Cell Neuroendocrine Carcinoma Research Articles

Clinical and Radiological Assessment of Patients with Lung Cancer Using Chest CT Scan: An Observational Study in a Barcelona Hospital, Spain

Introduction: Lung cancer is one of the most common and deadliest types of cancer in the world. Chest CT scan is an important diagnostic tool for detecting and evaluating lung cancer. This study aimed to assess the clinical and radiological characteristics of patients with lung cancer who underwent chest CT scans at Barcelona Hospital, Spain. Methods: This research is a retrospective observational study involving 1059 patients diagnosed with lung cancer who underwent chest CT scans between 2018-2023. Patient data were collected from electronic medical records, including demographic information, clinical symptoms, CT scan findings, and histopathological diagnosis results. Results: The most common clinical symptom was cough (83.0%), followed by shortness of breath (58.8%), chest pain (45.6%), coughing up blood (20.3%), and weight loss (17, 9%). The most common CT scan finding was lung nodules (80.6%), followed by consolidation (39.7%) and pleural effusion (26.9%). The most common histopathologic diagnosis was adenocarcinoma (40.4%), followed by squamous cell carcinoma (29.5%), large cell carcinoma (17.9%), and neuroendocrine cell carcinoma (12.3%). Conclusion: This study provides an overview of the clinical and radiological characteristics of patients with lung cancer who underwent chest CT scans at the Barcelona Hospital, Spain. The findings of this study may help doctors in diagnosing and managing patients with lung cancer.

TREM1/DAP12 based novel multiple chain CAR-T cells targeting DLL3 show robust anti-tumour efficacy for small cell lung cancer.

Small cell lung cancer (SCLC), recognized as the most aggressive subtype of lung cancer, presents an extremely poor prognosis. Currently, patients with small cell lung cancer face a significant dearth of effective alternative treatment options once they experience recurrence and progression after first-line therapy. Despite the promising efficacy of immunotherapy, particularly immune checkpoint inhibitors in non-small cell lung cancer (NSCLC) and various other tumours, its impact on significantly enhancing the prognosis of SCLC patients remains elusive. DLL3 has emerged as a compelling target for targeted therapy in SCLC due to its high expression on the membranes of SCLC and other neuroendocrine carcinoma cells, with minimal to no expression in normal cells. Our previous work led to the development of a novel multiple chain chimeric antigen receptor (CAR) leveraging the TREM1 receptor and DAP12, which efficiently activated T cells and conferred potent cell cytotoxicity. In this study, we have developed a DLL3-TREM1/DAP12 CAR-T (DLL3-DT CAR-T) therapy, demonstrating comparable anti-tumour efficacy against SCLC cells in vitro. In murine xenograft and patient-derived xenograft models, DLL3-DT CAR-T cells exhibited a more robust tumour eradication efficiency than second-generation DLL3-BBZ CAR-T cells. Furthermore, we observed elevated memory phenotypes, induced durable responses, and activation under antigen-presenting cells in DLL3-DT CAR-T cells. Collectively, these findings suggest that DLL3-DT CAR-T cells may offer a novel and potentially effective therapeutic strategy for treating DLL3-expressing SCLC and other solid tumours.

Lethal disseminated intravascular coagulation induced by primary and metastatic neuroendocrine prostate cancer

IntroductionNeuroendocrine prostate cancer has a poor prognosis. Although disseminated intravascular coagulation associated with malignancy can be lethal, it very rarely occurs among patients with primary neuroendocrine prostate cancer.Case presentationAn 80‐year‐old man presented to our hospital with bloody sputum. Blood examination indicated disseminated intravascular coagulation. Serum levels of prostate‐specific antigen and neuron‐specific enolase were 44.274 and 176 ng/mL, respectively. Core needle biopsies of an irregular mass in the prostate and a metastatic tumor in the left iliac bone showed similar neuroendocrine carcinoma cells. Hence, the patient was diagnosed with disseminated intravascular coagulation associated with primary and metastatic neuroendocrine prostate cancer. Unfortunately, he passed away 3 weeks after the biopsies.ConclusionGiven the difficulty of effectively treating metastatic neuroendocrine prostate cancer among patients in poor physical condition due to disease progression, identifying a new well‐tolerated treatment modality is imperative.

