Neoadjuvant chemotherapy improves the survival of patients with neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma of the stomach

Clinicopathologic characteristics and prognostic factors of pure gastric neuroendocrine carcinoma patients undergoing radical surgery

BACKGROUND

There is a low incidence of gastric neuroendocrine carcinoma (G-NEC), but it is associated with particularly aggressive biological behaviours and poor prognosis compared with other gastric neoplasms. Our study aimed to investigate the clinicopathologic traits and prognostic factors of patients with pure gastric neuroendocrine carcinoma treated with radical surgery.

METHODS

We retrospectively analysed 60 patients with pure G-NEC who underwent radical gastrectomy between March 2010 and May 2019. 68 patient who underwent curative surgery for mixed gastric adenoneuroendocrine carcinoma (G-ANEC) from August 2012 to June 2022. The relationships between the clinicopathologic characteristics of pure G-NEC and overall survival (OS) and disease-free survival (DFS), as well as the comparison of pure-NEC with G-ANEC in terms of prognosis and treatment regimens, were evaluated using the Kaplan-Meier method and (or) Cox regression.

RESULTS

The gastroesophageal junction (GEJ) was the predilection site for G-NEC. Tumor location, histology, and lymph node metastasis status were independent prognostic factors for OS (P < 0.05). Pathological T stage and the presence or absence of lymph node metastasis were independently associated variables with DFS (P = 0.019 and P = 0.041). Large cell neuroendocrine carcinoma (LCGNEC) did not differ statistically from the small cell neuroendocrine carcinoma (SCGNEC) (P = 0.314) for OS, while mixed type (MGNEC) vs. LCGNEC did differ significantly (P = 0.031). There were no significant differences in OS and DFS between etoposide and cisplatin (EP) and S-1 + oxaliplatin (SOX) / oxaliplatin + capecitabine (XELOX). The study of 106 patients found no significant impact of NEC proportion on OS (P = 0.438) or DFS (P = 0.079). Neoadjuvant/adjuvant chemotherapy targeting NEC versus adenocarcinoma showed no statistical difference in OS (P = 0.415, P = 0.350), but there was a trend toward longer survival with NEC-targeted regimen.

CONCLUSIONS

The LCGNEC did not differ statistically from the SCGNEC for OS, while the MGNEC vs. LCGNEC were different. The prognosis of G-NEC was related to the tumor location, histology, postoperative T stage, and lymph node metastasis. For gastric neuroendocrine carcinoma, prognosis does not differ statistically by NEC proportion. Chemotherapy regimens targeting lymph node metastases with an NEC component maybe better prognosis than those focusing on the adenocarcinoma component.

Prognostic significance of tertiary lymphoid structures in gastric neuroendocrine carcinoma with association to delta-like ligand 3 and neuroendocrine expressions

BACKGROUND

Gastric neuroendocrine carcinomas (NECs) are rare cancers with highly aggressive behavior. Although tertiary lymphoid structures (TLSs) are well-known prognostic factors in various cancers, their role in gastric NECs remain unexplored. Unique immunohistochemical subtypes of pulmonary NECs have been discovered, however, their feasibility in gastric NECs is unknown.

METHODS

The presence and maturation of TLSs (lymphoid aggregates, primary and secondary follicles) were assessed in 48 surgically resected gastric NECs and were compared with immunohistochemical subtypes, using a panel of ASCL1, NeuroD1, POU2F3, YAP1, and DLL3 with three neuroendocrine (NE) markers.

RESULTS

Patients with secondary follicles had significantly better overall survival (OS) and recurrence-free survival (RFS; both, p = 0.004) than those without them. Based on the hierarchical clustering, gastric NECs were classified into all low/negative (31%), high-YAP1 (19%), high-DLL3/low-NE (29%), and high-NE (21%) expression groups. The high-DLL3/low-NE group was associated with absent TLSs (p = 0.026) and showed the worst OS (p = 0.026). Distant metastasis and a lack of secondary follicles were poor independent prognostic factors of OS and RFS.

CONCLUSION

The assessment of TLSs is a feasible and potent biomarker for gastric NECs, thus enabling better prognosis and more effective immunotherapy. Furthermore, gastric NECs can be categorized as four immunohistochemically distinct groups, of which the high-DLL3/low-NE group has the worst OS with lack of TLSs.

