Clinicopathological hallmarks and biomarkers of colorectal neuroendocrine neoplasms

LncRNA PCAT6 promotes progression and metastasis of colonic neuroendocrine carcinoma via MAPK pathway

BACKGROUND

Colonic neuroendocrine carcinomas (NECs) are highly malignant and invasive with poor prognosis. Long noncoding RNAs (LncRNAs) participate in the tumorigenesis and metastasis of multiple cancers.

AIM

To detect the roles and mechanisms of lncRNA prostate cancer associated transcript 6 (PCAT6) in the progression of colonic NEC.

METHODS

Human NEC and adjacent normal samples were collected for immunohistochemistry staining of CgA and real-time quantitative polymerase chain reaction (RT-qPCR) of PCAT6 mRNA level. Subcutaneous xenograft tumor model and lung metastasis model were established in nude mice. The lung tissues were stained by hematoxylin and eosin to assess pulmonary metastasis. The expression of epithelial-mesenchymal transition (EMT)-related markers and pathway-related genes was measured by RT-qPCR and western blotting. CD56 expression was assessed by immunofluorescence staining. The biological functions of PCAT6 were examined by cell counting kit-8, colony formation assays, Transwell assays and wound healing assays. The interaction between PCAT6 and its potential downstream target was verified by luciferase reporter assays.

RESULTS

LncRNA PCAT6 was upregulated in human NEC samples and LCC-18 cells, and its high expression was positively correlated with poor prognosis in patients with colonic NEC. Additionally, the expression of PCAT6 was positively associated with the proliferation, migration, invasion, and EMT of LCC-18 cells. Moreover, PCAT6 facilitated tumor growth, lung metastasis and EMT in xenografts. Mechanistically, PCAT6 promoted the activation of MAPK to enhance the EMT in colonic NEC by targeting miR-326.

CONCLUSION

In conclusion, lncRNA PCAT6 accelerates the process of colonic NEC by activating ERK/p38 MAPK signaling through targeting miR-326. These results might provide useful information for exploring the potential therapeutic targets in colonic NEC.

Predictive and prognostic nomogram models for liver metastasis in colorectal neuroendocrine neoplasms: a large population study

Background

In recent years, the incidence of patients with colorectal neuroendocrine neoplasms (CRNENs) has been continuously increasing. When diagnosed, most patients have distant metastases. Liver metastasis (LM) is the most common type of distant metastasis, and the prognosis is poor once it occurs. However, there is still a lack of large studies on the risk and prognosis of LM in CRNENs. This study aims to identify factors related to LM and prognosis and to develop a predictive model accordingly.

Methods

In this study, the Surveillance, Epidemiology, and End Results (SEER) database was used to collect clinical data from patients with CRNENs. The logistic regression analyses were conducted to identify factors associated with LM in patients with CRNENs. The patients with LM formed the prognostic cohort, and Cox regression analyses were performed to evaluate prognostic factors in patients with liver metastasis of colorectal neuroendocrine neoplasms (LM-CRNENs). Predictive and prognostic nomogram models were constructed based on the multivariate logistic and Cox analysis results. Finally, the capabilities of the nomogram models were verified through model assessment metrics, including the receiver operating characteristic (ROC) curves, calibration curve, and decision curve analysis (DCA) curve.

Results

This study ultimately encompassed a total of 10,260 patients with CRNENs. Among these patients, 501 cases developed LM. The result of multivariate logistic regression analyses indicated that histologic type, tumor grade, T stage, N stage, lung metastasis, bone metastasis, and tumor size were independent predictive factors for LM in patients with CRNENs (p < 0.05). Multivariate Cox regression analyses indicated that age, primary tumor site, histologic type, tumor grade, N stage, tumor size, chemotherapy, and surgery were independent prognostic factors (p < 0.05) for patients with LM-CRNENs. The predictive and prognostic nomogram models were established based on the independent factors of logistic and Cox analyses. The nomogram models can provide higher accuracy and efficacy in predicting the probability of LM in patients with CRNENs and the prognosis of patients with LM.

Conclusion

The factors associated with the occurrence of LM in CRNENs were identified. On the other hand, the relevant prognostic factors for patients with LM-CRNENs were also demonstrated. The nomogram models, based on independent factors, demonstrate greater efficiency and accuracy, promising to provide clinical interventions and decision-making support for patients.

Case study of a neuroendocrine tumor of uncertain origin: single-cell transcriptomics unravels potential primary location

PURPOSE

Determining the primary origin of non-organ-confined neuroendocrine tumors (NETs) for accurate diagnosis and management. Neuroendocrine tumors are rare neoplasms with diverse clinical behaviors. Determining their primary origin remains challenging in cases of non-organ-confined NETs. This study explores the histogenesis of a retroperitoneal, non-functional NET localized between the duodenum and pancreatic head, utilizing advanced molecular diagnostics to elucidate its probable primary source.