Primary Oral Mixed Neuroendocrine-Non-neuroendocrine Neoplasm (MiNEN): A Rare Case Report and Review of the Literature.

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare tumors recently characterized by the presence of both neuroendocrine and non-neuroendocrine components within the same tumor tissue. Although MiNEN found their place in the WHO classification for various organs, this composite tumor in the head and neck region remains exceptionally rare. We present a case of primary oral MiNEN in a 64-year-old male located on the left side of lower gingiva. Biopsy raised suspicion of neuroendocrine carcinoma (NEC) and the patient underwent partial mandibulectomy. The resected specimen showed two distinct components of NEC and squamous cell carcinoma (SCC) with the confirmation of immunohistochemical markers. There has been no sign of recurrence nor metastasis 6years after the surgery. In addition, we have conducted a review of published cases with potential relevance to this entity, resulting in five cases. The diverse terminology reinforces the need for a standardized classification system of oral/head and neck MiNENs.

Comparison of clinicopathological features and survival analysis between esophageal neuroendocrine carcinoma and esophageal squamous cell carcinoma based on the SEER database, alongside nomogram analysis for esophageal neuroendocrine carcinoma.

Esophageal neuroendocrine carcinoma (ENEC) is a rare subtype of esophageal cancer (EC). It presents distinctive clinical and pathological features in comparison to esophageal squamous cell carcinoma (ESCC). To better elucidate the disparities between the two and establish a prognostic prediction model for ENEC, we conducted this study. Data of ENEC and ESCC patients (1975 to 2016) were extracted from the Surveillance, Epidemiology and End Results (SEER) database. Patients with a confirmed pathological diagnosis of ENEC and ESCC were enrolled in the study. The Chi-square test was employed to compare categorical variables, and the median survival time was analyzed using the Kaplan-Meier curve. Training and validation groups were randomly assigned at a ratio of 7:3. Factors with a significance level of <0.05 in the multifactor regression model as well as age were integrated into the nomogram model. Concordance index (C-index), calibration curves, and decision curve analyses (DCA) were generated for model validation. This study encompassed a total of 737 ENEC patients and 29,420 ESCC. Compared to ESCC, ENEC patients had higher probability of liver metastasis (13.8% vs. 1.9%, P<0.001), poor differentiation (68.0% vs. 37.1%, P<0.001), and late SEER stage (52.8% vs. 26.9%, P<0.001). Patients who received either surgery, radiotherapy (RT), or chemotherapy had a significantly longer disease-specific survival (DSS) and overall survival (OS) (all P<0.001). After propensity score matching (PSM), ENEC patients were associated with shorter DSS (7.0 months vs. not reached, P<0.0001) and OS (7.0 vs. 12.0 months, P<0.0001) compared to ESCC. Race, SEER stage, surgery, RT, and chemotherapy were identified as predictors of DSS and were incorporated into the nomogram model together with age. The validation of the model using C-index (0.751 and 0.706, respectively) and calibration curves reflected the better discrimination power of the model. In addition, DCA supported the favorable potential clinical effect of the predictive model. Lastly, a risk classification based on the nomogram also verified the reliability of the model. ENEC and ESCC exhibit distinct clinicopathological features. Patients with ENEC experience significantly poorer survival outcomes compared to those with ESCC. Surgical intervention, radiation therapy, and chemotherapy significantly improve OS and DSS for ENEC patients. The nomogram prediction model, constructed based on age, race, stage, and treatment regimen, demonstrates accurate and effective predictive capabilities for prognostic factors in ENEC patients.