Comparison of proximal and distal gastric neuroendocrine carcinoma based on SEER database

The occurrence of gastric neuroendocrine carcinoma (GNEC) is on the rise, and its prognosis is extremely poor. We compared survival outcomes between distal and proximal GNEC and developed a nomogram incorporating tumor site to enhance personalized management for patients with GNEC. 1807 patients were divided into DGNEC and PGNEC groups. We performed analyses by using propensity score matching (PSM) and Fine-Gray competing risk methods. A predictive nomogram for the prognosis of GNEC was constructed and validated. The cumulative incidence of cancer-specific death (CSD) in the DGNEC group was lower than that in the PGNEC group. Subgroup analysis showed lower CSD of DGNEC in males, females, tumor sizes (≤ 2 cm, 2 < tumor size ≤ 5 cm, > 5 cm, and unknown), grade stage I-II, and AJCC stage I-III, chemotherapy or no chemotherapy, surgery or no surgery groups (P < 0.05). Multivariate analysis revealed a significant association between PGNEC and CSD (HR, 1.4; 95% CI 1.13-1.73; P = 0.02). The independent predictors of CSD in patients with GNEC were primary site, gender, age, tumor size, AJCC stage, T stage, N stage, grade stage, and surgery. A predictive model based on multivariate analysis was constructed to estimate the probability of CSD at 1-, 3-, and 5-year. The calibration curves demonstrated excellent consistency between the predicted and observed probabilities of CSD. Patients with DGNEC have a better prognosis than those with PGNEC. The model exhibits strong predictive capability for these patients.

Synergizing traditional CT imaging with radiomics: a novel model for preoperative diagnosis of gastric neuroendocrine and mixed adenoneuroendocrine carcinoma

Objective

To develop diagnostic models for differentiating gastric neuroendocrine carcinoma (g-NEC) and gastric mixed adeno-neuroendocrine carcinoma (g-MANEC) from gastric adenocarcinoma (g-ADC) based on traditional contrast enhanced CT imaging features and radiomics features.

Methods

We retrospectively analyzed 90 g-(MA)NEC (g-MANEC and g-NEC) patients matched 1:1 by T-stage with 90 g-ADC patients. Traditional CT features were analyzed using univariable and multivariable logistic regression. Tumor segmentation and radiomics features extraction were performed with Slicer and PyRadiomics. Feature selection was conducted through univariable analysis, correlation analysis, LASSO, and multivariable stepwise logistic. The combined model incorporated clinical and radiomics predictors. Diagnostic performance was assessed with ROC curves and DeLong's test. The models' diagnostic efficacy was further validated in subgroup of g-NEC vs. g-ADC and g-MANEC vs. g-ADC cases.

Results

Tumor necrosis and lymph node metastasis were independent predictors for differentiating g-(MA)NEC from g-ADC (P < 0.05). The clinical model's AUC was 0.700 (training) and 0.667(validation). Five radiomics features were retained, with the radiomics model showing AUC of 0.809 (training) and 0.802 (validation). The combined model's AUCs were 0.853 (training) and 0.812 (validation), significantly outperforming the clinical model (P < 0.05). Subgroup analysis revealed that the combined model exhibited acceptable performance in differentiating g-NEC from g-ADC and g-MANEC from g-ADC, with AUC of 0.887 and 0.823 in the training cohort and 0.852 and 0.762 in the validation cohort.

Conclusion

A combined model based on traditional CT imaging and radiomic features provides a non-invasive and effective preoperative diagnostic method for differentiating g-(MA)NEC from g-ADC.

Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract

Mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) are a heterogeneous group of malignant neoplasms that can settle in the gastroenteropancreatic tract. They are composed of a neuroendocrine (NE) and a non-NE component in at least 30% of each tumour. The non-NE component can include different histological combinations of glandular, squamous, mucinous and sarcomatoid phenotypes, and one or both of the components can be low-or high grade malignant. Recent changes in the nomenclature of these neoplasms might lead to great deal of confusion, and the lack of specific clinical trials is the main reason why their management is difficult. The review aims to clarify the definition of MiNEN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available data. It would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that, due to their low incidence, will require long recruitment periods.

Gastric mixed neuroendocrine non-neuroendocrine neoplasms

The uncommon tumour known as gastric mixed neuroendocrine-non-neuroendocrine neoplasms (G-MiNENs) is made up of parts of neuroendocrine carcinoma and adenocarcinoma. The biological and clinical features are different from those of gastric adenocarcinoma. Their pathophysiology, diagnostic standards, and clinical behaviour have all been the subject of lengthy debates, and their nomenclature has undergone multiple changes. Its emergence has created new challenges in the classification and diagnosis of gastric tumours. This review will update information on the topic, covering molecular aspects, diagnostic criteria, treatment, and prognostic factor discovery. It will also provide a historical context that will aid in understanding the evolution of the idea and nomenclature of mixed gastric tumours. Additionally, it will provide the reader a thorough understanding of this difficult topic of cancer that is applicable to real-world situations.

Efficacy and safety of neoadjuvant therapy in gastroenteropancreatic neuroendocrine neoplasms: A systematic review and meta-analysis

OBJECTIVE

To determine the effectiveness and safety of neoadjuvant therapy in gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) and provide evidence-based suggestions for clinical treatment.

METHODS

The Cochrane Library, Embase, PubMed, and Web of Science were searched for articles published that analyzed the effectiveness and safety of GEP-NEN-targeted neoadjuvant therapy before March 2023. A confidence interval (CI) of 95%, a subgroup analysis, heterogeneity, and effect size (ES) were analyzed, and a meta-analysis of the literature was performed using the Stata BE17 software.