METHODS

Initial diagnostic methods, including imaging and histopathology, failed to resolve the tumor's origin. The tumor was subjected to single-cell RNA sequencing (scRNA-seq) and whole exome sequencing (WES). Publicly available transcriptomic datasets from pancreatic and small intestine NETs were used to develop and validate a molecular gene signature for tissue-of-origin identification.

RESULTS

The gene signature distinguished pancreatic and small intestine NETs with high accuracy. The tumor cells presented a molecular profile consistent with a pancreatic origin, likely derived from ectopic pancreatic tissue.

CONCLUSIONS

This case demonstrates the value of integrating scRNA-seq and WES for the molecular characterization of complex NETs. Identifying the tumor's pancreatic origin informed a targeted management approach, avoiding unnecessary systemic treatment and underscoring the potential of single-cell approaches in personalized oncology.

Treatment indicators and prognostic factors in colorectal neuroendocrine neoplasms and adenocarcinoma with neuroendocrine differentiation: a single center retrospective study

PURPOSE

This study compared survival and metastasis occurrence between colorectal neuroendocrine neoplasms (cNEN) and colorectal adenocarcinoma with neuroendocrine differentiation (cNED) and further explored their prognostic factors and treatment indicators.

METHODS

Patients diagnosed as cNEN and cNED in West China Hospital from January 2009 to December 2020 were enrolled. The diagnosis and metastasis rates were calculated. Univariate and multivariate Cox analyses were conducted for progression-free survival (PFS) in cNEN surgical patients, and generalized linear regression was used for metastatic disease.

RESULT

The study enrolled 435 patients, including 257 neuroendocrine tumors (NET), 52 neuroendocrine carcinomas (NEC), 29 mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN), and 97 NED patients, of whom 202 received local resection, and 233 received radical resection. Metastasis rates were higher in MiNEN and NEC groups compared to other groups (NED: 28.9%, MiNEN: 58.6%, NEC: 65.4%, NET: 8.6%, p < 0.001). The liver is the main metastatic site in cNEN, whereas cNED metastasized to various sites. For NEC and MiNEN patients, colon location (p = 0.002) and T stage > 2 (p = 0.040) were associated with disease progression separately. Independent risk factors for metastatic NET included tumor grade G2/G3 (p < 0.001), colon location (p = 0.001), size ≥ 1 cm (p = 0.005), and CK20 partial positive (p < 0.001).

CONCLUSION

cNEN show high metastatic capacity and are challenging to diagnose. More aggressive treatment and follow-up strategies are necessary for those patients. NET tumor grade higher than G2, size larger than 1 cm, or located in the colon should be managed with radical surgery.

Does gamma-glutamyltransferase correlate with liver tumor burden in neuroendocrine tumors?

PURPOSE

In patients with neuroendocrine tumors (NETs) and liver metastases, increased gamma-glutamyltransferase (GGT) is commonly assumed as an indicator for progressive disease. To date, however, empirical data are lacking. This study aimed to investigate associations between GGT and liver tumor burden. In longitudinal analyses, associations of GGT and radiographic responses of liver metastases under therapy were investigated.

METHODS

The cross-sectional sample consisted of 104 patients who were treated at the University Medical Center Hamburg-Eppendorf from 2008 to 2021 (mean age 62.3 ± 12.6 years, 58.7% male). GGT and liver imaging were identified in a time range of 3 months. Radiologic reassessments were performed to estimate liver tumor burden. In a separate longitudinal sample (n = 15), the course of GGT levels under chemotherapy was analyzed. Data were retrospectively analyzed with a univariate ANOVA, linear regression analyses, and Wilcoxon tests.

RESULTS

Of 104 cross-sectionally analyzed patients, 54 (51.9%) showed a GGT elevation. GGT levels and liver tumor burden were positively correlated (p < 0.001), independently from age, gender, primary tumor location, grading, and cholestasis. Notably, GGT increase was associated with a liver tumor burden of >50%. In the longitudinal sample, 10 of 11 patients with progressive disease showed increasing GGT, whereas 4 of 4 patients with regressive disease showed declining GGT.

CONCLUSION

Our findings indicate that GGT is associated with liver tumor burden. Over the course of therapy, GGT appears to change in line with radiographic responses. Further longitudinal studies with larger sample sizes are required to define GGT as a reliable marker for tumor response.

Diagnostic role and prognostic value of tumor markers in high-grade gastro-enteropancreatic neuroendocrine neoplasms

OBJECTIVES

High-grade gastro-enteropancreatic neuroendocrine neoplasms (GEP-NENs) are a heterogeneous group of rare tumors of two different types: well differentiated neuroendocrine tumors grade 3 (NETs G3) and poorly differentiated neuroendocrine carcinomas (NECs). This study aimed to explore the value of eight common preoperative markers in differentiating NETs G3 from NECs and the prognosis prediction of high-grade GEP-NENs.