MO69-6 The possibility of microtubule-related agents as a new treatment option for neuroendocrine carcinoma and small cell lung cancer

MO69-6 The possibility of microtubule-related agents as a new treatment option for neuroendocrine carcinoma and small cell lung cancer

AKAP2-anchored protein phosphatase 1 controls prostatic neuroendocrine carcinoma cell migration and invasion

Prostate cancer (PC) is the second leading cause of cancer-related death in men. The growth of primary prostate cancer cells relies on circulating androgens and thus the standard therapy for the treatment of localized and advanced PC is the androgen deprivation therapy. Prostatic neuroendocrine carcinoma (PNEC) is an aggressive and highly metastatic subtype of prostate cancer, which displays poor prognosis and high lethality. Most of PNECs develop from prostate adenocarcinoma in response to androgen deprivation therapy, however the mechanisms involved in this transition and in the elevated biological aggressiveness of PNECs are poorly defined. Our current findings indicate that AKAP2 expression is dramatically upregulated in PNECs as compared to non-cancerous prostate tissues. Using a PNEC cell model, we could show that AKAP2 is localized both intracellularly and at the cell periphery where it colocalizes with F-actin. AKAP2 and F-actin interact directly through a newly identified actin-binding domain located on AKAP2. RNAi-mediated silencing of AKAP2 promotes the phosphorylation and deactivation of cofilin, a protein involved in actin turnover. This effect correlates with a significant reduction in cell migration and invasion. Co-immunoprecipitation experiments and proximity ligation assays revealed that AKAP2 forms a complex with the catalytic subunit of protein phosphatase 1 (PP1) in PNECs. Importantly, AKAP2-mediated anchoring of PP1 to the actin cytoskeleton regulates cofilin dephosphorylation and activation, which, in turn, enhances F-actin dynamics and favors migration and invasion. In conclusion, this study identified AKAP2 as an anchoring protein overexpressed in PNECs that controls cancer cell invasive properties by regulating cofilin phosphorylation.

LARGE NEUROENDOCRINE TUMOR IN A PATIENT WITH ACROMEGALY CASE REPORT.

The case of a patient with a rare malignancy whose incidence ranges from 0.2 to 2 / 100,000 individuals. The increase in incidence probably showed increasing changes in diagnosis. Approximately 25% of these tumors grow in the lungs and represent 2% of all lung tumors. Of all bronchial NETs, only 5% are associated with multiple type 1 endocrine neoplasms (MEN-1). According to the current WHO classification of 2015, neuroendocrine lung cancer should be classified into typical carcinoids, atypical carcinoids, large cell neuroendocrine carcinoma or small cell carcinoma, the classification being based on histological morphology. The commonly associated endocrine syndromes are inadequate secretion of the natriuretic hormone, Cushing's syndrome and, rarely, acromegaly. We report a case of a male patient with a large neuroendocrine tumor associated with a pituitary macroadenoma. Laboratory tests on admission were changed, GH of 56.5 ng / mL (Ref &lt;5 ng / mL), IGF-1 of 1304.4 ng / mL (Ref-96.4 - 227.8 ng / mL), chromogranin 4.89 (Ref 3.00), b-HCG-negative. The patient was initially submitted to thoracic surgery and subsequently underwent neurological surgery in another center, so that he was accompanied by professionals from various areas, making it increasingly evident the need for hospitals to have centers for the study of these neuroendocrine tumors.

Combined large cell neuroendocrine carcinoma, lung adenocarcinoma, and squamous cell carcinoma: a case report and review of the literature

BackgroundCombined large cell neuroendocrine carcinoma (C-LCNEC) has a poor prognosis and there is no consensus about the treatment regimen for both LCNEC and C-LCNEC patients.Case presentationThe patient was a 47-year-old female who received surgical resection. The postoperative histology and staging of the tumor suggested C-LCNEC with adenocarcinoma and squamous cell carcinoma and T2aN0M0 stage IB. Next-generation sequencing test showed KIF5B/RET fusion mutation without EGFR, ALK, RB1, and TP53 alterations. Adjuvant chemotherapy with 4-cycle docetaxel plus carboplatin was given and brain metastasis occurred after 10 months.ConclusionsC-LCNEC with adenocarcinoma and squamous cell carcinoma is rare and highly aggressive cancer. Surgical resection and adjuvant chemotherapy with SCLC regimen may improve the disease-free survival and overall survival. The accumulation of similar cases will clarify the profile and management of the disease.