RESULTS

A total of 417 patients from 13 studies were included in this meta-analysis. The primary variables comprised the objective response rate (ORR), disease control rate (DCR), surgical resection rate, and R0 resection rate with ES values of 0.42 (95% CI: 0.25-0.60), 0.96 (95% CI: 0.93-0.99), 0.67 (95% CI: 0.50-0.84), and 0.60 (95% CI: 0.54-0.67), respectively. The secondary variables were the incidence rates of treatment-related adverse events (TRAEs), Grade 3 or higher TRAEs, and surgical complications with ES values of 0.29 (95% CI: -0.03-0.21), 0.13 (95% CI: -0.07-0.33), and 0.35 (95% CI: 0.27-0.44), respectively.

CONCLUSION

Neoadjuvant therapy is an effective and safe treatment method for GEP-NENs. However, further studies are required to determine the optimal regimen for this therapy in these tumors.

Management of Gastric Neuroendocrine Tumors: A Review

Gastric neuroendocrine tumors (G-NET) are rare tumors arising from enterochromaffin-like cells of the gastric mucosa. They belong to a larger group called gastroenteropancreatic neuroendocrine tumors and are classified as low, intermediate, or high-grade tumors based on their proliferative indices. They are further categorized into three subtypes based on their morphologic characteristics, pathogenesis, and behavior. Types 1 and 2 tumors are characterized by elevated serum gastrin and are usually multifocal. They typically occur in the setting of atrophic gastritis or MEN1/Zollinger Ellison syndrome, respectively. Type 2 tumors are associated with the most symptoms, such as abdominal pain and diarrhea. Type 3 tumors are associated with normal serum gastrin, are usually solitary, and occur sporadically. This type has the most aggressive phenotype and metastatic potential. Treatment and prognosis for G-NET is dependent on their type, size, and stage. Type 1 has the best prognosis, and Type 3 has the worst. This review discusses the presentation, workup, and surgical management of these tumors.

Clinicopathological characteristics of gastric neuroendocrine neoplasms: A comprehensive analysis

OBJECTIVE

This study aimed to explore the clinicopathological characteristics and prognostic implications of gastric neuroendocrine neoplasms (g-NENs).

METHODS

A retrospective enrollment of 142 patients diagnosed with g-NENs was conducted at Zhejiang Cancer Hospital between January 1, 2007 and December 31, 2021. The study compared essential clinicopathological features and survival rates. Additionally, the prognosis of gastric neuroendocrine carcinomas/mixed neuroendocrine-non-neuroendocrine neoplasms (g-NEC/MiNEN) were contrasted with those of gastric adenocarcinoma (GAC) and signet ring cell carcinoma (SRCC).

RESULTS

The study comprised a total of 142 g-NENs cases, with a male-to-female ratio of approximately 2:1. The 5-year survival rates for g-NEC and g-MiNEN were 26.7% and 35.2%, respectively. Corresponding 5-year survival rates for G1 and G2 were observed at 100% and 80.0%, respectively. g-NEC/MiNEN showed a significantly worse prognosis compared to g-NET (p < 0.001). g-NEC/MiNEN exhibited a poor prognosis compared to GAC (p < 0.001), and within poorly differentiated GAC, g-NEC/MiNEN demonstrated a worse prognosis (p = 0.007). Additionally, patients receiving postoperative adjuvant therapy exhibited notably prolonged overall survival (OS) in the case of g-NEC/MiNEN (p = 0.010).

CONCLUSION

In short, the prognosis of g-NEC/MiNEN was worse than that of g-NET, GAC and poorly differentiated GAC, but this group benefit from postoperative adjuvant therapy.

Comparison of survival outcomes and survival prediction in patients with primary colorectal MANEC and primary colorectal SRCC: a population-based propensity-score matching study

PURPOSE

Primary mixed adeno-neuroendocrine carcinoma (MANEC) and primary signet-ring cell cancer (SRCC) are two rare but highly malignant tumors in colorectal cancer. Therefore, we attempted to compare the tumors' survival outcomes, identify risk factors, and ultimately evaluate the prognosis by developing a nomogram.

METHODS

We identified 755 MANEC and 5836 SRCC patients of colorectal cancer. PSM was used to balance the influence of baseline clinical and pathological differences. Kaplan-Meier method was used to compare the prognosis of different pathological grades and AJCC stages. Cox proportional hazards model was used to identify potential prognostic factors for the two groups. Finally, we developed a nomogram and evaluated the feasibility of the model.

RESULTS

After PSM, the median OS and CSS of MANEC patients were significantly better than those of SRCC patients in stage III-IV (P < 0.001) but similar in stage I-II. The median OS and CSS of MANEC patients in each pathological grade were also greater than those of SRCC patients. Patients with MANEC and SRCC who underwent lymph node dissection in more than four areas had longer survival time. MANEC patients benefited from postoperative chemotherapy and radiotherapy; among SRCC patients, those who received preoperative and postoperative comprehensive chemotherapy and radiotherapy had benefits in OS and CSS.

