Serum chromogranin A levels for the diagnosis and follow-up of well-differentiated non-functioning neuroendocrine tumors

The hidden potential of glycomarkers: Glycosylation studies in the service of cancer diagnosis and treatment

Changes in the glycosylation process appear early in carcinogenesis and evolve with the growth and spread of cancer. The correlation of the characteristic glycosylation signature with the tumor stage and the appropriate therapy choice is an important issue in translational medicine. Oncologists also pay attention to extracellular vesicles as reservoirs of new cancer glycomarkers that can be potent for cancer diagnosis/prognosis. In this review, we recall glycomarkers used in oncology and show their new glycoforms of improved clinical relevance. We summarize current knowledge on the biological functions of glycoepitopes in cancer-derived extracellular vesicles and their potential use in clinical practice. Is glycomics a future of cancer diagnosis? It may be, but in combination with other omics analyses than alone.

Chromogranin B in blood serum of patients with neuroendocrine tumors

Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms from cells of the diffuse neuroendocrine system. Chromogranin B (CgB) is an acidic protein of the granin family, which can be used to detect the tumours of neuroendocrine nature. Analysis of levels and evaluation of the diagnostic efficiency of CgB in the blood serum of patients with NETs of various localizations. Patients with NETs (n=121) without specific treatment were examined. In the study were presented next localizations: 74 - pancreas, 20 - stomach, 12 - large intestine, 15 - other localizations (lungs, mammary gland, prostate gland, NETs with unidentified primary). 54 practically healthy donors were examined as control group. The determination of CgB in blood serum was performed with ELISA method on BEP 2000 analyzer using a standardized test system Human Chromogranin B (USCN, China). CgB levels in common NET group (median 18.9 ng/mL) were statistically significantly higher than in the control group (8.8 ng/mL). The highest median was obtained in group of intestinal NETs (21.2 ng/ml), which exceeded the median of the control group by more than 2.4 times. According to ROC analysis in the common NET group relative to the control group, the area under the curve AUC was 0.88 (95% CI 0.83-0.929). According to cut-off level of CgB - 15.8 ng/ml, the diagnostic sensitivity was 69.4%, with a specificity of 96.3%. The highest diagnostic sensitivity was in the group of the intestinal NETs (75.0%) and pancreas (71.2%). The study showed the significance of CgB as a potential biochemical marker of NETs with various localizations, alternative to CgA.

Use of Chromogranin A for Monitoring Patients With Pancreatic Neuroendocrine Neoplasms

OBJECTIVE

We aimed to assess the role of serum chromogranin A (CgA) in monitoring disease status and treatment response in patients with pancreatic neuroendocrine neoplasms (pNENs).

METHODS

We included posttherapy pNENs patients with measured serum CgA levels who underwent 68Ga-labeled tetraazacyclododecanetetraacetic acid-peptide positron emission tomography (PET) imaging between April 2017 and January 2020. Serum CgA levels were determined by enzyme-linked immunosorbent assay. Tumor response was assessed according to the PET response evaluation criteria in solid tumors.

RESULTS

Seventy-seven patients with 101 events were included in this study. Serum CgA levels were significantly higher in patients with active disease and metastasis. The optimal cutoff values for CgA for active and metastatic pNENs diagnosis after treatment were 52.39 (77.8% sensitivity, 80.7% specificity) and 60.18 ng/mL (73.9% sensitivity, 73.1% specificity), respectively. Based on 18 patients with serial CgA measurements and PET imaging, the optimal changes in CgA levels for predicting disease remission and progression were a 28.5% decrease (71.4% sensitivity, 88.2% specificity) and a 21.0% increase (100.0% sensitivity, 75.0% specificity), respectively.

CONCLUSIONS

We concluded that serum CgA levels are associated with disease status and treatment response and may thus provide a helpful biomarker for the monitoring and clinical management of patients with pNENs.

A "Watch and Wait" Strategy Involving Regular Endoscopic Surveillance Is Safe for Many Patients with Small, Sporadic, Grade 1, Non-Ampullary, Non-Functioning Duodenal Neuroendocrine Tumours

INTRODUCTION

Duodenal neuroendocrine tumours (d-NETs) are rare but are increasing in incidence. Current ENETS guidelines advocate resection of all localized d-NETs. However, "watch and wait" may be appropriate for some localized, small, grade 1, non-functioning, non-ampullary d-NETs. We evaluated whether patients with such d-NETs who chose "watch and wait" involving regular endoscopic surveillance had equivalent disease-related outcomes to patients undergoing endoscopic or surgical resection.

METHODS

Retrospective review of patients with histologically confirmed d-NETs at Liverpool ENETS Centre of Excellence 2007-2020.

