Resection of Primary Gastrointestinal Neuroendocrine Tumor Among Patients with Non-Resected Metastases Is Associated with Improved Survival: A SEER-Medicare Analysis

Morbidity and Outcomes of Primary Tumor Management in Patients with Widely Metastatic Well-Differentiated Small Bowel Neuroendocrine Tumors

BACKGROUND

The benefit of primary tumor resection in distant metastatic small bowel neuroendocrine tumors (SBNETs) is controversial, with treatment-based morbidity not well-defined. We aimed to determine the impact of primary tumor resection on development of disease-specific complications in patients with metastatic well-differentiated SBNETs.

PATIENTS AND METHODS

A retrospective analysis was performed of patients diagnosed with metastatic well-differentiated jejunal/ileal SBNETs at a single tertiary care cancer center from 1980 to 2016. Outcomes were compared on the basis of treatment selected at diagnosis between patients who underwent initial medical treatment or primary tumor resection.

RESULTS

Among 180 patients, 71 underwent medical management and 109 primary tumor resection. Median follow-up was 116 months. Median event-free survival did not differ between treatment approaches (log-rank p = 0.2). In patients medically managed first, 16/71 (23%) required surgery due to obstruction, perforation, or bleeding. These same complications led to resection at presentation in 31/109 (28%) surgically treated patients. Development of an obstruction from the primary tumor was not associated with disease progression/recurrence (HR 1.14, 95% CI 0.75-1.75) with all patients recovering postoperatively. Ongoing tumor progression requiring secondary laparotomy was associated with worse mortality (HR 7.51, 95% CI 3.3-16.9; p < 0.001) and occurred in 20/109 (18%) primary tumor resection and 7/16 (44%) initially medically treated patients.

CONCLUSIONS

Rates of event-free survival among patients with metastatic SBNETs do not differ on the basis of primary tumor management. The development of an obstruction from the primary tumor was not associated with worse outcomes with all patients salvaged. Regardless of initial treatment selected, patients with metastatic SBNET should be closely followed for early signs of primary tumor complications.

Impact of primary tumor resection and metastasectomy among gastroentero-pancreatic neuroendocrine tumors with liver metastases only on survival

BACKGROUND

Despite recommendations for primary tumor resection (PTR) with or without liver resection (LR) in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and isolated liver metastases, there are conflicting data for their impact on overall survival (OS).

METHODS

2320 patients with GEP-NETs and isolated liver metastases were identified from NCDB. Multiple imputations were used to accommodate missing data, and inverse probability of treatment weighting (IPTW) was conducted to minimize bias.

RESULTS

Patients with PTR had a greater OS than those without PTR (3-year rate of 88.6% vs. 69.9%, P < 0.001), which was preserved in the adjusted analysis (IPTW-adjusted HR = 0.387, 95% CI: 0.264-0.567; P < 0.001). Patients with LR had a greater OS than those without LR (3-year rate 87.7% vs. 75.2%, P = 0.003), which was also preserved in adjusted analysis (IPTW-adjusted HR = 0.450, 95% CI: 0.229-0.885; P = 0.021). Patients undergoing both PTR and LR had the greatest survival advantage than those with other surgical interventions (P < 0.001).

CONCLUSIONS

Either PTR or LR is associated with improved survival for GEP-NET patients with isolated liver metastases. However, there remains significant selection bias in the current study, and caution should be exercised when selecting patients for resection.

Disparities in Socioeconomic Factors Mediate the Impact of Racial Segregation Among Patients With Hepatopancreaticobiliary Cancer

BACKGROUND

Structural racism within the U.S. health care system contributes to disparities in oncologic care. This study sought to examine the socioeconomic factors that underlie the impact of racial segregation on hepatopancreaticobiliary (HPB) cancer inequities.

METHODS

Both Black and White patients who presented with HPB cancer were identified from the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database (2005-2015) and 2010 Census data. The Index of Dissimilarity (IoD), a validated measure of segregation, was examined relative to cancer stage at diagnosis, surgical resection, and overall mortality. Principal component analysis and structural equation modeling were used to determine the mediating effect of socioeconomic factors.

RESULTS

Among 39,063 patients, 86.4 % (n = 33,749) were White and 13.6 % (n = 5314) were Black. Black patients were more likely to reside in segregated areas than White patients (IoD, 0.62 vs. 0.52; p < 0.05). Black patients in highly segregated areas were less likely to present with early-stage disease (relative risk [RR], 0.89; 95 % confidence interval [CI] 0.82-0.95) or undergo surgery for localized disease (RR, 0.81; 95% CI 0.70-0.91), and had greater mortality hazards (hazard ratio 1.12, 95% CI 1.06-1.17) than White patients in low segregation areas (all p < 0.05). Mediation analysis identified poverty, lack of insurance, education level, crowded living conditions, commute time, and supportive income as contributing to 25 % of the disparities in early-stage presentation. Average income, house price, and income mobility explained 17 % of the disparities in surgical resection. Notably, average income, house price, and income mobility mediated 59 % of the effect that racial segregation had on long-term survival.