Collision Tumour of Combined Neuroendocrine and Squamous Cell Carcinoma of Nasal Cavity and Paranasal Sinus- Case Report and Review of Literature.

There have been many disputes about the definition, diagnosis, therapy, and prognosis of collision tumours. We describe a rare patient with a collision tumour consisting of high-grade neuroendocrine carcinoma (NEC) and squamous cell carcinoma (SCC) in the right nasal cavity and paranasal sinus. She received surgery, concurrent chemoradiotherapy, and then two cycles of palliative chemotherapy. Follow-up at 26 months after diagnosis showed that this patient experienced a complete response with no signs of recurrence or metastasis. A literature review of previous 27 cases diagnosed with collision tumour of NEC and SCC in the head and neck was also undertaken. It is highly challenging to manage collision tumours because these are two morphologically and etiologically distinct tumours. Well-designed multimodality therapy including surgery and chemoradiotherapy might lead to a long survival in these patients.

Spontaneous histological transformation of lung squamous-cell carcinoma to large cell neuroendocrine carcinoma and small cell lung cancer.

Histopathological transformation between different types of lung cancer cells has been reported following a variety of anti-tumor treatments. Examples include transformation from lung adenocarcinoma to squamous-cell carcinoma (SCC) and transformation from non-small cell lung cancer (NSCLC) to small cell lung cancer (SCLC). A patient with intermittent hemoptysis for 2 days underwent a computed tomography (CT) scan that revealed interstitial pneumonia in addition to two enlarged paratracheal lymph nodes: one on the right (4R) and one on the left (4L) measuring 10 and 7mm in diameter, respectively (Fig. 1). There was no evidence of a lung or bronchial mass. Bronchoscopy identified an endoluminal primary mass in a superior segmental bronchus of the left lower lobe and pathological examination following surgery confirmed it to be SCC. At 15months post operation, a CT scan detected that the 4R lymph node had increased in size from 10 to 16mm in diameter. At the next follow-up 7 months later, a CT scan showed that the R4 lymph node had further increased in size from 16 to 40mm in the short axis, making it difficult for a surgeon to resect it "en bloc" immediately. The maximum standardized uptake value was 7.5 on PET-CT images. One month following completion of one cycle of neoadjuvant chemotherapy with gemcitabine and nedaplatin, a further CT scan indicated that the lymph node had decreased in size from 40 to 30mm in the short axis. A complete mediastinal lymphadenectomy via open thoracotomy was performed and the lymph node was resected. Histological examination identified a main large cell neuroendocrine carcinoma (LCNEC) component with a small fraction of small cell carcinoma, confirmed by immunohistochemical analysis and genetic evidence. Histopathological transformation from SCC to LCNEC with a small fraction of SCLC may have occurred spontaneously without any treatment.

First-in-human dose-escalation trial of BI 764532, a delta-like ligand 3 (DLL3)/CD3 IgG-like T-cell engager in patients (pts) with DLL3-positive (DLL3+) small-cell lung cancer (SCLC) and neuroendocrine carcinoma (NEC).