METHODS

Seventy-two patients diagnosed with high-grade GEP-NENs who underwent surgery at our institution were recruited for this study. Demographic and clinicopathological characteristics, preoperative serum tumor markers, and survival data were collected and analyzed. Kaplan-Meier methods were used to analyze survival rates, and a Cox regression model was used to perform multivariate analyses.

RESULTS

Serum carcinoembryonic antigen (CEA) was dramatically higher in NECs than in NETs G3 (P = 0.025). After follow-up, 57 of the 72 patients remained for survival analysis. Elevated serum carbohydrate antigen 19-9 (CA19-9), CEA, cancer antigen 125 and sialic acid (SA) levels indicated poorer survival of high-grade GEP-NEN patients. Only CA19-9 (HR: 6.901, 95% CI: 1.843 to 25.837, P = 0.004) was regarded as an independent risk factor for overall survival. Serum CA19-9 (HR: 4.689, 95% CI: 1.127 to 19.506, P = 0.034) was also regarded as an independent factor for overall survival in NECs.

CONCLUSIONS

Serum CEA levels can be used to distinguish NETs G3 from NECs. Preoperative CA19-9, CEA, cancer antigen 125 and SA levels have predictive value in the prognosis of high-grade GEP-NENs. Preoperative CA19-9, neuron-specific enolase, and SA levels can predict the prognosis of NECs.

Epidemiological trends and novel prognostic evaluation approaches of patients with stage II-IV colorectal neuroendocrine neoplasms: A population-based study with external validation

OBJECTIVE

This study aimed to clarify the incidence trend of all-stage colorectal neuroendocrine neoplasms (CRNENs), overall survival (OS), and disease-specific survival (DSS) of patients with stage II-IV CRNENs, and to establish relevant nomograms for risk stratification.

METHODS

Among all patients diagnosed with CRNENs in the Surveillance, Epidemiology, and End Results (SEER) database from 1975 to 2019, temporal trends in incidence were assessed. Clinical data of 668 patients with stage II-IV CRNENs from 2010 to 2016 were extracted for survival analysis. Patients were randomly divided into a training cohort and a validation cohort at a ratio of 7:3. Univariate and multivariate cox regression analyses were utilized to identify independent prognostic factors affecting OS outcomes. Competing risk analysis was applied to investigate risk factors related to the DSS of CRNENs. Two nomograms specifically for OS and DSS were developed for patients with stage II-IV CRNENs, their prognostic capabilities were evaluated using calibration curves, receiver operating characteristic (ROC) curves, the time-dependent area under the curve (AUC), and decision-curve analysis (DCA). Our hospital's independent cohort of 62 patients with CRNENs was used as the external validation cohort.

RESULTS

In the period of 1975-2019, the incidence of CRNENs increased steadily with an annual percentage change (APC) of 4.50 (95% confidence interval [CI]: 3.90-5.11, P < 0.05). In total, 668 patients with stage II-IV CRNENs were included in the survival analysis from 2010 and 2016. Independent adverse prognostic factors for both OS and DSS of CRNENs prior treatment included grade III/IV (HR for OS: 4.66, 95%CI: 2.92-7.42; HR for DSS: 4.79, 95%CI: 4.27-5.31), higher TNM stage ([stage III vs stage II] HR for OS: 2.22, 95%CI: 1.25-3.94; HR for DSS: 2.69, 95%CI: 1.96-3.42. [stage IV vs stage II] HR for OS: 3.99, 95%CI: 2.03-7.83; HR for DSS: 4.96, 95%CI: 4.14-5.78), liver metastasis (HR for OS: 1.61, 95%CI: 1.03-2.51; HR for DSS: 1.86, 95%CI: 1.39-2.32), and brain metastasis (HR for OS: 4.57, 95%CI: 1.66-12.58; HR for DSS: 5.01, 95%CI: 4.15-5.87). Advanced age was also identified as a risk factor for OS (HR: 2.03, 95%CI: 1.5-2.76) but not DSS. In terms of treatment, surgery can significantly prolong OS (HR: 0.62, 95%CI: 0.44-0.86) and DSS (HR: 0.67, 95%CI: 0.29-1.05), but chemotherapy and radiation failed to show significance. The respective nomograms for OS and DSS for stage II-IV CRNENs demonstrated high accuracy and robust prediction value in predicting 1-year, 3-year, and 5-year OS and DSS outcomes in training, internal validation, and external validation cohorts. Besides, two online tools regarding OS and DSS prediction were established, facilitating nomogram score calculation, risk group determination, as well as survival prediction for each individual patient.