CONCLUSION

Both MANEC and SRCC are often diagnosed in advanced stages, highlighting the importance of early screening. Despite the better prognosis of MANEC compared to SRCC, both types of patients require the formulation of personalized treatment strategies based on different risk factors combined with column charts.

Equivalent Survival between Gastric Large-Cell Neuroendocrine Carcinoma and Gastric Small-Cell Neuroendocrine Carcinoma

BACKGROUND

According to the 2019 World Health Organization (WHO) classification of gastric neuroendocrine neoplasms, gastric neuroendocrine carcinoma (GNEC) can be further divided into gastric large-cell neuroendocrine carcinoma (GLNEC) and gastric small-cell neuroendocrine carcinoma (GSNEC). Whether the prognoses of the two types have a discrepancy has long been disputed.

METHOD

We collected patients diagnosed with GLNEC or GSNEC in the National Cancer Center of China between January 2000 and December 2020. The characteristics and survival outcomes were compared between the two groups. We further verified our conclusion using the SEER dataset.

RESULTS

A total of 114 GNEC patients, including 82 patients with GLNEC and 32 patients with GSNEC, have completed treatment in our hospital. Clinicopathologic differences were not observed between patients with GSNEC and GLNEC concerning the sex, age, body mass index, Charlson Comorbidity Index, tumor location, tumor size, stage, treatment received, the expression of neuroendocrine markers (CD56, Chromogranin A, synaptophysin), and score on the Ki-67 index. The 1-year, 3-year, and 5-year overall survival rates of GLNEC and GSNEC were 89.0%, 60.5%, and 52.4%, and 93.8%, 56.3%, and 52.7%, which showed no statistically significant differences. This result was confirmed further by using the SEER dataset after the inverse probability of treatment weighting.

CONCLUSIONS

Although with different cell morphology, the comparison of prognosis between the GLNEC and GSNEC has no significant statistical difference.

Digestive MiNENs: Could histological classification and molecular characterization drive clinical outcome and therapeutic approach?

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are epithelial neoplasms in which neuroendocrine and non-neuroendocrine discrete components are combined, each of which constitutes ≥ 30% of the neoplasm. The finding of an additional neuroendocrine component seems to characterize the tumor's biological behavior. Few studies have proved MiNENs histogenetic and molecular characterization, and the development of molecular markers for more accurate classification of MiNENs represents a clinical need. However, a common origin of the neuroendocrine and non-neuroendocrine components from a pluripotent cancer stem cell could be suggested. The optimal clinical management of MiNENS is largely unknown. Whenever feasible, curative-intent resection should be performed for localized disease; in advanced disease, the treatment should be targeted to the component responsible for the metastatic spreading. This paper provides a revision of the current knowledge on MiNENs, focusing on available evidence about their molecular characterization to suggest a prognostic stratification of these rare forms.

European Neuroendocrine Tumor Society (ENETS) 2023 guidance paper for digestive neuroendocrine carcinoma

This ENETS guidance paper, developed by a multidisciplinary working group, provides up-to-date and practical advice on the diagnosis and management of digestive neuroendocrine carcinoma, based on recent developments and study results. These recommendations aim to pave the road for more standardized care for our patients resulting in improved outcomes. Prognosis is generally poor for digestive NEC, most are advanced at diagnosis and median survival in metastatic disease is 11-12 months. Surgery can be of benefit for localized disease after extensive preoperative imaging. Carboplatin in combination with etoposide is recommended as first-line treatment for metastatic disease. Irinotecan with fluoropyrimidines has the best evidence as second-line treatment. Immunotherapy plays a minor role in biomarker-unselected patients. Molecular profiling if available is encouraged to identify new targets. More prospective clinical trials are highly needed to fulfil the unmet needs in this field, especially on new predictive and prognostic biomarkers and to improve survival of patients with advanced disease.

Mixed large and small cell neuroendocrine carcinoma of the stomach: A case report and review of literature

BACKGROUND

Gastric neuroendocrine carcinoma (GNEC) is a rare histological subtype of gastric cancer, which is categorized into small cell and large cell neuroendocrine carcinomas. It is characterized by strong invasiveness and poor prognosis. Mixed large and small cell neuroendocrine carcinoma (L/SCNEC) is an extremely rare pathological type of gastric cancer, and there have been no reports on this situation until now.

CASE SUMMARY

Herein, we first present a 57-year-old patient diagnosed with L/SCNEC of the stomach. A 57-year-old Chinese male presented with epigastric discomfort. Outpatient gastroscopic biopsy was performed, and pathological examination revealed that the cardia was invaded by adenocarcinoma. The patient underwent laparoscopic-assisted radical proximal subtotal gastrectomy and was diagnosed with L/SCNEC. He refused adjuvant treatment and was followed up every 3 mo. Eight months after the operation, the patient showed no evidence of local recurrence or distant metastasis.