8502 Background: The inhibitory Notch ligand, DLL3, is highly expressed on the cell surface of SCLC and NEC tumors and is a promising drug target. BI 764532 is a DLL3/CD3 T cell engaging bispecific antibody that has shown potent preclinical anti-tumor activity in DLL3+ cells and xenograft models. NCT04429087 is an ongoing phase I first-in-human, open-label, dose-escalation trial of BI 764532 in adults with locally advanced/metastatic DLL3+ (confirmed centrally) SCLC, NEC or small cell carcinoma of any other origin (grouped as NEC), or large cell NEC (LCNEC). Methods: BI 764532 was administered intravenously using three different regimens: Regimen (R) A (fixed iv dose q3w); RB1 (fixed iv dose qw); RB2 (step-in doses followed by a fixed dose). Treatment (Tx) continued until progressive disease (PD), unacceptable toxicity, other withdrawal criteria, or maximum Tx duration (36 mos). The main objective was to determine the maximum tolerated dose (MTD) and/or recommended dose for expansion of BI 764532, based on dose-limiting toxicities (DLTs) during the MTD evaluation period. Further objectives were safety, tolerability, PK/PD and preliminary efficacy based on investigator review (RECIST v1.1). Results: As of 28th Dec 2022, 90 pts received ≥1 dose of BI 764532 (RA: n = 24, 8 dose levels; RB1: n = 10, 3 dose levels; RB2: n = 56, 6 dose levels; starting dose: 0.03 µg/kg). Median age: 60 years (32–78); ECOG PS 0/1: 24/74%; prior PD1/PD-L1 Tx: 40%; ≥2 prior lines of Tx: 69%. SCLC/NEC/LCNEC: 52/41/4%. Median Tx duration: 43 days (range 1–443); 25 pts are ongoing. DLTs were seen in 1 pt on RA (Grade 3 confusion) and 4 pts on RB2 (Grade 4 cytokine release syndrome [CRS]; Grade 3 CRS, Grade 3 nervous system disorder, Grade 2 infusion-related reaction). MTD has not been reached and dose escalation is ongoing. Overall, the most common treatment-related AEs were (any/Grade 3+): CRS (58/2%); pyrexia (19/0%); decreased lymphocytes (18/14%); asthenia (17/1%); dysgeusia (14/0%). CRS was managed with supportive care, corticosteroids, and/or anti-IL-6R antibodies. With RB2, most CRS and neurological events occurred early, and were reversable. Tumor response data were available for 70 pts (RA/RB1/RB2: n = 19/8/43). In pts with SCLC (n = 24) or NEC (n = 23) who received ≥ target dose of BI 764532, ORR was 33% and 22% across all regimens, respectively. One pt with LCNEC was also evaluable for response and achieved PR. Conclusions: BI 764532 showed clinically manageable tolerability and MTD has not been reached at the doses administered to date. Promising efficacy has been observed, not only in SCLC but also in difficult to treat entities such as NEC and LCNEC. The study is ongoing; updated data will be presented. Clinical trial information: NCT04429087 .

A tale of multiple primaries: Primary neuroendocrine carcinoma, vaginal vault and renal cell carcinoma in a 52 years old female

Cancer patients have 15-25% higher risk of second malignancy compared to general population. We hereby describe an extremely unusual case of 52-years-old-female with Neuroendocrine Carcinoma (NEC) of vaginal vault developing 4

Lung neuroendocrine neoplasms: a single centre surgical series and analysis of staging.

To review the outcomes of surgically resected lung neuroendocrine neoplasms (LNEN) at a tertiary referral centre and to validate a previously published LNEN-specific staging system (NETL). All patients who were identified on histopathology to have LNEN were included. Pre-, intra- and post-operative outcomes were collected, including long-term survival. Patients were staged by both the TNM (seventh and eighth edition) and NETL staging (seventh and eighth edition definitions). Kaplan-Meier (KM) survival analysis was performed according to histopathology and stage, along with uni- and multivariate analyses. A total of 132 patients were included in the study, with a median age of 65 years; 55% were female. Typical carcinoid (TC) was the most common pathology (53.4%) followed by large cell neuroendocrine carcinoma (LCNEC - 23.5%), atypical carcinoid (AC - 20.5%) and small cell carcinoma (3.0%). The most common operation performed was a lobectomy (55.3%). Overall survival at 5 years was 80% (100% TC, 78.2% AC, LCNEC 40.9%) and 5-year disease free survival was 76.8% (TC 94.3%, AC 56.8%, LCNEC 56.4%). KM curves showed a trend towards NETL performing better than TNM, however, in multivariate analysis only the histological subtype was found to be significant in our study. This is the largest known Australian series of LNEN to date, showing survival comparable to international outcomes. We have demonstrated large variations in outcome, driven by histological grade. The TNM system does not correlate with survival and we have not been able to show that currently proposed NETL staging is superior.