CONCLUSION

Over the past 40 years, the incidence of CRNENs presented increased steadily, along with improved survival outcomes. Grade III-IV, higher TNM stage, liver metastasis, brain metastasis, and without receiving surgery were found to be associated with worse OS and DSS. Advanced age was a risk factor for OS but not DSS. Nomograms for patients with stage II-IV stage CRNENs are capable of predicting the 1-, 3-, and 5-year OS and DSS rates with high accuracy, and realize risk stratification.

Childhood neuroendocrine tumors of the digestive system: A single center experience

The prevalence and incidence of neuroendocrine tumors (NETs) are increasing in the pediatric population. This increase can be associated with improved diagnostics and increased detection rates of the disease. We aimed to discuss the clinical and pathological characteristics of patients with this rare disease who were followed and treated at our center.The medical records of children (aged 0-18 years) with NETs of the digestive system, followed up and treated between 2007 and 2020 at Ondokuz Mayis University Faculty of Medicine, were reviewed.Overall, 16 patients (8 girls and 8 boys) were analyzed. Fifteen patients had NETs in the appendix; 14 of these had grade I NETs, and 1 had grade II NETs. No additional surgery was performed except for appendectomy. All patients were in complete remission at the last follow-up (median 38 months). The other patient, a 12-year-old girl, had a primary hepatic neuroendocrine carcinoma (grade III NET). Three cycles of neoadjuvant and adjuvant platinum-based chemotherapy were administered, and right hepatectomy was performed to remove the mass. The patient is being followed-up for approximately 3 years without disease recurrence.Most NETs are observed in adults, and most studies have focused on this population. Unlike adults, increasing awareness of the disease in the pediatric population (especially in cases of acute appendicitis), discovering therapeutic treatments, and sharing experiences are crucial for developing an optimal therapeutic approach for pediatric NETs.

Gastroenteropancreatic neuroendocrine neoplasms G3: Novel insights and unmet needs

According to the 2019 WHO pathology grading system, high-grade gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) can be divided into well differentiated neuroendocrine tumors G3 (NETs G3) and poorly differentiated neuroendocrine carcinomas (NECs). GEP-NETs G3 and GEP-NECs present significant differences in driver genes and disease origin. NETs G3 and NECs have been confirmed to be two distinct diseases with different genetic backgrounds, however, this issue remains controversial. The prognosis of NETs G3 is significantly better than that of NECs. The differential diagnosis of GEP-NETs G3 and GEP-NECs should be combined with the patient's medical history, tumor histopathology, Ki-67 index, DAXX/ATRX, TP53 and Rb expression as well as other immunohistochemical indicators. In addition, the treatment strategies of these two subgroups are very different. Here, we summarize recent findings focused on the genomics, clinical manifestations, diagnosis, treatment and other aspects of high-grade GEP-NENs (G3). This review may help further our understanding of the carcinogenesis, diagnosis and treatment of GEP-NENs G3.

Multicenter Analysis of Presacral Neuroendocrine Neoplasms-Clinicopathological Characterization and Treatment Outcomes of a Rare Disease

Background and Aims

Neuroendocrine neoplasms (NENs) of the presacral space are an extremely rare disease entity with largely unknown outcome and no established standard of care treatment. Therefore, we wanted to analyze clinical presentation, histopathological findings, treatment outcomes, and prognosis in a multicentric patient cohort.

Methods

We searched local databases of six German NEN centers for patients with presacral NEN. Retrospective descriptive analyses of age, sex, stage at diagnosis, symptoms, grade, immunohistochemical investigations, biomarkers, treatment, and treatment outcome were performed. Kaplan-Meier analysis was used to determine median overall survival.

Results

We identified 17 patients (11 female, 6 male) with a median age of 50 years (range, 35-66) at diagnosis. Twelve cases presented initially with distant metastases including bone metastases in nine cases. On pathological review the majority of patients had well-differentiated G2 tumors. Immunohistochemical profile resembled rectal NENs. All but one patient had non-functioning tumors. Somatostatin receptor imaging was positive in 14 of 15 investigated cases. Eight patients were treated surgically including palliative resections; 14 patients received somatostatin analogs with limited efficacy. With 14 PRRTs completed, 79% showed clinical benefit, whereas only one patient with neuroendocrine carcinoma (NEC) responded to chemotherapy. Treatment with everolimus in three patients was not successful, whereas cabozantinib resulted in a disease stabilization in a heavily pretreated patient. During a median observation period of 44.5 months, 6 patients died. Median overall survival was not reached.