CONCLUSION

Racial segregation, mediated through underlying socioeconomic factors, accounted for marked disparities in access to surgical care and outcomes for patients with HPB cancer.

Racial Segregation Among Patients with Cholangiocarcinoma-Impact on Diagnosis, Treatment, and Outcomes

BACKGROUND

Racial segregation, an effect of historical marginalization, may impact cancer care and outcomes. We sought to examine the impact of racial segregation on the diagnosis, treatment, and outcomes of patients with cholangiocarcinoma (CCA).

PATIENTS AND METHODS

Data on Black and White patients with CCA were obtained from the linked SEER-Medicare database (2004-2015) and 2010 Census data. The index of dissimilarity (IoD), a validated measure of segregation, was used to assess Black-White disparities in stage disease presentation, surgery for localized disease, and cancer-specific mortality. Multivariable Poisson regression was performed, and competing risk regression analysis was used to determine cancer-specific survival.

RESULTS

Among 7480 patients with CCA, 90.2% (n = 6748) were White and 9.8% (n = 732) were Black. Overall, Black patients were more likely to reside in segregated areas compared with White patients (IoD, 0.42 vs. 0.38; p < 0.05). On multivariable Poisson regression, Black patients were more likely to present with advanced-stage disease [relative risk (RR) 1.17, 95% confidence interval (CI) 1.08-1.27; p < 0.001] and were less likely to undergo surgery for localized disease (RR 0.62, 95% CI 0.51-0.76; p < 0.001). Black patients also had worse cancer-specific survival (CSS) compared with White patients (median CSS: 4 vs. 8 months; p < 0.01). Black patients living in the highest areas of segregation had 40% increased hazard of mortality versus White patients residing in the lowest IoD areas (hazard ratio 1.40, 95% CI 1.10-1.80; p < 0.01).

CONCLUSION

Racial segregation, as a proxy for structural racism, had a marked effect on Black-White disparities among patients with CCA.

Surgical Approach to Liver Metastases in GEP-NET in a Tertiary Reference Center

Indications for liver resection in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NET) vary from liver resection with curative intent to tumor debulking or tissue sampling for histopathological characterization. With increasing expertise, the number of minimally invasive liver surgeries (MILS) in GEP-NET patients has increased. However, the influence on the oncological outcome has hardly been described. The clinicopathological data of patients who underwent liver resection for hepatic metastases of GEP-NET at the Department of Surgery, Charité—Universitätsmedizin Berlin, were analyzed. Propensity score matching (PSM) was performed to compare MILS with open liver surgery (OLS). In total, 22 patients underwent liver surgery with curative intent, and 30 debulking surgeries were analyzed. Disease-free survival (DFS) was longer than progression-free survival (PFS) (10 vs. 24 months), whereas overall survival (OS) did not differ significantly (p = 0.588). Thirty-nine (75%) liver resections were performed as OLS, and thirteen (25%) as MILS. After PSM, a shorter length of hospital stay was found for the MILS group (14 vs. 10 d, p = 0.034), while neither DFS/PFS nor OS differed significantly. Both curative intended and cytoreductive resection of hepatic GEP-NET metastases achieved excellent outcomes. MILS led to a reduced length of hospital, while preserving a good oncological outcome.

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are relatively uncommon malignancies, characterized as either functional or nonfunctional secondary to their secretion of biologically active hormones. A wide range of clinical behavior can be seen, with the primary prognostic indicator being tumor grade as defined by the Ki67 proliferation index and mitotic index. Surgery is the primary treatment modality for PNETs. While functional PNETs should undergo resection for symptom control as well as potential curative intent, nonfunctional PNETs are increasingly managed nonoperatively. There is increasing data to suggest small, nonfunctional PNETs (less than 2 cm) are appropriate follow with nonoperative active surveillance. Evidence supports surgical management of metastatic disease if possible, and occasionally even surgical management of the primary tumor in the setting of widespread metastases. In this review, we highlight the evolving surgical management of local and metastatic PNETs.

Risk and prognostic factors of brain metastasis in lung cancer patients: a Surveillance, Epidemiology, and End Results population‑based cohort study

BACKGROUND

Brain is a common metastasis site in lung cancer patients. However, homogeneous and heterogeneous risk/prognostic factors of brain metastasis for lung cancer patients have not been comprehensively elucidated. This study aimed to explore the brain metastasis risk and prognostic factors in lung cancer patients using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Lung cancer data were downloaded from SEER database to investigate risk factors for developing brain metastasis using logistic regression analysis. Univariate and multivariate Cox analyses were used to identify potential prognostic factors. Kaplan-Meier analysis was conducted to evaluate the survival. Propensity score matching was conducted to eliminate baseline differences between two groups.