Incidence, survival comparison, and novel prognostic evaluation approaches for stage iii-iv pulmonary large cell neuroendocrine carcinoma and small cell lung cancer

BackgroundPulmonary large cell neuroendocrine carcinoma (LCNEC) and small cell lung cancer (SCLC) are two types of high-grade neuroendocrine carcinomas of the lung with poor prognosis. LCNEC has not been thoroughly studied due to its rarity, data are also lacking regarding the survival comparison and prognosis analysis of patients with locally advanced or metastatic LCNEC and SCLC.MethodsData of patients with LCNEC, SCLC, and other NSCLC who were diagnosed from 1975 to 2019 were extracted from the Surveillance, Epidemiology and End Results (SEER) database to estimate incidence. Those in stage III-IV and being diagnosed from 2010 to 2015 were utilized further to investigate their clinical characteristics and prognosis. Propensity score matching (PSM) analyses at a ratio of 1:2 was used to compare their survival outcomes. Nomograms of LCNEC and SCLC were established with internal validation, and the nomogram of SCLC was externally validated by 349 patients diagnosed in Cancer hospital, Chinese Academy of Medical Sciences & Peking Union Medical College from January 1, 2012 to December 31, 2018.ResultsThe incidence of LCNEC has been increasing in recent decades, meanwhile that of SCLC and other types of NSCLC were decreasing. A total of 91,635 lung cancer patients, including 785 with LCNEC, 15,776 with SCLC, and 75,074 with other NSCLC were enrolled for further analysis. The survival of stage III-IV LCNEC resembles that of SCLC, and significantly worse than other types of NSCLC before and after PSM analysis. In pretreatment prognostic analysis, age, T stage, N stage, M stage, bone metastasis, liver metastasis, and brain metastasis were found to be associated with the survival of both LCNEC and SCLC, besides sex, bilaterality, and lung metastasis were additional prognostic factors for SCLC. Two nomograms and convenient online tools respectively for LCNEC and SCLC were established accordingly with favorable predicting accuracy of < 1-year, < 2-year, < 3-year survival probabilities. In external validation of the SCLC nomogram with a Chinese cohort, the AUCs of 1-year, 2-year and 3-year ROC were 0.652, 0.669, and 0.750, respectively. All the results of 1-, 2-, 3- year variable-dependent ROC curves verified the superior prognostic value of our nomograms for LCNEC and SCLC over the traditional T/N/M staging system.ConclusionsBased on large sample-based cohort, we compared the epidemiological trends and survival outcomes between locally advanced or metastatic LCNEC, SCLC, and other NSCLC. Furthermore, two prognostic evaluation approaches respectively for LCNEC and SCLC might present as practical tools for clinicians to predict the survival outcome of these patients and facilitate risk stratification.

The Surgical Management of Lung Neuroendocrine Neoplasms.

This review summarizes key recent developments relevant to the surgical management of lung neuroendocrine neoplasms (L-NENs), including typical and atypical carcinoids, large cell neuroendocrine carcinoma, and small cell lung carcinoma. This review includes recent insights into the classification, clinical presentation, diagnostic workup, treatment options, and follow-up. Highlighted topics include general principles of surgery in localized or locally advanced or metastatic L-NENs, lung-sparing surgery for small, peripheral typical carcinoids, adjuvant and systemic therapies for typical and atypical carcinoids, and surgery and adjuvant therapies for large cell neuroendocrine carcinoma and small cell lung carcinoma.