RESULTS

Sixty-nine patients were diagnosed with d-NET of which 50 were sporadic, non-functioning, non-ampullary tumours. Patient treatment groups were similar in terms of age, gender, and tumour location and grade, but unsurprisingly, larger tumours (median diameter 17 mm [p < 0.0001]) were found in the surgically treated group. Five patients underwent surgical resection with no evidence of tumour recurrence or disease-related death. Twelve patients underwent endoscopic resection (ER), with 1 local recurrence detected during follow-up. Thirty patients (28 with d-NETs ≤10 mm) underwent "watch and wait" with resection only if tumours increased in size. The d-NETs in 28/30 patients remained stable or decreased in size over a median 27 months (IQR: 15-48, R: 3-98). In 7 patients, the d-NET was completely removed by avulsion during diagnostic biopsy and was not seen at subsequent endoscopies. Only 2 patients showed increased d-NET size during surveillance, of whom only one was fit for ER. No NET-related deaths were documented during follow-up.

CONCLUSIONS

All of the localized, ≤10 mm, grade 1, non-functioning, non-ampullary d-NETs in this cohort behaved indolently with very low risks of progression and no tumour-related deaths. "Watch and wait," therefore, appears to be a safe alternative management strategy for selected d-NETs.

Limited role of Chromogranin A as clinical biomarker for pancreatic neuroendocrine tumors

BACKGROUND

Serum Chromogranin A (CgA) is widely used as a biomarker for pancreatic neuroendocrine tumors (PanNETs). The aim of this study was to investigate the value of CgA as a diagnostic and prognostic marker for well-differentiated PanNETs.

METHODS

Patients with well-differentiated PanNET and a baseline CgA measurement, between 2011 and 2016 were reviewed. The diagnostic value was determined by comparing CgA values from patients with PanNETs to those with other pancreatic neoplasms and healthy controls. The Kaplan-Meier method was used to investigate the CgA prognostic significance.

RESULTS

Ninety-nine patients met inclusion criteria. As a diagnostic marker, CgA had a sensitivity of 66%, specificity of 95%, and overall accuracy of 71%. The use of PPIs was associated with a higher CgA level (p = 0.015). When excluding patients on PPIs, CgA accuracy in distinguishing PanNETs from other pancreatic neoplasms was 66%, the sensitivity and specificity were 60% and 75% respectively. Elevated CgA (p = 0.004), Ki67% (p < 0.001), tumor grade (p < 0.001) and stage of disease (p = 0.036) were associated with disease-specific survival.

CONCLUSION

CgA has a limited role as a diagnostic biomarker for well-differentiated PanNETs. An elevated CgA level may have prognostic value but its role should be further investigated with respect to other known pathological factors.

Chromogranin A in the Follow-up of Gastroenteropancreatic Neuroendocrine Neoplasms: Is It Really Game Over? A Systematic Review and Meta-analysis

OBJECTIVES

Little is known about chromogranin A (CgA) during follow-up of gastroenteropancreatic neuroendocrine neoplasms. We hypothesized that serial CgA monitoring might be useful for the assessment of tumor progression, and we performed a systematic review of the literature and meta-analysis.

METHODS

A bibliographical search was performed in PubMed using "chromogranin A" and "neuroendocrine tumors" and "follow-up" and "biomarker" to identify all pertinent articles published in the last 10 years.

RESULTS

Eight studies were included in current meta-analysis. Chromogranin A as a follow-up marker shows sensitivity between 46% and 100% and specificity between 68% and 90%. The meta-analysis results showed an overall accuracy of 84% (95% confidence interval [CI], 81-86.6), a cumulative sensitivity of 74.6% (95% CI, 61.9-85.4), and a cumulative specificity of 84.7% (95% CI, 81.3-87.7). These data indicate that circulating CgA has a better overall accuracy in the follow-up setting; it can be used to rule the diagnosis of recurrence/progression in, rather than to rule it out.

CONCLUSIONS

Chromogranin A is more reliable when used to monitor disease progression and response to treatment and for the early detection of recurrence after treatment rather than in the diagnostic setting. It is more sensible to use this marker in those cases where the initial values were impaired.

Prognostic value of chromogranin A in patients with GET/NEN in the pancreas and the small intestine

The aim of this study was to evaluate the clinical usefulness of the chromogranin A (CgA) determination in patients with neuroendocrine neoplasms (NENs) of the digestive system and to analyse the association between concentration of the marker and progression-free survival (PFS) and overall survival (OS). Serum concentrations of CgA were determined before the treatment in 131 patients with NENs, including patients with tumours located in the pancreas, the small intestine, caecum, appendix and in the colon. No significant associations were identified in CgA concentrations between the control group and patients with NENs in appendix and colon. In patients with NENs of the pancreas and NENs of the small intestine and caecum, increased CgA levels were associated with lymph node involvement, distant metastases and a baseline liver involvement. Analyses revealed significantly higher CgA concentrations in patients with active disease compared to those without symptoms of NEN. In patients with NENs of the pancreas, CgA concentration was correlated with tumour grade and Ki67. Significantly higher CgA levels were also found in patients who died compared to those who lived. Analyses of PFS and OS revealed that CgA concentration was not a prognostic factor in patients with NENs of the pancreas. In patients with NENs of the small intestine and caecum, increased CgA concentrations are independent, poor prognostic factors for both PFS and OS. In conclusion, in patients with NENs in pancreas, CgA levels are associated with disease progression, while in patients with NENs in small intestine and caecum, its concentration is a predictive indicator for PFS and OS.