Gastrointestinal carcinoids: the evolution of diagnostic strategies

Chromogranin A as a diagnostic marker of pheochromocytoma and paraganglioma: A systematic review and meta-analysis

OBJECTIVES

This work aims to assess the diagnostic value of chromogranin A (CgA) in the laboratory diagnosis of neuroendocrine tumors classified as pheochromocytoma and paraganglioma (PPGL).

METHODS

A comprehensive search was performed in PubMed, Embase, the Cochrane Library, and Web of Science databases to obtain relevant studies reporting the diagnostic accuracy of CgA in patients with PPGL. The search involved studies written in English between the time of library inception and May 1, 2023. We computed the pooled sensitivity, specificity, and diagnostic odds ratio (DOR). Additionally, the receiver operating characteristic curve and area under the curve (AUC) were determined. The heterogeneity was assessed using the Chi-square test and the I2 test. The subgroup analyses were performed to investigate the origins of heterogeneity. Stata 15.1 statistical software was used in all data analyses.

RESULTS

This meta-analysis included 13 studies involving 1470 patients. CgA had a pooled diagnostic sensitivity of 0.86 (95% CI 0.81-0.91), a specificity of 0.90 (95% CI 0.81-0.95), and a DOR of 57 (95% CI 23-142). CgA had an AUC of 0.93. The studies did not reveal any threshold effect (r = -0.165; p > 0.05). The subgroup analyses revealed that the control group category and the detection method caused the overall heterogeneity.

CONCLUSIONS

Our study suggests that CgA is a helpful PPGL biomarker. However, relying solely on CgA for diagnosis is not advisable. A comprehensive approach is essential for accurate diagnosis. Future large-scale research is needed to refine CgA's clinical application.

Gastric Neuroendocrine Tumors According to the 2019 World Health Organization Grading System: A Single-Center, Retrospective Study

Background/Aims

Although gastric neuroendocrine tumors (NETs) are uncommon neoplasms, their prevalence is increasing. The clinical importance of the World Health Organization (WHO) classification of gastric NETs, compared with NETs in other organs, has been underestimated. This study aimed to systematically evaluate the clinical and pathologic characteristics of gastric NETs based on the 2019 WHO classification and to assess the survival outcomes of patients from a single-center with a long-term follow-up.

Methods

The medical records of 427 patients with gastric NETs who underwent endoscopic or surgical resection between January 2000 and March 2020 were retrospectively reviewed. All specimens were reclassified according to the 2019 WHO classification. The clinicopathologic characteristics, treatment, and oncologic outcomes of 139 gastric NETs were analyzed.

Results

The patients' median age was 53.0 years (interquartile range [IQR], 46.0 to 63.0 years). The median follow-up period was 36.0 months (IQR, 15.0 to 63.0 months). Of the patients, 92, 44, and 3 had grades 1, 2, and 3 NETs, respectively. The mean tumor size significantly increased as the tumor grade increased (p=0.025). Patients with grades 2 and 3 gastric NETs more frequently had lymphovascular invasion (29.8% vs 10.9%, p=0.005) and deeper tissue invasion (8.5% vs 0%, p=0.012) than those with grade 1 tumors. The overall disease-specific survival rate was 100%. Two patients with grades 2-3 gastric NETs experienced extragastric recurrence.

Conclusions

Although gastric NETs have an excellent prognosis, grade 2 or grade 3 gastric NETs are associated with a larger size, deeper invasion, and extragastric recurrence, which require active treatment.

Systemic Therapy for Tumor Control in Metastatic Well-Differentiated Gastroenteropancreatic Neuroendocrine Tumors: ASCO Guideline

PURPOSE

To develop recommendations for systemic therapy for well-differentiated grade 1 (G1) to grade 3 (G3) metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs).

METHODS

ASCO convened an Expert Panel to conduct a systematic review of relevant studies and develop recommendations for clinical practice.

RESULTS

Eight randomized controlled trials met the inclusion criteria for the systematic review.

RECOMMENDATIONS

Somatostatin analogs (SSAs) are recommended as first-line systemic therapy for most patients with G1-grade 2 (G2) metastatic well-differentiated GI-NETs. Observation is an option for patients with low-volume or slow-growing disease without symptoms. After progression on SSAs, peptide receptor radionuclide therapy (PRRT) is recommended as systematic therapy for patients with somatostatin receptor (SSTR)-positive tumors. Everolimus is an alternative second-line therapy, particularly in nonfunctioning NETs and patients with SSTR-negative tumors. SSAs are standard first-line therapy for SSTR-positive pancreatic (pan)NETs. Rarely, observation may be appropriate for asymptomatic patients until progression. Second-line systemic options for panNETs include PRRT (for SSTR-positive tumors), cytotoxic chemotherapy, everolimus, or sunitinib. For SSTR-negative tumors, first-line therapy options are chemotherapy, everolimus, or sunitinib. There are insufficient data to recommend particular sequencing of therapies. Patients with G1-G2 high-volume disease, relatively high Ki-67 index, and/or symptoms related to tumor growth may benefit from early cytotoxic chemotherapy. For G3 GEP-NETs, systemic options for G1-G2 may be considered, although cytotoxic chemotherapy is likely the most effective option for patients with tumor-related symptoms, and SSAs are relatively ineffective. Qualifying statements are provided to assist with treatment choice. Multidisciplinary team management is recommended, along with shared decision making with patients, incorporating their values and preferences, potential benefits and harms, and other characteristics and circumstances, such as comorbidities, performance status, geographic location, and access to care.Additional information is available at www.asco.org/gastrointestinal-cancer-guidelines.

Primary neuroendocrine tumor in the retroperitoneal cavity: A rare case report

INTRODUCTION AND IMPORTANCE

Neuroendocrine tumors (NETs) are rare malignancies, accounting for a small percentage of gastrointestinal and bronchopulmonary cancers. Retroperitoneal NETs are infrequent and can be primary or metastatic. They are commonly metastatic rather than primary tumors, with primary retroperitoneal NETs being exceptionally rare.

CASE PRESENTATION

A 38-year-old woman presented with left flank pain persisting for one year, which had progressively worsened. Imaging revealed a large retroperitoneal mass exerting pressure on the stomach, spleen, liver, and upper pole of the left kidney. A biopsy of the tumor was done and the results were consistent with NET. The tumor, which measured approximately 19 × 12.5 × 11 cm, was surgically removed, and the pathological findings were consistent with the results of the biopsy prior to the surgery.

CLINICAL DISCUSSION

Neuroendocrine tumors are rare and exhibit diverse characteristics based on location, size, hormone secretion, and metastasis. Retroperitoneal neuroendocrine tumors are typically metastatic and rarely primary. The extremely large size of the tumor in this case highlights the surgical challenges associated with retroperitoneal NETs. Imaging, such as CT and MRI, plays a crucial role in diagnosis.

CONCLUSION

The study emphasizes the need to consider primary NETs as a possible cause of large retroperitoneal masses, especially if the tumor size is significant. Surgical resection is the primary treatment option with generally favorable outcomes. However, the size of the tumor can complicate treatment, and further research is needed to evaluate the effectiveness of postoperative adjuvant therapy and develop therapeutic approaches for recurrent NETs.

