical subspecialties, is essential in the management of this complex disease from the time of diagnosis to follow-up postoperatively to achieve the best clinical outcome.

An elderly case of paraneoplastic anti-NMDA receptor encephalitis associated with large cell neuroendocrine carcinoma of the lung.

BACKGROUND: Recent studies have suggested that N-methyl-D-aspartate (NMDA) receptors are involved in the cell proliferation in several tumors. However, there have been no reports demonstrating the expression of NR1 subunit of the NMDA receptor in large cell neuroendocrine carcinoma (LCNEC). CASE PRESENTATION: Here, we report the first elderly case of paraneoplastic anti-NMDA receptor encephalitis associated with LCNEC of the lung with NR1 expression. Of note, NR1 subunit expression in the tumor cells of the present case was confirmed by immunohistochemistry (IHC). Radiation therapy and immunotherapies, such as corticosteroids and intravenous immunoglobulin (IVIG), shrank the tumors and improved neurological symptoms in the present case. Additionally, we also confirmed the expression of NR1 in the tumor cells obtained from three other cases with LCNEC of the lung at our hospital by IHC. CONCLUSION: Our IHC results indicate that LCNEC generally expresses NR1 subunit and NMDA receptor may be involved in the tumor development and growth.

Mixed neuroendocrine and adenocarcinoma of gastrointestinal tract: A complex diagnosis and therapeutic challenge.

In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction. Mixed neuroendocrine and non-neuroendocrine neoplasms of the gastrointestinal system are rare heterogeneous group of tumors characterized by a high malignant potential, rapid growth, and poor prognosis. Due to the rarity of these cancers, the standard therapy is poorly defined. The diagnosis of these tumors is based on combination of morphological features, immunohistochemical and neuroendocrine and epithelial cell markers. Both endocrine and epithelial cell components can act independently of each other and thus, careful grading of each component separately is required. These cancers are aggressive in nature and the potential of each component has paramount importance in the choice of treatment and response. Regardless of the organ of origin, these tumors portend poor prognosis with increased proportion of neuroendocrine component. Multidisciplinary services and strategies are required for the management of these mixed malignancies to provide the best oncological outcomes. The etiopathogenesis of these mixed tumors remains obscure but poses interesting question. We briefly discuss a few salient points in this editorial.

Primary Hepatic Neuroendocrine Carcinoma: A Rare Entity.

Neuroendocrine tumors are typically low-malignancy growths arising from neuroectodermal cells of neural crest origin. Neuroendocrine carcinoma, on the other hand, represents a high-malignancy form of these tumors. While rare in the liver, they often indicate metastasis when present. We present a unique case of incidentally discovered primary hepatic neuroendocrine carcinoma. Initially, the patient's management was based on misleading radiological findings. However, histopathology confirmed the diagnosis, with subsequent imaging ruling out an extrahepatic source. Despite this, the patient opted against surgical intervention, resulting in a fatal outcome. This case underscores the critical importance of prompt diagnosis and intervention to avert adverse outcomes.

Small Cell Carcinoma Prostate: A Case Report with Findings on 18-F FDG PET/CT.

Small-cell carcinoma of the prostate (SCCP) is a rare and very aggressive malignancy with neuroendocrine differentiation. In contrast to conventional prostate adenocarcinoma, SCCP is an aggressive carcinoma and portends to have a poor prognosis. Around 50% of these patients have metastatic disease at the first clinical presentation. We report the findings of 18-F fluorodeoxyglucose positron emission tomography/computed tomography in a case of histologically proven SCCP with an unusual finding of the left internal mammary lymph node.

Efficacy of first-line chemotherapy based on primary site of tumor versus etoposide-platinum in advanced gastroenteropancreatic neuroendocrine carcinoma.