CONCLUSION

We advocate conducting further genomic studies to explore the origin of gastric large cell and small cell neuroendocrine carcinoma and using different chemotherapy schemes according to large or small cell neuroendocrine carcinoma of the stomach for clinical research to clarify the heterogeneity of GNEC and improve the prognosis of patients with GNEC.

Long-term surgical outcomes of gastric neuroendocrine carcinoma and mixed neuroendocrine-non-neuroendocrine neoplasms

Background

Neuroendocrine carcinoma (NEC) and mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) are extremely rare subtypes of gastric cancer. MiNEN is a mix of carcinomatous components and neuroendocrine neoplasm in the same lesion. NEC and MiNEN have a poor prognosis, are difficult to diagnose, and have no established treatment. Herein, we assessed the clinicopathological characteristics and long-term surgical outcomes of gastric NEC and MiNEN patients in our hospital.

Methods

We retrospectively assessed 1538 patients pathologically diagnosed with gastric cancer and who underwent curative surgical resection at our institution between January 1999 and October 2021. Of these patients, 25 (1.6%) were pathologically diagnosed with neuroendocrine neoplasms. From these 25 patients, we retrospectively analyzed the clinicopathological characteristics and surgical outcomes of 13 (0.8%) patients pathologically diagnosed with NEC or MiNEN.

Results

The NEC and MiNEN patients consisted of 11 men and 2 women [mean age, 74 (62–84) years]. The preoperative histological diagnoses were NEC (n = 4) and adenocarcinoma (n = 9). The final pathological diagnoses were large cell neuroendocrine carcinoma (LCNEC; n = 7) and MiNEN (n = 6). Total gastrectomy was the most common surgical procedure (9/13, 69.2%), followed by distal gastrectomy (3/13, 23.1%) and proximal gastrectomy (1/13, 7.7%). Immunohistochemical staining showed 8 CD56-positive patients. All 13 patients were positive for chromogranin A and synaptophysin. The mean Ki-67 value was 64.8 (0–95)%, and the mean mitotic score was 107.9 (0–400). Nine patients survived without recurrence postresection. The median postresection overall survival time was 68.7 (8.0–129) months. The 5-year survival rate was 0.75 ([95% CI] 0.408–0.912).

Conclusion

The surgical treatment outcomes of NEC and MiNEN patients were relatively favorable. Although evidence concerning the effectiveness of surgery alone is meager, radical resection as part of multidisciplinary treatment including chemotherapy can potentially improve prognosis.

Successful Neoadjuvant Chemotherapy for Small-Cell Neuroendocrine Carcinoma of the Pancreas: A Case Report

Neoadjuvant therapy for pancreatic neuroendocrine tumors may potentially aid downstaging, increase the possibility of radical surgery. We herein report a case of a 63-year-old man who had been diagnosed with locally advanced small-cell neuroendocrine carcinomas of the pancreas according to the diagnostic biopsy. The patient received 6 courses of etoposide and cisplatin as neoadjuvant therapy in an attempt to stop tumor progression, which promoted obvious tumor shrinkage without adverse effects and allowed subsequent Appleby procedure, the distal pancreatectomy with celiac artery resection. The patient showed no recurrence in the follow-up of a contrast-enhanced computed tomographic scan, which is 8 months after surgery. To the best of our knowledge, this is a rare case to report etoposide and cisplatin administration before surgery for unresectable pancreatic neuroendocrine carcinoma promoted a pathological partial response and finally achieved a radical surgery, providing a novel therapeutic option for patients with locally advanced pancreatic neuroendocrine carcinoma.

Neoadjuvant and Adjuvant Chemotherapeutic Strategy of Colorectal Mixed Adeno-Neuroendocrine Carcinomas

Mixed adeno-neuroendocrine carcinomas (MANEC) is a rare pathological diagnosis characterized by the presence of both adeno-carcinomatous and neuroendocrine differentiation with each component comprising 30% of the tumor. This literature review is aimed at the extraction of all existing clinical studies and reviews on colorectal MANEC so as to ensure that a suitable chemotherapeutic regimen is chosen to improve survival outcomes and prognosis of the disease. Parallel search strategies were employed to extract past 10 years articles from PubMed, PubMed Central and Google Scholar databases. A total of 30 records consisting of one clinical trial, five retrospective cohort studies, one case control study, one case series, 16 case reports and six review papers were shortlisted. Chemotherapeutic regimens that were administered as an adjuvant and a neoadjuvant therapy were analyzed with their survival outcomes. The overall survival rate of those administered with neoadjuvant and adjuvant therapy can be as high as 57.4% and 69%, respectively. Multiple chemotherapeutic regimens were employed in colorectal MANEC and superiority of one regimen over the other can’t be established. Any drug or combination of drugs that is responsive against either of the MANEC components is found to be effective against the tumor. However, excellent responsiveness has been found with 5-fluorouracil regimens as a neoadjuvant therapy and platinum-based combinations as an adjuvant therapy. XELOX, streptozocin and S1 regimens also prove to be drugs of choice in aggressive and metastasized disease conditions. Our analysis allows for improved chemotherapeutic management of individuals with colorectal MANEC and establishes an increased potential for use of streptozocin therapy in the clinical setting. However, newer drugs like amrubicin require further research prior to describing its efficacy in colorectal MANEC.