Gastrik polipler: 10 yıllık endoskopik işlemin retrospektif analizi

Objective: Gastric polyps are gastric mucosal protrusions that are usually asymptomatic and detected incidentally during upper gastrointestinal system endoscopy. In this study, the incidence, location and general characteristics of gastric polyps were evaluated. Materials and methods: Upper gastrointestinal system endoscopies performed in a tertiary hospital for a period of ten years were evaluated retrospectively. Demographic characteristics of the patients, gastroscopy indications, morphological and histological characteristics of polyps were recorded. Results: Gastric polyps were found in 347 (1.4%) of a total of 25230 gastroscopy patients. The mean age of the patients was 61.04 ± 15.05 and 64.3% were female. 124 (35.7%) of the patients were male and 223 (64.3%) were female. The most common endoscopic indication (74.1%) of the patients with polyps was dyspepsia. Most of the polyps (55.3%) were smaller than 5 mm and the most common site was the antrum. Hyperplastic polyp (44.4%) was detected the most. 42.9% of the patients with polyps were positive for Helicobacter pylori. In addition, 58% of adenomatous polyps were accompanied by dysplasia. Conclusion: Hyperplastic polyps were the most common polyp type in our population. Full excision of polyps over 5 mm (especially adenomatous polyps) is recommended instead of biopsy, as they may contain dysplasia foci. In addition, it was thought that taking polyps smaller than 5 mm into endoscopic follow-up without excision was more cost-effective.

Primary hepatic neuroendocrine neoplasm diagnosed by somatostatin receptor scintigraphy: A case report

BACKGROUND

Primary hepatic neuroendocrine neoplasm (NEN) is a rare condition, and it is difficult to differentiate between primary and metastatic hepatic NENs. Herein, we report a case of primary hepatic NEN that initially mimicked a hemangioma but showed a gradual increase in size on long-term careful observation.

CASE SUMMARY

A 47-year-old woman was incidentally diagnosed with a 12-mm liver mass, suspected to be a hemangioma. Since then, regular follow-up had been carried out. Ten years later, she was referred to our institute due to the tumor (located in segment 4) having increased to 20 mm. Several imaging studies depicted no apparent extrahepatic lesion. Positron emission tomography (PET)/computed tomography exhibited significant accumulation in the mass lesion, which made us consider the possibility of malignancy. Left hepatectomy was performed. The histopathological diagnosis was neuroendocrine tumor grade 2, with somatostatin receptor 2a/5 positivity. Postoperative somatostatin receptor scintigraphy (SRS) showed no other site, leading to the diagnosis of NEN of primary hepatic origin. The gradual growth of the hepatic NEN over 10 years suggested that it was likely to be a primary liver tumor.

CONCLUSION

In this case, positivity on PET and postoperative SRS may have helped determine whether the tumor was primary or metastatic.

Emerging Therapeutic Concepts and Latest Diagnostic Advancements Regarding Neuroendocrine Tumors of the Gynecologic Tract

Neuroendocrine neoplasms (NENs) are particularly rare in all sites of the gynecological tract and include a variety of neoplasms with variable prognosis, dependent on histologic subtype and site of origin. Following the expert consensus proposal of the International Agency for Research on Cancer (IARC), the approach in the latest World Health Organization (WHO) Classification System of the Female Genital Tumours is to use the same terminology for NENs at all body sites. The main concept of this novel classification framework is to align it to all other body sites and make a clear distinction between well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). The previous WHO Classification System of the Female Genital Tumours featured more or less the same principle, but used the terms ‘low-grade neuroendocrine tumor’ and ‘high-grade neuroendocrine carcinoma’. Regardless of the terminology used, each of these two main categories include two distinct morphological subtypes: NETs are represented by typical and atypical carcinoid and NEC are represented by small cell neuroendocrine carcinoma (SCNEC) and large cell neuroendocrine carcinoma (LCNEC). High-grade NECs, especially small cell neuroendocrine carcinoma tends to be more frequent in the uterine cervix, followed by the endometrium, while low-grade NETs usually occur in the ovary. NENs of the vulva, vagina and fallopian tube are exceptionally rare, with scattered case reports in the scientific literature.

Surgical palliation in poorly differentiated neuroendocrine carcinoma of the hypopharynx: Case report

Background

Primary neuroendocrine carcinomas (NECs) are very rare entities accounting for 0.49% of all malignancies. Within the head and neck, the most common sites are the larynx and paranasal sinuses, while the hypopharynx is seldom described.

Case

We present a patient with a poorly differentiated metastatic NEC of the hypopharynx treated palliatively with organ‐preserving surgery and post‐operative chemotherapy, and literature review for well‐documented pure hypopharyngeal NECs. Our patient died of chest infection during chemotherapy, 4 months after surgery.

Conclusion

Chemotherapy remains the mainstay of treatment in the presence of metastases with 2‐year overall survival of 15.7%. Due to the aggressive nature of poorly differentiated metastatic NECs, surgical management is seldom considered. We report and advocate the successful palliative role of organ‐preserving, minimally invasive trans‐oral LASER micro‐surgery and neck dissection to control loco‐regional head and neck disease, safe‐guarding better quality of home life, despite limited life expectancy for this condition.

Label-free identification of early gastrointestinal neuroendocrine tumors via biomedical multiphoton microscopy and automatic image analysis

At present, early diagnosis and treatment is the most effective way to treat early gastrointestinal neuroendocrine tumors. Therefore, we attempted to carry out multiphoton imaging of early neuroendocrine tumors because of its ability to label-free image tissue microstructure at the cellular level. Imaging results show that this imaging technique can quickly identify the histopathological changes in mucosa and submucosa caused by tumor invasion. Furthermore, we performed automatic image analysis on SHG images and extracted two optical diagnostic features-collagen density and average intensity, and also found obvious differences in the density as well as average intensity of collagen fibers in tumor microenvironment using a series of quantitative analysis. These findings may further facilitate the development of multiphoton microscopic imaging technique for clinical use.

Neuroendocrine Neoplasms of the Small Bowel and Pancreas

The traditionally promulgated perspectives of neuroendocrine neoplasms (NEN) as rare, indolent tumours are blunt and have been outdated for the last 2 decades. Clear increments in their incidence over the past decades render them increasingly clinically relevant, and at initial diagnosis many present with nodal and/or distant metastases (notably hepatic). The molecular pathogenesis of these tumours is increasingly yet incompletely understood. Those arising from the small bowel (SB) or pancreas typically occur sporadically; the latter may occur within the context of hereditary tumour predisposition syndromes. NENs can also be associated with endocrinopathy of hormonal hypersecretion. Tangible advances in the development of novel biomarkers, functional imaging modalities and therapy are especially applicable to this sub-set of tumours. The management of SB and pancreatic neuroendocrine tumours (NET) may be challenging, and often comprises a multidisciplinary approach wherein surgical, medical, interventional radiological and radiotherapeutic modalities are implemented. This review provides a comprehensive overview of the epidemiology, pathophysiology, diagnosis and treatment of SB and pancreatic NETs. Moreover, we provide an outlook of the future in these tumour types which will include the development of precision oncology frameworks for individualised therapy, multi-analyte predictive biomarkers, artificial intelligence-derived clinical decision support tools and elucidation of the role of the microbiome in NEN development and clinical behaviour.