Background: Gastroenteropancreatic neuroendocrine carcinomas (GEP-NECs) constitute a rare and aggressive group of malignancies usually with widespread disease. There are limited studies on GEP-NECs, and therefore, we aim to acquire more information on the clinical features, treatment regimens, and prognosis. Methods: Data from advanced GEP-NECs patients who had not previously received systemic treatment for advanced disease at The First Affiliated Hospital of Nanjing Medical University from 2010 to 2022 were retrospectively collected. Relationships between clinical-pathological features, treatment regimens, and prognosis were investigated using Kaplan-Meier curves and cox regression models. Results: A total of fifty-four patients were enrolled in the study. The median age was 65.5 years and 79.6% were male. At diagnosis, 51.9% and 3.7% of patients developed liver and brain metastasis respectively. Sixteen (29.6%) patients received chemotherapy according to primary site of tumor (PST), while thirty-eight (70.4%) were treated with etoposide-platinum (EP) regimen, which based on the first-line treatment of advanced small cell lung cancer (SCLC). No significant differences on progression-free survival (PFS) and response rate were observed between these two groups. Univariate survival analysis showed that liver metastasis, elevated baseline serum carcinoembryonic antigen, elevated baseline serum neuron-specific enolase, elevated baseline serum lactate dehydrogenase, and elevated baseline serum neutrophil-to-lymphocyte ratio (NLR) were associated with shorter PFS. After multivariate analysis, elevated NLR was the only factor that remained significantly associated with shorter PFS (P=0.01). Conclusions: GEP-NECs are aggressive neoplasms, of which elevated NLR is proven to be an independent negative predictor. Treatment regimens based on PST are not inferior to regiments based on SCLC (EP) for GEP-NECs patients. Large-scale, prospective randomized controlled trials are required to establish the standard of care.

A morphological and immunohistochemical study of ductal carcinoma in situ, invasive breast carcinoma of no special type, and mucinous carcinoma of the breast in comparison with solid papillary carcinoma regarding neuroendocrine marker expression.

The exact relationship between solid papillary carcinoma (SPC) and invasive breast carcinoma of no special type (IBC-NST) with neuroendocrine differentiation and SPC and mucinous carcinoma (MC) of the breast remains unclear. To clarify the relationship, we conducted a comparative study of morphological and neuroendocrine features between ductal carcinoma in situ (DCIS, 72 cases) and SPC in situ (35 cases), and IBC-NST (103 cases) and invasive SPC (92 cases). We also conducted the study between MC associated with and without SPC. Synaptophysin, chromogranin A, and INSM1 were employed for the immunohistochemical study. IBC-NST had occasionally a morphological similarity with invasive SPC. While 123 of 127 cases with SPC demonstrated diffuse staining with one or more of the neuroendocrine markers, the only one case of DCIS and none of IBC-NST showed it. Type B was observed in 16 of 18 cases of MC associated with SPC and in 13 of 33 cases of MC without it. All the cases of MC with SPC and 6 of 33 cases without it showed diffuse staining for at least one of the neuroendocrine markers. In conclusion, a careful distinction between invasive SPC and IBC-NST with neuroendocrine differentiation is required. We assume that SPC in situ is a potential candidate for precursor of IBC-NST with neuroendocrine differentiation. MC of the breast is suggested to have two pathogenetic pathways through SPC in situ or non-SPC in situ. SPC in situ is thought to be less common as a precursor of MC than non-SPC in situ.

Dermoscopic characteristics of Merkel cell carcinoma.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare, aggressive, cutaneous tumour with high mortality and frequently delayed diagnosis. Clinically, it often manifests as a rapidly growing erythematous to purple nodule usually located on the lower extremities or face and scalp of elderly patients. There is limited available data on the dermoscopic findings of MCC, and there are no specific features that can be used to definitively diagnose MCC. AIM OF THE STUDY: Here, we aimed to summarize existing published literature on dermatoscopic and reflectance confocal microscopy (RCM) features of MCC. MATERIALS AND METHODS: To find relevant studies, we searched the PubMed and Scopus databases from inception to April 12, 2023. Our goal was to identify all pertinent research that had been written in English. The following search strategy was employed: (" dermoscopy" OR " dermatoscopy" OR " videodermoscopy" OR " videodermatoscopy" OR " reflectance confocal microscopy") AND " Merkel cell carcinoma". Two dermatologists, DK and GE, evaluated the titles and abstracts separately for eligibility. For inclusion, only works written in English were taken into account. RESULTS: In total 16 articles were retrieved (68 cases). The main dermoscopic findings of MCC are a polymorphous vascular pattern including linear irregular, arborizing, glomerular, and dotted vessels on a milky red background, with shiny or non-shiny white areas. Pigmentation was lacking in all cases. The RCM images showed a thin and disarranged epidermis, and small hypo-reflective cells that resembled lymphocytes arranged in solid aggregates outlined by fibrous tissue in the dermis. Additionally, there were larger polymorphic hyper-reflective cells that likely represented highly proliferative cells. CONCLUSION: Dermoscopic findings of MCC may play a valuable role in evaluating MCC, aiding in the early detection and differentiation from other skin lesions. Further prospective case-control studies are needed to validate these results.

Corrigendum: Cardiac infarction caused by PD-1 inhibitor during small cell neuroendocrine carcinoma of the ureter treatment: a case report.

[This corrects the article DOI: 10.3389/fonc.2023.1114397.].