Gastric Mixed Neuroendocrine Non-Neuroendocrine Neoplasms: A Western Center Case Series

BACKGROUND

Mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) represent a rare tumor composed of adenocarcinoma and neuroendocrine carcinoma components. This study reports a case series of gastric MiNEN and discusses issues related to its diagnosis, management, and outcomes.

METHODS

We retrospectively analyzed data from patients with gastric MiNEN who underwent surgical resection at our service from 2009 to 2020. Patients with gastric adenocarcinoma served as a comparison group. Clinical, pathologic, and surgical characteristics were compared.

RESULTS

During the selected period, 5 gastric MiNEN patients and 597 patients with gastric adenocarcinoma were included. Among the clinical variables, age, sex, BMI, and laboratory exams were similar between the two groups. Only ASA classification was different (p = 0.015). Pathological variables such as tumor size, lymphovascular invasion, number of retrieved lymph nodes, and pTNM staging were also similar between both groups. Lastly, early surgical outcomes and long-term survival did not differ between gastric MiNEN and adenocarcinoma patients.

CONCLUSION

A MiNEN is a rare tumor that represents less than 1% of GC patients undergoing curative treatment, and demonstrated clinicopathological characteristics and outcomes similar to gastric adenocarcinoma.

Comparison of neoadjuvant chemotherapy followed by surgery vs. surgery alone for locally advanced gastric cancer: a meta-analysis

BACKGROUND

The neoadjuvant chemotherapy is increasingly used in advanced gastric cancer, but the effects on safety and survival are still controversial. The objective of this meta-analysis was to compare the overall survival and short-term surgical outcomes between neoadjuvant chemotherapy followed by surgery (NACS) and surgery alone (SA) for locally advanced gastric cancer.

METHODS

Databases (PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar) were explored for relative studies from January 2000 to January 2021. The quality of randomized controlled trials and cohort studies was evaluated using the modified Jadad scoring system and the Newcastle-Ottawa scale, respectively. The Review Manager software (version 5.3) was used to perform this meta-analysis. The overall survival was evaluated as the primary outcome, while perioperative indicators and post-operative complications were evaluated as the secondary outcomes.

RESULTS

Twenty studies, including 1420 NACS cases and 1942 SA cases, were enrolled. The results showed that there were no significant differences in overall survival (P = 0.240), harvested lymph nodes (P = 0.200), total complications (P = 0.080), and 30-day post-operative mortality (P = 0.490) between the NACS and SA groups. However, the NACS group was associated with a longer operation time (P < 0.0001), a higher R0 resection rate (P = 0.003), less reoperation (P = 0.030), and less anastomotic leakage (P = 0.007) compared with SA group.

CONCLUSIONS

Compared with SA, NACS was considered safe and feasible for improved R0 resection rate as well as decreased reoperation and anastomotic leakage. While unbenefited overall survival indicated a less important effect of NACS on long-term oncological outcomes.

Clinicopathological characteristics and prognosis of 232 patients with poorly differentiated gastric neuroendocrine neoplasms

BACKGROUND

Poorly differentiated gastric neuroendocrine neoplasms (PDGNENs) include gastric neuroendocrine carcinoma (NEC) and mixed adenoneuroendocrine carcinoma, which are highly malignant and rare tumors, and their incidence has increased over the past few decades. However, the clinicopathological features and outcomes of patients with PDGNENs have not been completely elucidated.

AIM

To investigate the clinicopathological characteristics and prognostic factors of patients with PDGNENs.

METHODS

The data from seven centers in China from March 2007 to November 2019 were analyzed retrospectively.

RESULTS

Among the 232 patients with PDGNENs, 191 (82.3%) were male, with an average age of 62.83 ± 9.11 years. One hundred and thirteen (49.34%) of 229 patients had a stage III disease and 86 (37.55%) had stage IV disease. Three (1.58%) of 190 patients had no clinical symptoms, while 187 (98.42%) patients presented clinical symptoms. The tumors were mainly (89.17%) solitary and located in the upper third of the stomach (cardia and fundus of stomach: 115/215, 53.49%). Most lesions were ulcers (157/232, 67.67%), with an average diameter of 4.66 ± 2.77 cm. In terms of tumor invasion, the majority of tumors invaded the serosa (116/198, 58.58%). The median survival time of the 232 patients was 13.50 mo (7, 31 mo), and the overall 1-year, 3-year, and 5-year survival rates were 49%, 19%, and 5%, respectively. According to univariate analysis, tumor number, tumor diameter, gastric invasion status, American Joint Committee on Cancer (AJCC) stage, and distant metastasis status were prognostic factors for patients with PDGNENs. Multivariate analysis showed that tumor number, tumor diameter, AJCC stage, and distant metastasis status were independent prognostic factors for patients with PDGNENs.