Role of biomarker tests for diagnosis of neuroendocrine tumours

Neuroendocrine tumours (NETs) are neoplasms that arise from neuroendocrine cells. Neuroendocrine cells and their tumours can secrete a wide range of amines and polypeptide hormones into the systemic circulation. This feature has triggered widespread investigation into circulating biomarkers for the diagnosis of NETs as well as for the prediction of the biological behaviour of tumour cells. Classic examples of circulating biomarkers for gastroenteropancreatic NETs include chromogranin A, neuron-specific enolase and pancreatic polypeptide as well as hormones that elicit clinical syndromes, such as serotonin and its metabolites, insulin, glucagon and gastrin. Biomarker metrics of general markers for diagnosing all gastroenteropancreatic NET subtypes are limited, but specific hormonal measurements can be of diagnostic value in select cases. In the past decade, methods for detecting circulating transcripts and tumour cells have been developed to improve the diagnosis of patients with NETs. Concurrently, modern scanning techniques and superior radiotracers for functional imaging have markedly expanded the options for clinicians dealing with NETs. Here, we review the latest research on biomarkers in the NET field to provide clinicians with a comprehensive overview of relevant diagnostic biomarkers that can be implemented in dedicated situations.

Clinical, pathological, and demographic factors associated with development of recurrences after surgical resection in elderly patients with neuroendocrine tumors

Background

Incidence of locoregional neuroendocrine tumors (NETs) is rising. However, after curative resection, the patterns and risk factors associated with recurrence remain unknown. Consensus guidelines recommend surveillance every 6-12 months for up to 10 years after surgery for resected, well-differentiated NETs irrespective of patient demographics, site, grade or stage of tumor with few exceptions.

Patients and methods

From the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified localized and regional stage NET patients who underwent surgical resection between January 2002 and December 2011. Development of recurrence was identified by capturing at least two claims indicative of metastatic disease until 31 December 2013.

Results

Of the 2366 identified patients (median age 73 years), 369 (16%) developed metastatic disease within 5 years and only an additional 1% developed metastases between years 5 and 10 with the majority dying due to unrelated causes. The 5-year risk of developing metastases (hazard ratio, HR) varied significantly (log-rank P < 0.001) by grade: 9.9% versus 25.9% (2.2) versus 48.1% (4.4) for grades 1, 2, and  ≥ 3, respectively; stage: 10.3% versus 31.1% (2.8) for localized versus regional; primary tumor size: 7.6% versus 15% (1.3) versus 26.6% (1.5) for <1, 1-2, and > 2 cm, respectively; and site: ranging from 11.3% for colon to 23.9% for pancreas.

Conclusions

Contrary to current guidelines, our study suggests that surveillance recommendations should be tailored according to patient and tumor characteristics. Surveillance past 5 years may be avoided in elderly patients with competing morbidities or low risk of recurrence. Pancreatic, lung, higher grade, and regional NETs have a higher risk of recurrence and may be considered for future adjuvant trials.

Clinicopathological hallmarks and biomarkers of colorectal neuroendocrine neoplasms

Chromogranin A (CgA) is a well-established marker for diagnosis and follow up of patients with gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN). Recently, it has been shown that plasma levels of CgA correlate with tumor load and predict survival of patients with NEN of the small bowel. It is assumed that this is as well valid for NEN of the colon and rectum, however, this is not supported by data. To evaluate this assumption, we analyzed 62 patients with NEN of the colon and rectum listed in the Marburg GEP-NEN registry for clinicopathological characteristics, expression and plasma levels of CgA. The present study demonstrates that immunohistochemical CgA and synaptophysin are good markers for histological diagnosis in patients with NEN of the colon and rectum. However, plasma CgA is a poor marker to follow-up these patients because only a minority exhibited increased levels which did not increase significantly during tumor progression. In contrast to NEN of the small bowel, there is no correlation of CgA plasma levels with tumor burden or survival. Patients with NEN of the colon and rectum displayed a relatively good prognosis resulting in a median survival of 8.5 years. However, a subset of patients affected by G3 neoplasms, exhibited a poorer prognosis with a median survival of 2.5 years. Taken together, CgA is a valuable marker for immunohistochemical diagnosis, but CgA plasma concentration is not suitable to mirror tumor burden or prognosis in patients with NEN of the colon and rectum.

Fluorine-18 labeled amino acids for tumor PET/CT imaging

Tumor glucose metabolism and amino acid metabolism are usually enhanced, ¹⁸F-FDG for tumor glucose metabolism PET imaging has been clinically well known, but tumor amino acid metabolism PET imaging is not clinically familiar. Radiolabeled amino acids (AAs) are an important class of PET/CT tracers that target the upregulated amino acid transporters to show elevated amino acid metabolism in tumor cells. Radiolabeled amino acids were observed to have high uptake in tumor cells but low in normal tissues and inflammatory tissues. The radionuclides used in labeling amino acids include ¹⁵O, ¹³N, ¹¹C, ¹²³I, ¹⁸F and ⁶⁸Ga, among which the most commonly used is ¹⁸F [1]. Available data support the use of certain ¹⁸F-labeled AAs for PET/CT imaging of gliomas, neuroendocrine tumors, prostate cancer and breast cancer [2, 3]. With the progress of the method of ¹⁸F labeling AAs [4-6], ¹⁸F-labeled AAs are well established for tumor PET/CT imaging. This review focuses on the current status of key clinical applications of 18F-labeled AAs in tumor PET/CT imaging.

Evaluation and management of gastric epithelial polyps

Gastric polyps include a wide spectrum of lesions with different histology and neoplastic potential. They are found in up to 6% of upper gastrointestinal endoscopy and are usually asymptomatic and incidentally diagnosed, being in the vast majority epithelial gastric polyps. Hyperplastic, fundic gland and adenomas are the most common types of gastric polyps and, although each type may have typical endoscopic appearances, they all must be sampled at the initial endoscopy for histological assessment. Also, the normal appearing gastric mucosa should be sampled to stage atrophic changes, rule out endoscopically non-visible dysplasia and to diagnose Helicobacter pylori. Polyposis syndromes that affect the stomach are rare but should be taken into account. Hamartomatous polyps can be found in Juvenile polyposis, Cowden syndrome and Peutz-Jeghers syndrome. On the other hand, multiple fundic gland polyps are present in the majority of patients with familial adenomatous polyposis. In this study we provide a comprehensive review on the evaluation and management of gastric epithelial polyps, in this way helping physicians to properly handle this type of lesions.

Clinicopathological Features and Prognostic Factors of Colorectal Neuroendocrine Neoplasms

Background. Limited research is available regarding colorectal NENs and the prognostic factors remain controversial. Materials and Methods. A total of 68 patients with colorectal NENs were studied retrospectively. Clinical characteristics and prognosis between colonic and rectal NENs were compared. The Cox regression models were used to evaluate the predictive capacity. Results. Of the 68 colorectal NENs patients, 43 (63.2%) had rectal NENs, and 25 (36.8%) had colonic NENs. Compared with rectal NENs, colonic NENs more frequently exhibited larger tumor size (P < 0.0001) and distant metastasis (P < 0.0001). Colonic NENs had a worse prognosis (P = 0.027), with 5-year overall survival rates of 66.7% versus 88.1%. NET, NEC, and MANEC were noted in 61.8%, 23.5%, and 14.7% of patients, respectively. Multivariate analyses revealed that tumor location was not an independent prognostic factor (P = 0.081), but tumor size (P = 0.037) and pathological classification (P = 0.012) were independent prognostic factors. Conclusion. Significant differences exist between colonic and rectal NENs. Multivariate analysis indicated that tumor size and pathological classification were associated with prognosis. Tumor location was not an independent factor. The worse outcome of colonic NENs observed in clinical practice might be due not only to the biological differences, but also to larger tumor size in colonic NENs caused by the delayed diagnosis.