Conclusion

Presacral NEN are histopathologically similar to rectal NENs. Presacral NEN should be considered as possible primary in NEN of unknown primary. The majority of tumors is non-functioning and somatostatin receptor positive. PRRT demonstrated promising activity; tyrosine kinase inhibitors warrant further investigations. Further molecular characterization and prospective evaluation of this rare tumor entity are needed.

Duodenal neuroendocrine tumor: A rare case report

RATIONALE

Duodenal neuroendocrine tumor (d-NET) is a rare tumor originating in the neuroendocrine system. The clinical manifestations of d-NET are similar to those of other digestive tract tumors, resulting in a lack of specificity and complex clinical symptoms.

PATIENT CONCERNS

A 55-year-old female patient was admitted to our hospital with a chief complaint of an abdominal mass that had been present for more than 4 months.

DIAGNOSES

The upper abdomen enhanced computed tomography scan showed an uneven density mass across the upper abdomen, and the tumor size was approximately 6.2 × 5.8 cm with obvious visible enhancement present in 1 area and a cystic nonenhanced area. The postoperative pathology showed the tumor cells to be positive for chromogranin, synaptophysin, cytokeratin, CD56 (partial weak), negative for vimentin, CD117, DOG-1, CD34, S-100, SMA, desmin, and Ki-67 approximately 2%, which confirmed the diagnosis of d-NETs.

INTERVENTIONS

We preferred laparoscopic surgical exploration, but the tumor started at the ascending part of the duodenum and involved the mesenteric artery. As the branches of the superior mesenteric artery were intertwined with the tumor, it was difficult to operate with the endoscope, so we converted to open laparotomy. The postoperative pathology revealed the presence of d-NET.

OUTCOMES

The patient recovered uneventfully and was discharged after the operation. One-month and 3-month follow-up after surgery, showed no evidence of recurrence.

LESSONS

Radiological imaging studies are insufficient for the differential diagnosis of abdominal mass from other diseases, whereas surgery is the only radical treatment method, and the preferred surgical method is still active radical resection of the tumor.

Chromogranin A Expression in Rectal Neuroendocrine Tumors Is Associated With More Aggressive Clinical Behavior and a Poorer Prognosis

Although rectal neuroendocrine tumors (NETs) with an L-cell phenotype and small size are generally less clinically serious, the new 2019 World Health Organization (WHO) classification system has categorized all of these lesions as malignant. Identifying biomarkers of rectal NETs is thus important for stratifying their clinical behavior. Chromogranin A protein expression was assessed in 538 endoscopically or surgically resected rectal NETs and compared with clinicopathologic factors to identify its clinical and prognostic significance. All of the rectal NETs analyzed (100%) were synaptophysin positive, but chromogranin A labeling was only detected in 111 cases (20.6%). Chromogranin A expression in the rectal NETs was more commonly associated with older age (50 y and older; P=0.013), male sex (P=0.002), radical resection (P=0.003), large tumor size (≥1 cm; P=0.038), muscularis propria invasion (P=0.002), lymphovascular (P=0.014) and perineural (P<0.001) invasion, an involved resection margin (P=0.028), and lymph node metastasis (P=0.003). Patients with chromogranin A expression had higher plasma chromogranin A levels (P=0.023) than those without chromogranin A expression during follow-up. The 10-year disease-free survival rate in rectal NET patients with chromogranin A expression (91.5%) was significantly shorter than the negative cases (99.7%) by both univariate (hazard ratio=14.438; 95% confidence interval: 2.911-71.598; P<0.001) and multivariate (hazard ratio=12.099; 95% confidence interval, 2.044-71.608; P=0.006) analyses. In summary, rectal NETs that are positive for chromogranin A are less common than those with synaptophysin expression and show more aggressive clinical behavior. Chromogranin A is therefore a prognostic indicator of higher recurrence risk in patients with endoscopically or surgically resected rectal NETs.

Large cell neuroendocrine carcinoma in the unusual location of the descending colon

Neuroendocrine neoplasms are most often found in the small intestine, rectum, appendix, and stomach. The colon, excluding the appendix and the cecum, is a rare location for these neoplasms and often gives rise to highly proliferative, poorly differentiated tumors with aggressive features and dismal prognosis. A 32-year-old male presents with a large cell neuroendocrine carcinoma arising from an unusual location, the descending colon. The patient's clinical and imaging characteristics resembles those seen in the much more common neoplasm, colonic adenocarcinoma. Computed tomography and In-111 octreotide scan are limited in diagnosing large cell neuroendocrine carcinoma. Pathologic correlation of a surgical specimen is required to make the correct diagnosis.

Colorectal neuroendocrine tumors: A case series

INTRODUCTION

Neuroendocrine tumors (NET) of the colon and sigmoid colon are uncommon compared to colorectal adenocarcinoma. Few reports have been made of NET of the colon and sigmoid colon that presents with peritonitis and large bowel obstruction.