RESULTS

A total of 10 818 (14.1%) patients with brain metastasis were diagnosed among 76 483 lung cancer patients. For non-small-cell lung carcinoma (NSCLC), distant liver/bone/lymph node metastases, higher T, N stages were risk factors. Black race, bone metastases and distant lymph node metastases and T4 were brain metastasis risk factors for SCLC patients. Cox analysis suggested that older age, male, primary lesion at main bronchus, liver/ bone/distant lymph node metastases, T2-4, N1-3, no surgery/chemotherapy/radiotherapy were associated with worse prognosis of NSCLC-brain metastasis patients. Age older than 80, liver/bone metastases, without radiotherapy and chemotherapy were associated with worse prognosis of SCLC-brain metastasis patients. Surgery of primary site could prolong the overall survival (OS) of NSCLC patients with brain metastasis, but not SCLC.

CONCLUSION

In this study, we analyzed the homogeneous and heterogeneous risk/prognostic factors of brain metastasis in lung cancer patients. What is more, our results showed that surgery of primary site was associated with longer OS of NSCLC patients with brain metastasis.

Primary tumor resection improves survival of gastrointestinal neuroendocrine carcinoma patients with nonresected liver metastases

BACKGROUND

The role of primary tumor resection (PTR) in the survival of gastrointestinal neuroendocrine carcinoma (GI-NEC) patients with liver metastases only remains poorly defined. Therefore, we investigated the impact of PTR on the survival of GI-NEC patients with nonresected liver metastases.

METHODS

GI-NEC patients with a liver-confined metastatic disease diagnosed between 2016 and 2018 were identified in the National Cancer Database. Multiple imputations by chained equations were used to account for missing data, and the inverse probability of treatment weighting (IPTW) method was used to eliminate selection bias. Overall survival (OS) was compared by adjusted Kaplan-Meier curves and log-rank test with IPTW.

RESULTS

A total of 767 GI-NEC patients with nonresected liver metastases were identified. Among all patients, 177 (23.1%) received PTR and had a significantly favorable OS before (median: 43.6 months [interquartile range, IQR, 10.3-64.4] vs. 8.8 months [IQR, 2.1-23.1], p < 0.001 in log-rank test) and after (median: 25.7 months [IQR, 10.0-64.4] vs. 9.3 months [IQR, 2.2-26.4], p < 0.001 in IPTW-adjusted log-rank test) the IPTW adjustment. Additionally, this survival advantage persisted in an adjusted Cox model (IPTW adjusted hazard ratio = 0.431, 95% confidence interval: 0.332-0.560; p < 0.001). The improved survival persisted in subgroups stratified by primary tumor site, tumor grade, and N stage, even in the complete cohort (excluding patients with missing data).

CONCLUSIONS

PTR led to improved survival for GI-NEC patients with nonresected liver metastases regardless of primary tumor site, tumor grade, and N stage. However, the decision for PTR should be made on an individualized basis following multidisciplinary evaluation.

Resection of the Primary Tumor Improves the Survival of Patients With Stage IV Gastric Neuroendocrine Carcinoma

Background

The prognostic prolongation effect of surgical resection in the management of gastric neuroendocrine carcinoma (GNEC) with distant metastases was still uncertain. The purpose of this study was to investigate the association of primary tumor resection (PTR) with outcomes in patients with stage IV GNEC.

Methods

This retrospective study analyzed patients with distant metastatic GNEC diagnosed between 2000 and 2018 and identified using the Surveillance, Epidemiology, and End Results (SEER) database. Patients were divided into PTR and non-PTR groups. The stabilized inverse probability of treatment weighting (IPTW) method was used to reduce the selection bias. Overall survival (OS) and cancer-specific survival (CSS) were estimated using the Kaplan–Meier method and log-rank test. Cox-regression analyses (uni- and multivariate) were performed to evaluate factors potentially influencing survival.

Results

A total of 126 patients with a median follow-up of 79 months were identified. Forty-four patients underwent PTR and 82 patients did not undergo surgery. After the IPTW approach, PTR improved the OS in patients with stage IV GNEC (median OS 12 vs. 6 months, P = 0.010). The 1- and 3-year OS for patients with or without PTR were 43.8% and 34.5%, and 27.9% and 6.5%, respectively. The median CSS was 12 months for patients undergoing PTR and 6 months for those who did not. The 1 and 3-year CSS for patients with or without PTR were 45.1% and 37.0%, and 27.9% and 6.5%, respectively. In IPTW-adjusted Cox proportional hazards regression analysis, PTR was recognized as an independent factor for improved survival after the occurrence of distant metastatic disease [OS: hazard ratio (HR) = 0.305; 95% confidence interval (CI): 0.196, 0.475; and CSS: HR = 0.278; 95% CI: 0.171, 0.452].