Neuroendrocrine tumors of the uterine cervix: A therapeutic challenge for gynecologic oncologists

Neuroendocrine tumors (NETs) are aggressive diseases developing from neuroendocrine cells that most frequently involve the gastro-entero-pancreatic tract and the lung, but more rarely are found in almost all body tissues. Limited biological and clinical data are currently available for NETs in uncommon sites, such as female genital tract. NETs represent 0.9% to 1.5% of the tumors of the uterine cervix. They are more likely to have lymph-vascular space invasion and lymph node involvement, and to develop local and distant relapses when compared with the mostly common cervical squamous cell carcinomas or adenocarcinomas. Positive immunostaining for synaptophysin, chromogranin, CD56, and neuron-specific enolase is often detected in cervical NETs . The most recent editions of the World Health Organization Classification of Gynecologic Tract tumors grouped cervical carcinoid tumor and atypical carcinoid tumor into low-grade NETs and cervical small cell neuroendocrine carcinoma and large cell neuroendocrine carcinoma into high-grade NETs. High-risk HPV DNA is detected in almost all cervical high-grade NETs. No treatment guidelines, based on prospective, well-designed clinical trials, are currently available due to the rarity of these tumors. Many authors have reported different multimodality approaches, mainly derived from NETs of the lung. These usually consist in radical hysterectomy followed by adjuvant chemotherapy or concurrent chemoradiation for early stage disease, definitive concurrent chemoradiation sometimes preceded by neoadjuvant chemotherapy and followed by adjuvant chemotherapy for locally advanced disease, and palliative chemotherapy for metastatic disease. In this systematic review, we address the histologic classification of cervical NETs, analyze their pathogenesis and overall prognosis, and evaluate the different treatment modalities described in the literature, in order to offer a possible algorithm that may help the clinicians in diagnosing and treating patients with these uncommon and aggressive malignancies.

Nonlinear optical microscopy for label-free detection of gastrointestinal neuroendocrine tumors

Neuroendocrine tumors (NETs), which are rare and slow-growing neoplasms, pose a diagnostic challenge as they are clinically silent at the time of presentation. Here, gastrointestinal neuroendocrine tumors were researched by nonlinear microscopy, and results demonstrate that this technique has the capability to identify neuroendocrine tumors in the absence of labels and can, in particular, detect rare neuroendocrine tumor cells, vascular invasion, desmoplastic reaction, and fibroelastosis induced by neuroendocrine tumors. These conclusions highlight the possibility of nonlinear optical microscopy as a diagnostic tool for label-freely differentiating neuroendocrine tumors by these histopathologic features.

Epidemiological features of gastroenteropancreatic neuroendocrine tumors in Chengdu city with a population of 14 million based on data from a single institution

AIM

Recent studies on gastroenteropancreatic neuroendocrine tumors (GEP-NETs) in the United States as well as the European studies demonstrate an increasing GEP-NETs incidence. Most information on the epidemiology of neuroendocrine tumors comes from western countries. However, the epidemiological profile of GEP-NETs in West China is still unclear. The aim of study was to reflect the regional features of GEP-NETs in Chengdu city of West China based on data from a single institution.

METHODS

West China Hospital (WCH), the largest university hospital located in Chengdu (West China) with population of 14.04 million, has established a serial of databases in recent years. According to the data from Medical Records Section of WCH and Chengdu Health Bureau, the total patients per year in WCH covered about 25.6-28% patients of Chengdu city during the 5 years. Therefore, we have used GEP-NETs diagnosed in WCH from 2009 to 2013 to reflect the regional epidemiological profile of GEP-NETs.

RESULTS

GEP-NETs proportion in WCH increased 1.6-folds during past 5 years from 1.28/10(5) to 2.03/10(5) , P < 0.05. The average duration of symptom before diagnosis was 16.8 months. About 46.6% (115/248) of GEP-NETs were metastatic. Seventy-seven percent (190/248) of patients were over 40 years. Proportions of GEP-NETs from primary sites were rectum 30.6% (76/248), pancreas 23.4% (58/248), gastric 13.3% (33/248) and esophagus 11.3% (28/248). Proportions of insulinoma, vipoma and nonfunctional pancreatic neuroendocrine tumors (P-NETs) were 43.1% (25/58), 1.7% (1/58) and 55.2% (32/58) separately in the P-NETs.

CONCLUSIONS

There is a distinct epidemiologic profile between West China and western countries based on a single institution data. The delayed diagnosis reflects inadequate disease awareness of GEP-NETs and paucity of research funding.

Neuroendocrine tumor biomarkers: From monoanalytes to transcripts and algorithms

The management of neuroendocrine neoplasia remains a perplexing problem because of the lack of knowledge of the biology of the disease, its late presentation, the relative insensitivity of imaging modalities and a paucity of predictably effective treatment options. A critical limitation is posed by the lack of accurate biomarkers to guide management, monitor the efficacy of therapy and provide a prognostic assessment of disease progress. Currently utilized monoanalyte biomarkers (e.g. chromogranin, serotonin, pancreastatin etc.) exhibit variable metrics, poor sensitivity, specificity, and predictive ability and are rarely used to guide clinical decision making. A National Cancer Institute Neuroendocrine Tumor summit conference held in 2007 noted biomarker limitations to be a crucial unmet need in the management of neuroendocrine tumors. Nevertheless little progress has been made in this field until recently with the consideration of blood transcript analysis, circulating tumor cells and miRNA measurement. Given the complexity and multidimensionality of the neoplastic process itself, the heterogeneity of neuroendocrine tumors (NET) as well as the interaction of the tumor microenvironment, it is not unexpected that no single (monoanalyte) biomarker has proven to be effective. This deduction reflects the growing recognition that use of a monoanalyte to define a multidimensional disease process has inherent flaws. Logic dictates that no single measured parameter can capture the pathobiological diversity of neoplasia and monoanalytes cannot define the multiple variables (proliferation, metabolic activity, invasive potential and metastatic propensity) that constitute tumor growth. Thus far, most biomarkers whether in tissue or blood/urine have been single analytes with varying degrees of sensitivity and specificity and in general have failed to exhibit robust metrics or lacked methodological rigor. Neuroendocrine (NE) disease represents an area of biomarker paucity since the individual biomarkers (gastrin, insulin etc) are not widely applicable to the diverse types of NE neoplasia (NEN). Broad spectrum markers such as CgA have limitations in sensitivity, specificity and reproducibility. This review serves to provide a general background of the evolution of NET biomarkers. It provides an assessment of their current and past usage and limitations in assessing their diagnostic, pathologic and prognostic aspects in respect of NET. It provides a view of the changing methodology of biomarker development and the application of biomathematical analyses to redefining detection and treatment. Finally, it presents a description and consensus on current advances in transcript analysis, miRNA measurement and circulating tumor cell identification.

Elevated Plasma Pancreastatin, but Not Chromogranin A, Predicts Survival in Neuroendocrine Tumors of the Duodenum

BACKGROUND

Neuroendocrine tumors (NETs) of the duodenum are rare, heterogeneous, and often indolent neoplasms. We hypothesized that elevated pancreastatin levels are an indicator of a poor prognosis in well-differentiated duodenal NETs.