CASE PRESENTATION

Here, we report two cases of NET of the colon and sigmoid colon, which were diagnosed and treated at our institution. In our first case, a 66-year-old man with a history of abdominal distension was diagnosed with NET via histopathology of the sigmoid colon. The second case involved a 45-year-old woman with the chief complaints of abdominal distention and inability to defecate; specimen histopathology of the descending colon showed neuroendocrine carcinoma features. Clinical outcome was very poor in our patients: eight months after the resection, the second patient demonstrated a sign of metastasis on the liver.

CONCLUSION

An uncommon case of colon and sigmoid colon carcinoma with neuroendocrine and diagnostic difficulties precludes an exact description of the initial diagnostic criteria and management. Thus, our case series offers an overview of initial symptoms, radiological and histopathological features for early diagnosis, and proper management of NET.

The Neuroendocrine Neoplasms of the Digestive Tract: Diagnosis, Treatment and Nutrition

Nuroendocrine neoplasms (NENs) are a group of rare neoplasms originating from dispersed neuroendocrine cells, mainly of the digestive and respiratory tract, showing characteristic histology and immunoprofile contributing to classification of NENs. Some NENs have the ability to produce biogenic amines and peptide hormones, which may be associated with clinical syndromes like, e.g., the carcinoid syndrome caused by unmetabolized overproduced serotonin, hypoglycemic syndrome in case of insulinoma, or Zollinger-Ellison syndrome accompanying gastrinoma. Diagnostics for these include ultrasound with endoscopic ultrasound (EUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron-emission tomography/computed tomography (PET/CT). Different nuclear medicine procedures can also be used, like somatostatin analogues scintigraphy (SRS) and 68Ga-Dota-Peptide PET/CT, as well as biochemical methods to determine the level of general neuroendocrine markers, such as chromogranin A (CgA), 5-hydroxyindolacetic acid (5-HIAA), synaptopfysin and cell type-specific peptide hormones, and neurotransmitters like gastrin, insulin, serotonin, and histamine. NENs influence the whole organism by modulating metabolism. The treatment options for neuroendocrine neoplasms include surgery, somatostatin analogue therapy, radionuclide therapy, chemotherapy, molecular targeted therapies, alpha-interferon therapy, and inhibitors of serotonin production. In the case of hypersensitivity to biogenic amines, a diet that limits the main sources of amines should be used. The symptoms are usually connected with histamine, tyramine and putrescine. Exogenic sources of histamine are products that take a long time to mature and ferment. Patients with a genetic insufficiency of the diamine oxidase enzyme (DAO), and those that take medicine belonging to the group of monoamine oxidases (MAO), are particularly susceptible to the negative effects of amines. Diet plays an important role in the initiation, promotion, and progression of cancers. As a result of the illness, the consumption of some nutrients can be reduced, leading to nutritional deficiencies and resulting in malnutrition. Changes in metabolism may lead to cachexia in some patients suffering from NENs. The aim of this narrative review was to advance the knowledge in this area, and to determine possibilities related to dietary support. The authors also paid attention to role of biogenic amines in the treatment of patients with NENs. We can use this information to better understand nutritional issues faced by patients with gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs), and to help inform the development of screening tools and clinical practice guidelines.

Evaluation in humans of ELF-EMF exposure on chromogranin A, a marker of neuroendocrine tumors and stress

Chromogranin A (CgA), which is a major protein in adrenal chromaffin cells and adrenergic neurons, is a clinically relevant endocrine and neuroendocrine tumor marker including pheochromocytomas, neuroblastomas, and related neurogenic tumors. In this study, we looked at the effect in humans of chronic daily exposure to a 50-Hz magnetic field. We examined in 15 men (38.0 ± 0.9 years) the effects of chronic daily exposure to a 50-Hz magnetic field for 1-20 yrs both at home and at work. EMDEX II dosimeters were used to record magnetic field all day long every 30 s. for 1 week. The weekly geometric mean of the individual exposures ranged from 0.1 to 2.6 μT. Blood samples were taken hourly between 20:00 h and 08:00 h. CgA patterns of exposed subjects were compared to age-matched controls. The results of exposed subjects were compared with those for 15 unexposed men who served as controls and whose individual exposure was ten times lower ranging from 0.004 to 0.092 μT. This work shows that in the control group the serum CgA levels exhibited a nighttime peak with a progressive decline of the serum concentrations and a nadir in the morning. Both the profile and the serum concentrations of CgA, a marker of neuroendocrine tumors and stress, did not appear to be impaired in the subjects chronically exposed over a long period (up to 20 yrs) to magnetic fields though a trend toward lower levels were found at the highest exposure (>0.3 μT). This does not rule out, however, that the potential deleterious risk of ELF-EMF on frail populations such as children and the elderly may be greater at low exposure and should hence be documented, at least for their residential exposure.