CONCLUSION

The overall prognosis of patients with PDGNENs is poor. The outcomes of patients with a tumor diameter > 5 cm, multiple tumors, and stage IV tumors are worse than those of other patients.

Secondary Nasopharyngeal Mixed Adenoneuroendocrine Carcinoma After Radical Radiotherapy for Nasopharyngeal Carcinoma: A Rare Case and Literature Review

The incidence of primary mixed adenoneuroendocrine carcinoma (MANEC) is rapidly increasing. MANEC mainly arises from the gastrointestinal tract, but occasionally it occurs as a pathological type of second primary malignancy (SPM). These SPMs can occur in the nasopharynx. Herein we describe the case of a first secondary nasopharyngeal MANEC that was detected 20 years after radical radiotherapy for nasopharyngeal carcinoma. The patient was a 50-year-old man who was admitted to our hospital after experiencing 1 month of left nasal congestion and ipsilateral tinnitus caused by a nasopharyngeal mass that was detected via physical examination and magnetic resonance imaging. A biopsy specimen from this nasopharyngeal lesion led to a histopathological diagnosis of recurrent nasopharyngeal carcinoma. He underwent high-dose palliative radiotherapy, followed by a course of gemcitabine–cisplatin-based adjuvant chemotherapy. These treatments failed to achieve local control of the tumor, and progressive left earache emerged. Another two forceps biopsies of the external auditory canal mass were conducted, and immunohistochemical testing for adenocarcinoma and neuroendocrine carcinoma markers including CK7, CK8, CK18, carcinoembryonic antigen, synaptophysin, chromogranin A, and CD56 was conducted. The diagnosis of MANEC was ultimately confirmed 5 months after the first visit, and one additional cycle of chemotherapy was subsequently performed. The patient died of hepatic metastases 8 months after the final diagnosis. Knowledge of this rare case will raise awareness of MANEC as a new pathological type of SPM originating in the nasopharynx, which will reduce delays and promote early diagnosis.

Clinicopathological features and prognostic factors associated with gastroenteropancreatic mixed neuroendocrine non-neuroendocrine neoplasms in Chinese patients

BACKGROUND

The incidence of mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) is low. To improve our understanding of this rare tumor type and optimally guide clinical treatment, associated risk factors, clinical manifestations, and prognosis must be explored.

AIM

To identify risk factors that influence the prognosis of patients with gastroenteropancreatic MiNEN (GEP-MiNEN).

METHODS

We retrospectively analyzed the clinical data of 46 patients who were diagnosed with GEP-MiNEN at the First Affiliated Hospital of Bengbu Medical College (Anhui, China) between January 2013 and December 2017. Risk factors influencing the prognosis of the patients were assessed using Kaplan-Meier curves and cox regression models. We compared the results with 55 randomly selected patients with gastroenteropancreatic GEP neuroendocrine tumors, 47 with neuroendocrine carcinomas (NEC), and 58 with poorly differentiated adenocarcinoma.

RESULTS

Among the 46 patients with GEP-MiNEN, thirty-five had gastric tumors, nine had intestinal tumors (four in the small intestine and five in the colon and rectum), and two had pancreatic tumors. The median age of the patients was 66 (41-84) years, and the male-to-female ratio was 2.83. Thirty-three (71.7%) patients had clinical stage III and IV cancers. Distant metastasis occurred in 14 patients, of which 13 had metastasis to the liver. The follow-up period was 11-72 mo, and the median overall survival was 30 mo. Ki-67 index ≥ 50%, high proportion of NEC, lymph node involvement, distant metastasis, and higher clinical stage were independent risk factors affecting the prognosis of patients with GEP-MiNEN. The median overall survival was shorter for patients with NEC than for those with MiNEN (14 mo vs 30 mo, P = 0.001), but did not significantly differ from those with poorly differentiated adenocarcinoma and MiNEN (30 mo vs 18 mo, P = 0.453).

CONCLUSION

A poor prognosis is associated with rare, aggressive GEP-MiNEN. Ki-67 index, tumor composition, lymph node involvement, distant metastasis, and clinical stage are important factors for patient prognosis.