STUDY DESIGN

Data from patients diagnosed with a primary duodenal NET were analyzed. Patients that underwent esophogogastroduodenoscopy, endoscopic ultrasound, or exploratory surgery to localize their neoplasm and whose tumors were confirmed histologically were included.

RESULTS

Eighty-four patients were diagnosed with duodenal NETs from January 1991 to January 2014. Seventy-five percent and 21% of patients had their tumor localized by esophogogastroduodenoscopy and endoscopic ultrasound, respectively. The remaining 4% were localized during exploratory surgery. The 5-year Kaplan-Meier survival rate for the entire cohort (N = 84) was 80%. Survival sorted by normal vs abnormal pancreastatin level was statistically significant (p < 0.0001). Five-year survival rates were 94% and 37% for normal and abnormal pancreastatin, respectively. In contrast, survival sorted by normal vs abnormal plasma chromogranin A level was not statistically significant (p = 0.24).

CONCLUSIONS

Patients with primary duodenal NETs have high 5-year survival rates. Serial monitoring of plasma pancreastatin levels can identify patients who have a poor prognosis.

The clinical utility of a novel blood-based multi-transcriptome assay for the diagnosis of neuroendocrine tumors of the gastrointestinal tract

OBJECTIVES

Current monoanalyte blood-based biomarkers for the diagnosis and follow-up of neuroendocrine tumors (NETs) do not achieve satisfactory metrics of sensitivity and specificity. We report the sensitivity and selectivity of the PCR-based test, the NETest, to detect tumors with reference to other benign and malignant gastrointestinal diseases.

METHODS

A total of 179 cases (gastrointestinal tumors: n=81; pancreatic disease: n=98) were prospectively collected and assessed using the NETest or chromogranin A (CgA) to determine metrics for detecting small intestinal and pancreatic NETs.

RESULTS

For intestinal carcinoids, the accuracy of the NETest was 93% (all NETs positive and 3 (12%) colorectal tumors were positive). CgA was positive in 80%, but 29% (n=7) of colorectal cancers were CgA positive. For pancreatic disease, the NETest accuracy was 94% (96% NETs positive, 2 (6%) of intraductal papillary mucinous neoplasms (IPMNs) were positive). The accuracy of CgA was 56% (29% of pancreatic NETs were CgA positive). Overall, the NETest was significantly more sensitive than CgA for the detection of small intestinal (area under the curve 0.98 vs. 0.75 P<0.0001) and pancreatic NETs (0.94 vs. 0.52, P<0.0001). NETest scores were elevated (P<0.05) in extensive disease and were more accurate (76-80%) than CgA levels (20-32%). The metrics of the multianalyte NETest met the performance criteria proposed by the National Institutes of Health for biomarkers, whereas CgA measurement did not.

CONCLUSIONS

This study demonstrates that a blood-based multianalyte NET gene transcript measurement of well-differentiated small intestinal and pancreatic neuroendocrine tumor disease is sensitive and specific and outperforms the current monoanalyte diagnostic strategy of plasma CgA measurement.

The status of neuroendocrine tumor imaging: from darkness to light?

Diagnostic imaging plays a pivotal role in the diagnosis, staging, treatment selection and follow-up for neuroendocrine tumors. The available diagnostic strategies are morphologic imaging, including computed tomography, magnetic resonance imaging (MRI) and ultrasound techniques, and molecular imaging, including scintigraphy with (111)In-pentetreotide and positron emission tomography with (68)Ga-DOTA-peptides, (18)F-DOPA and (11)C-5-HTP. A combination of anatomic and functional techniques is routinely performed to optimize sensitivity and specificity. The introduction of diffusion-weighted MRI and dynamic contrast-enhanced techniques represents a promising advance in radiologic imaging, whereas new receptor-binding peptides, including somatostatin agonists and antagonists, represent the recent most favorable innovation in molecular imaging. Future development includes the short-term validation of these techniques, but in extension also a more comprehensive multilevel integration of biologic information pertaining to a specific tumor and patient, possibly encompassing genomic considerations, currently evolving as a new entity denoted 'precision medicine'. The ideal is a diagnostic sequence that captures the global status of an individual's tumor and encompasses a multidimensional characterization of tumor location, metabolic performance and target identification. To date, advances in imagery have focused on increasing resolution, discrimination and functional characterization. In the future, the fusion of imagery with the parallel analysis of biological and genomic information has the potential to considerably amplify diagnosis.

Primary Epithelial Neuroendocrine Tumors of the Retroperitoneum

Neuroendocrine tumors are either epithelial or neural in origin. Neuroendocrine tumors of the retroperitoneum are mostly metastatic. Primary epithelial neuroendocrine tumors of the retroperitoneum are exceedingly rare. We describe a case of a retroperitoneal tumor that was discovered incidentally during exploratory laparotomy for small-bowel obstruction. Histopathologic and immunochemical analyses of the biopsied mass were consistent with an epithelial neuroendocrine tumor. The tumor was subsequently removed and final analyses confirmed the initial diagnosis. No evidence of lymph nodes or paraganglia were found within the tumor on histologic examination. Extensive evaluation did not reveal any other primary or metastatic lesions. Therefore, the diagnosis of primary epithelial neuroendocrine tumor of the retroperitoneum was made. The literature is reviewed and discussed. To date, this is only the fifth reported case of primary epithelial retroperitoneal neuroendocrine tumor. Although extremely rare, the possibility of such diagnosis should be included in the differential diagnosis of a retroperitoneal tumor.

A PCR blood test outperforms chromogranin A in carcinoid detection and is unaffected by proton pump inhibitors

A critical requirement in neuroendocrine tumor (NET) management is a blood biomarker test that is sensitive, specific and reproducible. We evaluated a PCR-based 51-transcript signature to detect tumors, compared it with chromogranin A (CgA) and examined the confounding effect of proton pump inhibitors (PPIs), which cause falsely elevated CgA levels. The multigene signature was evaluated in two groups. Group 1: 125 prospectively collected NETs: gastroenteropancreatic NETs (n=91, including 42 pancreatic and 40 small intestinal), carcinoids of unknown primary (n=18) and other sites (n=16). Group 2: prospectively collected non-NET patients receiving PPIs (>1 month; dyspepsia, n=19; GERD, n=6; and pancreatitis, n=4) and 50 controls. All samples were analyzed by PCR (marker genes) and ELISA (DAKO-CgA). Sensitivity comparisons included χ(2), non-parametric measurements, and receiver operating characteristic (ROC) curves. Group 1: 123 NETs were PCR-positive (98.4%) compared with 50 (40%) CgA-positive (χ(2)=97.3, P<10(-26)). Significant differences (P<0.001) were noted between pancreas: PCR 95% vs CgA 29.2% (P<10(-9)) and small intestine: 100 vs 58% (P<10(-4)). The multigene test was elevated in all grades (G1-G3), in both local and disseminated disease, and was not normalized by somatostatin analog therapy. It was also elevated in 97% of CgA normal NETs. Group 2: PPI administration increased CgA in 83% and CgA was elevated in 26% of controls. PCR values were not elevated in either group. PCR performance metrics were as follows: sensitivity 98.4%, specificity 100%, positive predictive value 100%, negative predictive value 97.8%, and the ROC-derived area under the curve (AUC) was 0.997. These were significantly better than CgA (all metrics <60%; AUC, 0.54; Z-statistic, 10.44, P<0.0001). A 51-panel multigene blood transcript analysis is significantly more sensitive than plasma CgA for NET detection and is unaffected by acid suppression therapy.