Results of Primary Treatment and Salvage Treatment in the Management of Patients with Non-Squamous Cell Malignant Tumors of the Sinonasal Region: Single Institution Experience

Non-squamous cell carcinoma-related malignant sinonasal tract tumors (non-SCC MSTT) are rare and diverse malignancies. In this study, we report our experience in the management of this group of patients. The treatment outcome has been presented, involving both primary treatment and salvage approaches. Data from 61 patients treated radically due to non-SCC MSTT between 2000 and 2016 at the National Cancer Research Institute, Gliwice branch, were analyzed. The group consisted of the following pathological subtypes of MSTT: adenoid cystic carcinoma (ACC), undifferentiated sinonasal carcinoma (USC), sarcoma, olfactory neuroblastoma (ONB), adenocarcinoma, small cell neuroendocrine carcinoma (SNC), mucoepidermic carcinoma (MEC), and acinic cell carcinoma, which were found in nineteen (31%), seventeen (28%), seven (11.5%), seven (11.5%), five (8%), three (5%), two (3%) and one (2%) of patients, respectively. There were 28 (46%) males and 33 (54%) females at the median age of 51 years. Maxilla was the primary tumor localization followed by the nasal cavity and ethmoid sinus in thirty-one (51%), twenty (32.5%), and seven (11.5%) patients, respectively. In 46 (74%) patients, an advanced tumor stage (T3 or T4) was diagnosed. Primary nodal involvement (N) was found in three (5%) cases, and all patients underwent radical treatment. The combined treatment consisted of surgery and radiotherapy (RT) and was given to 52 (85%) patients. The probabilities of overall survival (OS), locoregional control (LRC), metastases-free survival (MFS), and disease-free survival (DFS) were assessed in pathological subtypes and grouped together, along with the ratio and effectiveness of salvage. Locoregional treatment failure was seen in 21 (34%) patients. Salvage treatment was performed in fifteen (71%) patients and was effective in nine (60%) cases. There was a significant difference in OS between patients who underwent salvage and those who did not (median: 40 months vs. 7 months, p = 0.01). In the group of patients who underwent salvage, OS was significantly longer when the procedure was effective (median: 80.5 months) than if it failed (median: 20.5 months), p < 0.0001. OS in patients after effective salvage was the same as in patients who were primary cured (median: 80.5 months vs. 88 months, p = 0.8). Distant metastases developed in ten (16%) patients. Five and ten year LRC, MFS, DFS, and OS were 69%, 83%, 60%, 70%, and 58%, 83%, 47%, 49%, respectively. The best treatment results were observed for patients with adenocarcinoma and sarcoma, while USC gave the poorest results in our set of patients. In this study, we indicate that salvage is possible in most patients with non-SCC MSTT with locoregional failure and that it may significantly prolong their overall survival.

Multi-center, retrospective study of first-line systemic therapy ± immune checkpoint inhibition for metastatic neuroendocrine carcinoma of the urinary tract.

467 Background: Neuroendocrine, small cell, or large cell carcinoma originating from the urothelium (uro-NE/SCC/LCC) is rare. Outcomes for metastatic disease are dismal. Treatment is extrapolated from small cell lung cancer, for which immune checkpoint inhibitors (ICIs) have modest activity. Preliminary activity has been reported with ICI for uro-NE. We aimed to compare real-world progression-free survival (PFS) and overall survival (OS) between ICI-containing and non-ICI-containing regimens in the first line (1L) metastatic setting for uro-NE/SCC/LCC. Methods: We performed a retrospective study at 11 cancer centers. Patients (pts) who received systemic therapy (2011-2021) for biopsy confirmed metastatic uro-NE/SCC/LCC were included. Pts with metastasis within 6 months of (neo)adjuvant chemotherapy (CT) (n=16) were excluded from 1L analyses. Results: 102 pts with metastatic uro-NE/SCC/LCC were evaluable. 17 (16.7%) had NE histology, 81 (79.4%) SCC, and 4 (3.9%) LCC. NE/SCC/LCC was mixed with urothelial histology in 19 (18.6%). Primary tumors were most often in the bladder (84.3%, n=86), less frequently upper tract (11.8%, n=12) or urethra (3.9%, n=4). 42 pts (41.2%) were previously treated for localized disease, the rest were de novo metastatic (n=60, 58.8%). Pts who received an ICI in any line (n=61) had significantly longer OS (p=0.038) than pts that never received an ICI (n=41). As shown in the table, in the 1L, ICI-containing regimens (n=33) resulted in significantly longer PFS, but not OS or ORR compared to non-ICI regimens (n=53). Subdividing 1L regimens into ICI without CT (n=14), CT without ICI (n=53), or ICI + CT (n=19), both PFS and OS were significantly different with similar ORR. ICI w/o CT had the longest median PFS and OS with an ORR 57.1% comparable to CT regimens. Of 61 pts that received ICI in any line, 14 (23.0%) had an immune-related adverse event of any grade; 11 (18.0%) received steroids. Conclusions: This is the largest ever report of ICI for metastatic uro-NE/SCC/LCC. ICIs were associated with improved outcomes with expected added toxicity. Further prospective investigation of ICI regimens is warranted. [Table: see text]