Management of Gastrointestinal Neuroendocrine Tumors

Neuroendocrine neoplasms (NENs) are derived from neuroendocrine cell system and can have benign or malignant characteristics. They are rare tumors, but have been increasing in incidence over the past 40 years. Patients with NENs may develop symptoms due to primary tumor invasion, metastasis, or from secretion of hormonally active tumor substances. Multiple imaging modalities are used for diagnosis and staging, including specialty scans such as ¹¹¹In pentetreotide (Octreoscan) and ⁶⁸Gallium-DOTATATE, along with endoscopy, endoscopic ultrasound, and biochemical marker testing. Treatment involves both surgical approach, for both primary and metastatic lesions, as well as medical management for symptom management and disease progression. This article will review the current clinical knowledge regarding the diagnosis, treatment, and prognosis of these fascinating neoplasms and the associated hormonal syndromes.

Poorly differentiated neuroendocrine rectal carcinoma with uncommon immune-histochemical features and clinical presentation with a subcutaneous metastasis, treated with first line intensive triplet chemotherapy plus bevacizumab FIr-B/FOx regimen: an experience of multidisciplinary management in clinical practice

Background

Neuroendocrine tumors (NETs) are heterogeneous, widely distributed tumors arising from neuroendocrine cells. Gastrointestinal (GI)-NETs are the most common and NETs of the rectum represent 15, 2% of gastrointestinal malignancies. Poorly differentiated neuroendocrine carcinomas of the GI tract are uncommon. We report a rare case of poorly differentiated locally advanced rectal neuroendocrine carcinoma with nodal and a subcutaneous metastasis, with a cytoplasmic staining positive for Synaptophysin and Thyroid Transcription Factor-1.

Case presentation

A 72-year-old male presented to hospital, due to lumbar, abdominal, perineal pain, and severe constipation. A whole-body computed tomography scan showed a mass of the right lateral wall of the rectum, determining significant reduction of lumen caliber. It also showed a subcutaneous metastasis of the posterior abdominal wall. Patient underwent a multidisciplinary evaluation, diagnostic and therapeutic plan was shared and defined. The pathological examination of rectal biopsy and subcutaneous nodule revealed features consistent with small-cell poorly differentiated neuroendocrine carcinoma. First line medical treatment with triplet chemotherapy and bevacizumab, according to FIr-B/FOx intensive regimen, administered for the first time in this young elderly patient affected by metastatic rectal NEC was highly active and tolerable, as previously reported in metastatic colo-rectal carcinoma (MCRC). A consistent rapid improvement in clinical conditions were observed during treatment. After 6 cycles of treatment, CT scan and endoscopic evaluation showed clinical complete response of rectal mass and lymph nodes; patient underwent curative surgery confirming the pathologic complete response at PFS 9 months.

Discussion and conclusions

This case report of a locally advanced rectal NEC with an unusual subcutaneous metastasis deserves further investigation of triplet chemotherapy-based intensive regimens in metastatic GEP NEC.

Analysis of 72 patients with colorectal high-grade neuroendocrine neoplasms from three Chinese hospitals

BACKGROUND

Colorectal high-grade neuroendocrine neoplasms (HGNENs) are rare and constitute less than 1% of all colorectal malignancies. Based on their morphological differentiation and proliferation identity, these neoplasms present heterogeneous clinicopathologic features. Opinions regarding treatment strategies for and improvement of the clinical outcomes of these patients remain controversial.

AIM

To delineate the clinicopathologic features of and explore the prognostic factors for this rare malignancy.

METHODS

This observational study reviewed the data of 72 consecutive patients with colorectal HGNENs from three Chinese hospitals between 2000 and 2019. The clinicopathologic characteristics and follow-up data were carefully collected from their medical records, outpatient reexaminations, and telephone interviews. A survival analysis was conducted to evaluate their outcomes and to identify the prognostic factors for this disease.

RESULTS

According to the latest recommendations for the classification and nomenclature of colorectal HGNENs, 61 (84.7%) patients in our cohort had poorly differentiated neoplasms, which were categorized as high-grade neuroendocrine carcinomas (HGNECs), and the remaining 11 (15.3%) patients had well differentiated neoplasms, which were categorized as high-grade neuroendocrine tumors (HGNETs). Most of the neoplasms (63.9%) were located at the rectum. More than half of the patients (51.4%) presented with distant metastasis at the date of diagnosis. All patients were followed for a median duration of 15.5 mo. In the entire cohort, the median survival time was 31 mo, and the 3-year and 5-year survival rates were 44.3% and 36.3%, respectively. Both the univariate and multivariate analyses demonstrated that increasing age, HGNEC type, and distant metastasis were risk factors for poor clinical outcomes.