Review article: the investigation and management of gastric neuroendocrine tumours

BACKGROUND

Gastric carcinoids (GCs) or neuroendocrine tumours (NETs) are increasingly identified at endoscopy, and account for 0.6-2% of all gastric polyps identified. The SEER database in the US has demonstrated a rising incidence of gastric NETs amongst all NETs; from 2.2% between 1950 and 1969 to 6.0% between 2000 and 2007.

AIM

To review the literature and assist clinicians in managing patients with GCs.

METHODS

A literature search was conducted through MEDLINE using search terms: gastric, carcinoid, neuroendocrine tumour, therapy, endoscopy, mucosal resection, submucosal dissection. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles.

RESULTS

There are three types of GCs with important epidemiological, pathophysiological, histological and endoscopic differences that affect prognosis and management. Type 1 and 2 GCs develop in the context of hypergastrinaemia that originates from achlorhydria in atrophic gastritis and a gastrinoma, respectively. Type 3 GCs occur sporadically and independent of gastrin. The histological type, grade and Ki67 index are used to determine prognosis and direct clinical management. Type 1 GCs >1 cm in size and type 2 GCs should be assessed for invasion beyond the submucosa with EUS prior to endoscopic resection with EMR or ESD. Type 3 GCs should be managed as per recommendations for gastric adenocarcinoma. The treatment of advanced disease is multimodal.

CONCLUSIONS

Patients with gastric carcinoids should be discussed in a specialist neuroendocrine tumour multidisciplinary meeting to ensure all treatment options are explored in localised and advanced disease. Areas of controversy exist that need further research.

Detection of neuroendocrine tumours in the small intestines using contrast-enhanced multiphase Ga-68 DOTATOC PET/CT: the potential role of arterial hyperperfusion

Background

Interpretation of small intestinal neuroendocrine tumours (NETs) by Ga-68 DOTATOC PET/CT can be difficult. The potential benefit of arterial hyperperfusion for the detection of NETs was evaluated.

Methods

Between 2006 and 2009, 320 consecutive Ga-68 DOTATOC PET/CT examinations, performed for NETs, revealed 40 lesions suggesting intestinal NETs in 25 patients. Two groups of lesions were distinguished: epigastric lesions evaluable in the arterial and venous CT scan (Group 1) and hypogastrial lesions evaluable in the venous CT scan only (Group 2). Lesions were jointly rated by two radiologists and a nuclear medicine physician. Maximum standard uptake values (SUVmax) of lesions and background were assessed. The reference standard was histology (available for 28 lesions) or follow-up (for a mean of 22.9 months).

Results

PET detected all suspicious lesions but was false positive in 3 lesions. In Group 1 the arterial scan performed significantly better than the venous scan (p = 0.008). Diagnostic performance was better in Group 1 than in Group 2 (p < 0.001). SUVmax of true positive lesions were significantly higher than background SUVmax (p < 0.001) and SUVmax of false positive lesions (p = 0.005).

Conclusions

The arterial phase of multiphase Ga-68 DOTATOC PET/CT might improve the localization of intestinal NETs and, thereby, improve the overall diagnostic accuracy of this modality in the assessment of intestinal NETs by adding information about lesion perfusion not available when only venous CT is performed.

Neuroendocrine tumor biomarkers: current status and perspectives

The identification of accurate harbingers of disease status and therapeutic efficacy are critical requirements in precise diagnosis and effective management. Initially, tissue analysis was regarded as ideal but invasive strategies represent risk compared with peripheral blood sampling. Thus far, most biomarkers, whether in tissue or blood/urine, have been single analytes with varying degrees of sensitivity and specificity. Some analytes have not exhibited robust metrics or have lacked methodological rigor. Neuroendocrine disease represents an area of dire biomarker paucity since the individual biomarkers (gastrin, insulin, etc.) are not widely applicable to the diverse types of neuroendocrine neoplasia. Broad-spectrum markers such as chromogranin A have limitations in sensitivity, specificity and reproducibility. Monoanalytes cannot define the multiple variables (proliferation, metabolic activity, invasive potential, metastatic propensity) that constitute tumor growth. The restricted status of the neuroendocrine neoplasia field has resulted in a lack of comprehensive knowledge of the molecular and cellular biology of the disease, with tardy application of innovative technology. This overview examines limitations in current practice and describes contemporary viable strategies under evaluation, including the identification of novel analytes (gene transcripts, microRNA), circulating tumor cells and metabolic imaging agents that identify disease. Novel requirements are necessary to develop biomathematical algorithms for synchronous calibration of multiple molecular markers and predictive nomograms that interface biological variables to delineate disease progress or treatment efficacy. Optimally, the application of novel techniques and amalgamations of multianalyte assessment will provide a personalized molecular disease signature extrapolative of neuroendocrine neoplasia status and likelihood of progression and predictive of therapeutic opportunity.

Single-photon emission computed tomography tracers in the diagnostics of neuroendocrine tumors

Different imaging strategies have been developed targeting the peculiar features of neuroendocrine tumors (NETs). Metabolic characteristics and receptor expression on the tumor surface have been studied, and expertise and knowledge are increasing as a result of the implementation of fusion imaging and the development of more detailed positron emission tomography tracers. Scintigraphic study of NETs is the most diffused and convenient technique for evaluating patients suspected to have NETs.

Sequelae and survivorship in patients treated with (131)I-MIBG therapy

Background:

¹³¹I-meta-iodobenzylguanidine (¹³¹I-MIBG) has been in therapeutic use since 1980s. Newer treatment modalities are emerging for neuroendocrine tumours (NETs) and chromaffin cell tumours (CCTs), but many of these do not yet have adequate long-term follow-up to determine their longer term efficacy and sequelae.

Methods:

Fifty-eight patients with metastatic NETs and CCTs who had received ¹³¹I-MIBG therapy between 2000 and 2011 were analysed. Survival and any long-term haematological or renal sequelae were investigated.

Results:

In the NET group, the overall median survival and median survival following the diagnosis of metastatic disease was 124 months. The median survival following the commencement of ¹³¹I-MIBG was 66 months. For the CCT group, median survival had not been reached. The 5-year survival from diagnosis and following the diagnosis of metastatic disease was 67% and 67.5% for NETs and CCTs, respectively. The 5-year survival following the commencement of ¹³¹I-MIBG therapy was 68%. Thirty-two patients had long-term haematological sequelae: 5 of these 32 patients developed haematological malignancies. Two patients developed a mild deterioration in renal function.

Conclusion:

Long follow up of ¹³¹I-MIBG therapy reveals a noteable rate of bone marrow toxicities and malignancy and long term review of all patients receiving radionuclide therapies is recommended.

Outcome of surgery for ileojejunal neuroendocrine tumors

PURPOSE

Neuroendocrine tumors (NET) of the ileum/jejunum are rare and may require different treatment options to provide long-term survival. The purpose of the study was to evaluate the outcome of surgery for ileojejunal NET.

METHODS

A database of patients that underwent surgery for ileojejunal NETs between 1999 and 2010 was retrospectively analyzed regarding the clinical characteristics, surgical therapy, survival and prognostic factors.