Long-Term Outcomes of Endoscopic Submucosal Dissection for Special Type of Esophageal Cancer

Background: Esophageal cancers other than two types, squamous cell carcinoma (SCC) and adenocarcinoma, are commonly referred to as special type of esophageal cancer (STEC). Studies on STECs have been limited because of its low prevalence. Therefore, we aimed to clarify the clinicopathological findings and the long-term outcomes of STECs that were managed with ESD. Methods: We reviewed 713 patients with 1,089 lesions who underwent ESD for primary esophageal cancer except Barrett’s esophageal cancer. Patients were classified into the SCC group and the STEC group, respectively. Their clinicopathological findings and long-term outcomes including disease-specific survival (DSS) were collected and examined. Results: A total of 19 consecutive patients (1.7%) were diagnosed with STEC. Nine patients were diagnosed with basaloid carcinoma, 6 with adenosquamous carcinoma, 2 with mucoepidermoid carcinoma, 2 with salivary duct-type carcinoma, and 1 with neuroendocrine cell carcinoma. There was significantly more pT1b esophageal cancer (47.4% vs. 11.0%, p < 0.01) and lymphovascular invasion (31.6% vs. 10.2%, p = 0.011) in the STEC group. Metastatic relapse and disease-specific mortality were significantly higher in the STEC group (both 15.8% vs. 1.2%, p < 0.01), and the STEC group had shorter DSS with 5-year DSS rates of 90.9%. In a subgroup analysis of patients with pT1a esophageal cancer, the 5-year DSS rate was shorter in the STEC group (p < 0.01). In the multivariate analysis, STEC (HR = 0.24) and tumor depth (HR = 12.60) were the factors associated with DSS. Conclusion: STECs are suggested to have high malignant potential and to be an independent negative prognostic factor for DSS.

P234 Differentiation of histopathological features between sporadic and colitis-associated colorectal cancer in a nationwide large cohort.

Abstract Background Colitis-associated colorectal cancer (CAC) can develop in patients with inflammatory bowel disease, and histological features differ between CAC and sporadic colorectal cancer (CRC). Moreover, advanced CAC has a poorer prognosis than sporadic CRC. Therefore, we compared histopathological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC. Methods We reviewed the clinical and histopathological data collected from 43 institutions, including surgery and gastroenterology departments, in the Japanese Society for Cancer of the Colon and Rectum between 1983 and 2020. Patient characteristics were compared between ulcerative colitis (UC), Crohn’s disease (CD), and sporadic CRC. Comparisons were performed by using all collected data or propensity score-matched data. Results A total of 1,077 patients with UC-CAC, 297 with CD-CAC, and 136,927 with sporadic CRC were included in all collected data. Although the prevalence of well or moderately differentiated adenocarcinoma (G1:well differentiated and G2:moderately differentiated) decreased according to tumor progression in all diseases (p&amp;lt;0.01, figure1), the prevalence of G3,G4, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, neuroendocrine carcinoma and squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histopathological findings other than G1 and G2 was also significantly higher in CAC (figure2,3). At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 (52.3%)) than in those with sporadic CRC (13/88 (14.8%)) (p&amp;lt;0.01). Conclusion Malignant potential is higher in CAC than in sporadic CRC according to tumor progression, which may lead to the poor prognosis of CAC.