CONCLUSION

Colorectal HGNENs are rare and aggressive malignancies with poor clinical outcomes. However, patients with younger age, good morphological differentiation, and without metastatic disease can have a relatively favorable prognosis.

Endoscopic features and associated histology of an basaloid squamous cell carcinoma of the esophagus at the very early stage

Background

Basaloid squamous cell carcinoma of the esophagus (BSCCE) is generally detected at advanced stage and the prognosis is poorer than advanced conventional esophageal squamous cell carcinoma. Therefore, early detection is a critical to improve patients’ survival. However, only a few cases of early BSCCE have been reported and the endoscopic features of early BSCCE are not well described. We herein report the endoscopic features and associated histology of an early BSCCE limited within the mucosal lamina propria (m2). To our knowledge, this is the earliest BSCCE reported to date.

Case presentation

A 62-year-old male patient was admitted to our hospital because of epigastric pain for 3 months. White light endoscopy revealed a flat lesion with mild sloping at the periphery. The lesion was covered with leukoplakia, and normal vascular network could not be seen in the lesion. Magnifying endoscopy with narrow-band imaging showed abnormal intra-papillary capillary loop categorized as type B1 according to the classification of the Japan Esophageal Society. Iodine staining revealed a less-stained lesion. The lesion was completely resected through endoscopic submucosal dissection. Histopathologically, tumor cells, which were limited within the mucosal lamina propria, formed solid nests and lobule structures, with ribbon-like arrangement of sparse cytoplasm and round to ovoid hyperchromatic nuclei. A final diagnosis of early BSCCE was established.

Conclusions

This is the earliest BSCCE reported to date. The prominent lesion with a gentle rising slope and less-staining or abnormal stain might be initial feature of early BSCCE.

Chromogranin A: From Laboratory to Clinical Aspects of Patients with Neuroendocrine Tumors

Background. Neuroendocrine tumors (NETs) are characterized by having behavior and prognosis that depend upon tumor histology, primary site, staging, and proliferative index. The symptoms associated with carcinoid syndrome and vasoactive intestinal peptide tumors are treated with octreotide acetate. The PROMID trial assesses the effect of octreotide LAR on the tumor growth in patients with well-differentiated metastatic midgut NETs. The CLARINET trial evaluates the effects of lanreotide in patients with nonfunctional, well-, or moderately differentiated metastatic enteropancreatic NETs. Everolimus has been approved for the treatment of advanced pancreatic NETs (pNETs) based on positive PFS effects, obtained in the treated group. Sunitinib is approved for the treatment of patients with progressive gastrointestinal stromal tumor or intolerance to imatinib, because a randomized study demonstrated that it improves PFS and overall survival in patients with advanced well-differentiated pNETs. In a phase II trial, pasireotide shows efficacy and tolerability in the treatment of patients with advanced NETs, whose symptoms of carcinoid syndrome were resistant to octreotide LAR. An open-label, phase II trial assesses the clinical activity of long-acting repeatable pasireotide in treatment-naive patients with metastatic grade 1 or 2 NETs. Even if the growth of the neoplasm was significantly inhibited, it is still unclear whether its antiproliferative action is greater than that of octreotide and lanreotide. Because new therapeutic options are needed to counter the natural behavior of neuroendocrine tumors, it would also be useful to have a biochemical marker that can be addressed better in the management of these patients. Chromogranin A is currently the most useful biomarker to establish diagnosis and has some utility in predicting disease recurrence, outcome, and efficacy of therapy.

Colorectal cancer: genetic abnormalities, tumor progression, tumor heterogeneity, clonal evolution and tumor-initiating cells

Colon cancer is the third most common cancer worldwide. Most colorectal cancer occurrences are sporadic, not related to genetic predisposition or family history; however, 20-30% of patients with colorectal cancer have a family history of colorectal cancer and 5% of these tumors arise in the setting of a Mendelian inheritance syndrome. In many patients, the development of a colorectal cancer is preceded by a benign neoplastic lesion: either an adenomatous polyp or a serrated polyp. Studies carried out in the last years have characterized the main molecular alterations occurring in colorectal cancers, showing that the tumor of each patient displays from two to eight driver mutations. The ensemble of molecular studies, including gene expression studies, has led to two proposed classifications of colorectal cancers, with the identification of four/five non-overlapping groups. The homeostasis of the rapidly renewing intestinal epithelium is ensured by few stem cells present at the level of the base of intestinal crypts. Various experimental evidence suggests that colorectal cancers may derive from the malignant transformation of intestinal stem cells or of intestinal cells that acquire stem cell properties following malignant transformation. Colon cancer stem cells seem to be involved in tumor chemoresistance, radioresistance and relapse.