RESULTS

Only six of 97 patients with ileojejunal NET who underwent surgery had localized tumors (stage I/II), 29 had lymph node involvement (stage III) and 62 had distant metastases (stage IV) at the initial presentation. All stage I/II tumors were cured, in comparison to 69% of stage III and 0% of stage IV tumors (p = 0.01). Palliative surgery in combination with sequential multimodal treatment regimens resulted in a 5-year survival rate of 63% in patients with stage IV tumors. A multivariate analysis showed that incomplete resection (HR 2.87; CI 1.18-6.98; p = 0.04) and distant metastases (HR 5.39; 95% CI 1.23-23.57; p = 0.02) were associated with worse disease-specific survival.

CONCLUSIONS

Localized and regionally restricted ileojejunal NETs have an excellent prognosis after surgical treatment. Although stage IV tumors cannot be cured, an aggressive surgical approach in combination with medical or interventional treatment can provide long-term survival.

Theranostics: evolution of the radiopharmaceutical meta-iodobenzylguanidine in endocrine tumors

Since 1981, meta-iodobenzylguanidine (MIBG), labeled with (131)I and later (123)I, has become a valuable agent in the diagnosis and therapy of a number of endocrine tumors. Initially, the agent located pheochromocytomas and paragangliomas (PGLs), both sporadic and familial, in multiple anatomic sites; surgeons were thereby guided to excisional therapies, which were previously difficult and sometimes impossible. The specificity in diagnosis has remained above 95%, but sensitivity has varied with the nature of the tumor: close to 90% for intra-adrenal pheochromocytomas but 70% or less for PGLs. For patients with neuroblastoma, carcinoid tumors, and medullary thyroid carcinoma, imaging with radiolabeled MIBG portrays important diagnostic evidence, but for these neoplasms, use has been primarily as an adjunct to therapy. Although diagnosis by radiolabeled MIBG has been supplemented and sometimes surpassed by newer scintigraphic agents, searches by this radiopharmaceutical remain indispensable for optimal care of some patients. The radiation imparted by concentrations of (131)I-MIBG in malignant pheochromocytomas, PGLs, carcinoid tumors, and medullary thyroid carcinoma has reduced tumor volumes and lessened excretions of symptom-inflicting hormones, but its value as a therapeutic agent is being fulfilled primarily in attacks on neuroblastomas, which are scourges of children. Much promise has been found in tumor disappearance and prolonged survival of treated patients. The experiences with therapeutic (131)I-MIBG have led to development of new tactics and strategies and to well-founded hopes for elimination of cancers. Radiolabeled MIBG is an exemplar of theranostics and remains a worthy agent for both diagnosis and therapy of endocrine tumors.

Chromogranin A (CgA) as poor prognostic factor in patients with small cell carcinoma of the cervix: results of a retrospective study of 293 patients

BACKGROUND

Small cell carcinoma of the cervix (SCCC) is a very rare tumor. Due to its rarity and the long time period, there is a paucity of information pertaining to prognostic factors associated with survival. The objective of this study was to determine whether clinicopathologic finings or immunohistochemical presence of molecular markers predictive of clinical outcome in patients with SCCC.

METHODOLOGY AND FINDINGS

We retrospectively reviewed a total of 293 patients with SCCC (47 patients from Cancer Center of Sun Yat-sen University in china, 71 patients from case report of china journal, 175 patients from case report in PubMed database). Of those 293 patients with SCCC, the median survival time is 23 months. The 3-year overall survival rates (OS) and 3-year disease-free survival rates (DFS) for all patients were 34.5% and 31.1%, respectively. Univariate and multivariate analysis showed that FIGO stage (IIb-IV VS I-IIa, Hazard Ratio (HR) = 3.08, 95% confidence interval (CI) of ratio = [2.05, 4.63], P<0.001), tumor mass size (≥ 4 cm VS <4 cm, HR = 2.37, 95% CI = [1.28, 4.36], P = 0.006) and chromogranin A (CgA) (Positive VS Negative, HR = 1.81, 95% CI = [1.12, 2.91], P = 0.015) were predictive of poor prognosis. CgA stained positive was found to be highly predictive of death in early-stage (FIGO I-IIa) patient specifically.

CONCLUSIONS

Patients with SCCC have poor prognosis. FIGO stage, tumor mass size and CgA stained positive may act as a surrogate for factors prognostic of survival. CgA may serve as a useful marker in prognostic evaluation for early-stage patients with SCCC.

Nuclear medicine techniques for the imaging and treatment of neuroendocrine tumours

Nuclear medicine plays a pivotal role in the imaging and treatment of neuroendocrine tumours (NETs). Somatostatin receptor scintigraphy (SRS) with [(111)In-DTPA(0)]octreotide has proven its role in the diagnosis and staging of gastroenteropancreatic NETs (GEP-NETs). New techniques in somatostatin receptor imaging include the use of different radiolabelled somatostatin analogues with higher affinity and different affinity profiles to the somatostatin receptor subtypes. Most of these analogues can also be labelled with positron-emitting radionuclides that are being used in positron emission tomography imaging. The latter imaging modality, especially in the combination with computed tomography, is of interest because of encouraging results in terms of improved imaging quality and detection capabilities. Considerable advances have been made in the imaging of NETs, but to find the ideal imaging method with increased sensitivity and better topographic localisation of the primary and metastatic disease remains the ultimate goal of research. This review provides an overview of the currently used imaging modalities and ongoing developments in the imaging of NETs, with the emphasis on nuclear medicine and puts them in perspective of clinical practice. The advantage of SRS over other imaging modalities in GEP-NETs is that it can be used to select patients with sufficient uptake for treatment with radiolabelled somatostatin analogues. Peptide receptor radionuclide therapy (PRRT) is a promising new tool in the management of patients with inoperable or metastasised NETs as it can induce symptomatic improvement with all Indium-111, Yttrium-90 or Lutetium-177-labelled somatostatin analogues. The results that were obtained with [(90)Y-DOTA(0),Tyr(3)]octreotide and [(177)Lu-DOTA(0),Tyr(3)]octreotate are even more encouraging in terms of objective tumour responses with tumour regression and documented prolonged time to progression. In the largest group of patients receiving PRRT, treated with [(177)Lu-DOTA(0),Tyr(3)]octreotate, a survival benefit of several years compared with historical controls has been reported.

Serum and ascites chromogranin-A in patients with metastatic neuroendocrine tumors

OBJECTIVES

Ascites secondary to neuroendocrine tumor metastases may arise from a variety of mechanisms. Our aim was to measure serum and ascitic chromogranin-A (CgA) to help determine whether ascites resulted from intraperitoneal/retroperitoneal disease burden or from other carcinoid complications such as congestive heart failure or portal hypertension.

METHODS

Patients with metastatic neuroendocrine tumors and ascites were identified. Chromogranin-A was obtained and measured from both serum and ascites. The causes of carcinoid ascites was categorized into 2 groups: high intraperitoneal or retroperitoneal disease burden (ie, peritoneal metastases and/or lymphatic obstruction; n = 12, group 1) or other organ-specific carcinoid complications such as CHF or portal hypertension (n = 12, group 2).

RESULTS

An ascites CgA/serum CgA ratio greater than 1 was more likely to be found in group 1 (P = 0.01). This ratio produced 100% sensitivity and 75% specificity for ascites secondary to peritoneal metastases and/or lymphatic obstruction.

CONCLUSIONS

An ascites CgA/serum CgA ratio greater than 1 produces excellent accuracy in predicting peritoneal metastases and/or retroperitoneal disease as the cause of ascites in the setting of metastatic carcinoid. This test may play a role in the earlier identification of those patients who may be well served by aggressive management.