Prognostic signature of lung adenocarcinoma based on stem cell-related genes

Lung adenocarcinoma (LUAD) is characterized by high infiltration and rapid growth. The function of the stem cell population is to control and maintain cell regeneration. Therefore, it is necessary to study the prognostic value of stem cell-related genes in LUAD. Signature genes were screened out from 166 stem cell-related genes according to the least absolute shrinkage operator (LASSO) and subsequently multivariate Cox regression analysis, and then established risk model. Immune infiltration and nomogram model were used to evaluate the clinical efficacy of signature. A signature consisting of 10 genes was used to dichotomize the LUAD patients into two groups (cutoff, 1.314), and then validated in GSE20319 and GSE42127. There was a significant correlation between signature and clinical characteristics. Patients with high-risk had a shorter overall survival. Furthermore, significant differences were found in multiple immune cells between the high-risk group and low-risk group. A high correlation was also reflected between signature and immune infiltration. What’s more, the signature could effectively predict the efficacy of chemotherapy in patients with LUAD, and a nomogram based on signature might accurately predict the prognosis of patients with LUAD. The signature-based of stem cell-related genes might be contributed to predicting prognosis of patients with LUAD.

A Retrospective Study of Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer

Objective

To explore the efficacy and safety of neoadjuvant chemotherapy in the doublet and triplet regimens of locally advanced gastric cancer.

Patients and Methods

A retrospective analysis was conducted on 162 patients with gastric cancer who received neoadjuvant chemotherapy, including 74 patients receiving doublet regimen (fluorouracil/platinum) and 88 patients receiving triplet regimen (fluorouracil/platinum/Taxol). Patients in both groups received neoadjuvant chemotherapy for two cycles, and underwent surgical resection 4 weeks after the end of chemotherapy.

Results

The total clinical remission rate was 68.6% (105/153), the phase-down rate was 46.4% (71/153), and the pathological response rate was 59.9% (97/162). In the doublet and triplet regimen, the clinical remission rate was 65.7% (44/67) and 70.9% (61/86) (P = 0.708), the descending period rate was 41.8% (28/67) and 50.0% (43/86) (P = 0.485), and the pathological response rate was 51.4% (38/74) and 67.0% (59/88) (P = 0.190). The median disease-free survival (DFS) and overall survival (OS) of 162 patients were 36.0 and 58.5 months. In the doublet and triplet regimen, the median DFS was 38.0 and 34.0 months (P = 0.377), and the median OS was 59.0 and 56.5 months (P = 0.256). The side effects of the doublet group were significantly lower than those of the triplet group, with leucopenia rate of 45.9% (34/74) and 62.5% (55/88) (P = 0.035); thrombocytopenia rate of 18.9% (14/74) and 35.2% (31/88) (P = 0.021); nausea rate of 45.9% (34/74) and 64.8% (57/88) (P = 0.016), and diarrhea rate of 1.4% (1/74) and 9.1% (8/88) (P = 0.032).

Conclusion

Neoadjuvant chemotherapy is safe and effective for locally advanced gastric cancer. The clinical efficacy of neoadjuvant chemotherapy in the doublet group and the triplet group is equivalent, and the doublet group has better safety and tolerance.

Comparison of overall survival of gastric neoplasms containing neuroendocrine carcinoma components with gastric adenocarcinoma: a propensity score matching study

BACKGROUND

Gastric neoplasms containing neuroendocrine carcinoma (NEC) components are rare malignancies with highly aggressive behavior and a poor prognosis and include pure NEC and mixed tumors containing NEC components. We aimed to investigate whether there is a distinct difference in overall survival (OS) between gastric neoplasms containing NEC components and gastric adenocarcinoma.

METHODS

Surgically resected gastric neoplasms containing NEC components (n = 180) and gastric adenocarcinomas (n = 785) from January 2013 to December 2019 at Peking University Cancer Hospital were retrospectively analysed. Patients were categorized into a surgical group and a neoadjuvant group and adjusted using propensity score matching. In the two groups, gastric neoplasms containing NEC components were divided into pure NEC and mixed tumors with less than 30% (< 30% G-HMiNEN), between 30 and 70% (G-HMiNEN) and more than 70% (> 70% G-HMiNEN) neuroendocrine carcinoma components. OS was compared between these groups and the gastric adenocarcinoma group.

RESULTS

The OS of gastric neoplasms containing neuroendocrine NEC components was poorer than that of gastric adenocarcinomas in the surgical group, regardless of whether the percentage of neuroendocrine cancer components was less than 30%, between 30 and 70%, more than 70% or 100%. Cox multivariable regression analysis suggested that tumor category (neoplasms containing NEC components or gastric adenocarcinoma) was an independent risk factor for prognosis. Interestingly, among patients receiving neoadjuvant therapy, the difference was not significant.

CONCLUSIONS

Gastric neoplasms containing any proportion of NEC components had poorer overall survival than gastric adenocarcinoma in patients treated with surgery directly, indicating that these neoplasms are more malignant than gastric adenocarcinoma. Among the patients receiving neoadjuvant therapy, the difference in overall survival was not significant, which was in sharp contrast with the results of the surgery group, suggesting that neoadjuvant therapy may have a good effect in the treatment of these neoplasms.