Skin manifestations of hormone-secreting tumors

Endocrine and metabolic diseases, besides affecting other organs, can result in changes in cutaneous function and morphology and can lead to a complex symptomatology. Dermatologists may see some of these skin lesions first, either before the endocrinologist, or even after the internist or specialist has missed the right diagnosis. Because some skin lesions might reflect a life-threatening endocrine or metabolic disorder, identifying the underlying disorder is very important, so that patients can receive corrective rather than symptomatic treatment. In this issue, we will review various hormone-secreting tumors, including pituitary disorders (Cushing's syndrome and acromegaly), hyperthyroidism, glucagonoma, carcinoid syndrome, mastocytosis, and hyperandrogenism. We will focus on clinical manifestations, mainly cutaneous, followed by a brief discussion on how to make the diagnosis of each condition in addition to treatment options.

[Fulminant duodenal bleeding as first manifestation of a neuroendocrine carcinoma of the pancreatic head]

CASE REPORT

A 73-year-old male patient presented with upper gastrointestinal bleeding. The reason was an arterial hemorrhage from a duodenal tumor that could only be stopped by an angiographic intervention. In the further staging, there was evidence for a neuroendocrine carcinoma of the pancreatic head with infiltration of the duodenum and hepatic metastases. Due to good differentiation (G1) a systemic biotherapy with octreotide LAR was induced. After recurrent bleeding with arrosion of a branch of the superior mesenteric artery, a duodenum-preserving pancreatic head resection was performed. Afterwards, the systemic therapy was changed to a palliative chemotherapy with streptozotocin and 5-fluorouracil due to local progression of the disease and a Ki-67 index of 4% in the primary tumor.

CONCLUSION

In about 0.7% of patients with neuroendocrine tumors, the lesion is located in the pancreas. At this site these entities are very heterogeneous. The majority are nonfunctional tumors without secretion of bioactive substances and the associated symptoms. About 60% of the patients present with advanced metastasized disease. The therapy depends on the local spread and histological grading as well as symptoms of the patient. The only curative option represents surgical resection. However, even in a palliative situation, there can be benefit for the patient in case of a tumor mass reduction of > 90%. Alternative therapies in the palliative situation are somatostatin analogs, a classic systemic chemotherapy, or locoregional interventional procedures.

Epidemiology of neuroendocrine cancers in an Australian population

OBJECTIVE

The aim was to explore incidence, mortality and case survivals for invasive neuroendocrine cancers in an Australian population and consider cancer control implications.

METHODS

Directly age-standardised incidence and mortality rates were investigated from 1980 to 2006, plus disease-specific survivals.

RESULTS

Annual incidence per 100,000 increased from 1.7 in 1980-1989 to 3.3 in 2000-2006. A corresponding mortality increase was not observed, although numbers of deaths were low, reducing statistical power. Increases in incidence affected both sexes and were more evident for female lung, large bowel (excluding appendix), and unknown primary site. Common sites were lung (25.9%), large bowel (23.3%) (40.9% were appendix), small intestine (20.6%), unknown primary (15.0%), pancreas (6.5%), and stomach (3.7%). Site distribution did not vary by sex (p = 0.260). Younger ages at diagnosis applied for lung (p = 0.002) and appendix (p < 0.001) and older ages for small intestine (p < 0.001) and unknown primary site (p < 0.001). Five-year survival was 68.5% for all sites combined, with secular increases (p < 0.001). After adjusting for age and diagnostic period, survivals were higher for appendix and lower for unknown primary site, pancreas, and colon (excluding appendix).

CONCLUSIONS

Incidence rates are increasing. Research is needed into possible aetiological factors for lung and large-bowel sites, including tobacco smoking, and excess body weight and lack of exercise, respectively; and Crohn's disease as a possible precursor condition.

Epidemiological study of gastroenteropancreatic neuroendocrine tumors in Japan

BACKGROUND

There have been few epidemiological studies on gastroenteropancreatic neuroendocrine tumors (GEP-NETs) in Japan.

METHODS

We examined the epidemiology of GEP-NETs [pancreatic endocrine tumors (PETs) and gastrointestinal neuroendocrine tumors (GI-NETs)] in Japan in 2005 using a nationwide stratified random sampling method.

RESULTS

A total of 2,845 individuals received treatment for PETs. Prevalence was estimated as 2.23/100,000 with an annual onset incidence of 1.01/100,000. Non-functioning tumor (NF)-PET constituted 47.4%, followed by insulinoma (38.2%) and gastrinoma (7.9%). Distant metastases were reported in 21% patients with NF-PETs and occurred more frequently as tumor size increased (>2 cm). Multiple endocrine neoplasia type 1 (MEN-1) was detected in 10% of PETs but only in 6.1% of NF-PETs. NF-PETs were detected incidentally by physical examination in 24% patients. In 2005, an estimated 4,406 patients received treatment for GI-NETs. Prevalence was estimated as 3.45/100,000, with an annual onset incidence of 2.10/100,000. The locations of GI-NETs varied: foregut, 30.4%; midgut, 9.6%; and hindgut, 60.0%. Distant metastases were observed in 6%. Lymph node metastases occurred more frequently as tumor size increased (>1 cm). The frequency of MEN-1 complications was 1%. Physical examination revealed GI-NETs in 44% patients. The frequency of symptomatic GI-NETs was 3.4%. Interestingly, 77.1% of patients with foregut GI-NETs had type A gastritis.

CONCLUSION

Our results show there are large differences in GEP-NETs between Japan and Western nations, primarily due to differences in the presence of MEN-1 in NF-PETs and the location, symptomatic status, and prevalence of malignancy in GI-NETs.

Efficacy of using a standard activity of (131)I-MIBG therapy in patients with disseminated neuroendocrine tumours

PURPOSE

The aim of this analysis was to evaluate the response to standard activity of (131)I-meta-iodobenzylguanidine (MIBG) in patients with disseminated neuroendocrine tumours (NETs), comparing overall survival of patients with symptomatic response, tumour size (as assessed by CT) and relevant plasma tumour markers.

METHODS

A retrospective review of patients who had undergone (131)I-MIBG treatment between March 2001 and December 2006 was carried out. The administered activity of (131)I-MIBG was 5.5 GBq (NETs) and 7 GBq (phaeochromocytoma). Three cycles of treatment were planned with an interval of 10-12 weeks. A pre-therapy scan with (123)I-MIBG was performed to ascertain appropriate biodistribution.

RESULTS

Thirty-eight patients were identified. Only two patients developed significant bone marrow suppression. Symptomatic response: data were available in 37 of 38 patients: 15 patients had improved symptoms, 19 had no improvement in symptoms and 3 were asymptomatic. In those with a symptomatic response, the median overall survival was 58 months vs no response of 20.0 months (p = 0.001). CT response: in those with stable disease, the median overall survival was 58 months compared with progressive disease of 16.0 months. The difference between these groups was significant (p = 0.006). Hormonal response: this was available in only 20 of 38 patients. The median overall survival was the same for patients that had increased hormone levels and patients that had stable/decreased hormone levels (48 months).

CONCLUSION

Standard activity (131)I-MIBG is well tolerated. Symptomatic response to treatment is a significant predictor of overall survival. Whilst CT response also appears to predict survival, hormonal levels do not appear to correlate with survival.