Conclusion

PTR for stage IV GNEC contributes to a better prognosis compared with non-surgery. This study supported the resection of the primary tumor in patients with distant metastatic GNEC.

Survival According to Therapy Regimen for Small Intestinal Neuroendocrine Tumors

Introduction: Scarce data exist for therapy regimens other than somatostatin analogues (SSA) and peptide receptor radiotherapy (PRRT) for siNET. We analyzed real world data for differences in survival according to therapy. Patients and methods: Analysis of 145 patients, diagnosed between 1993 and 2018 at a single institution, divided in treatment groups. Group (gr.) 0: no treatment (n = 10), gr 1: TACE and/or PRRT (n = 26), gr. 2: SSA (n = 32), gr. 3: SSA/PRRT (n = 8), gr. 4: chemotherapy (n = 8), gr. 5: not metastasized (at diagnosis), surgery only (n = 53), gr. 6 = metastasized (at diagnosis), surgery only (n = 10). Results: 45.5% female, median age 60 years (range, 27–84). A total of 125/145 patients with a resection of the primary tumor. For all patients, 1-year OS (%) was 93.8 (95%-CI: 90–98), 3-year OS = 84.3 (CI: 78–90) and 5-year OS = 77.5 (CI: 70–85). For analysis of survival according to therapy, only stage IV patients (baseline) that received treatment were included. Compared with reference gr. 2 (SSA only), HR for OS was 1.49 (p = 0.47) for gr. 1, 0.72 (p = 0.69) for gr. 3, 2.34 (p = 0.19) for gr. 4. The 5 y OS rate of patients whose primary tumor was resected (n = 125) was 73.1%, and without PTR was 33.3% (HR: 4.31; p = 0.003). Individual patients are represented in swimmer plots. Conclusions: For stage IV patients in this analysis (limited by low patient numbers in co. 3/4), multimodal treatment did not significantly improve survival over SSA treatment alone. A resection of primary tumor significantly improves survival.

Therapeutic strategies for gastroenteropancreatic neuroendocrine neoplasms: State-of-the-art and future perspectives

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have always been considered rare tumors, their incidence has risen over the past few decades. They represent a highly heterogeneous group of neoplasms with several prognostic factors, including disease stage, proliferative index (Ki67), and tumor differentiation. Most of these neoplasms express somatostatin receptors on the cell surface, a feature that has important implications in terms of prognosis, diagnosis, and therapy. Although International Guidelines propose algorithms aimed at guiding therapeutic strategies, GEP-NEN patients are still very different from one another, and the need for personalized treatment continues to increase. Radical surgery is always the best option when feasible; however, up to 80% of cases are metastatic upon diagnosis. Regarding medical treatments, as GEP-NENs are characterized by relatively long overall survival, multiple therapy lines are adopted during the lifetime of these patients, but the optimum sequence to be followed has never been clearly defined. Furthermore, although new molecular markers aimed at predicting the response to therapy, as well as prognostic scores, are currently being studied, their application is still far from being part of daily clinical practice. As they represent a complex disease, with therapeutic protocols that are not completely standardized, GEP-NENs require a multidisciplinary approach. This review will provide an overview of the available therapeutic options for GEP-NENs and attempts to clarify the possible approaches for the management of these patients and to discuss future perspectives in this field.

Effect of primary tumour resection without curative intent in patients with metastatic neuroendocrine tumours of the small intestine and right colon: meta-analysis

Background

Patients with small intestinal neuroendocrine tumours (siNETs) usually present with advanced disease. Primary tumour resection without curative intent is controversial in patients with metastatic siNETs. The aim of this meta-analysis was to investigate survival after primary tumour resection without curative intent compared with no resection in patients with metastatic siNETs.

Methods

A systematic literature search was performed, using MEDLINE® (PubMed), Embase®, Web of Science, and the Cochrane Library up to 25 February 2021. Studies were included if survival after primary tumour resection versus no resection in patients with metastatic siNETs was reported. Results were pooled in a random-effects meta-analysis, and are reported as hazard ratios (HRs) with 95 per cent confidence intervals. Sensitivity analyses were undertaken to enable comment on the impact of important confounders.

Results

After screening 3659 abstracts, 16 studies, published between 1992 and 2021, met the inclusion criteria, with a total of 9428 patients. Thirteen studies reported HRs adjusted for important confounders and were included in the meta-analysis. Median overall survival was 112 (i.q.r. 82–134) months in the primary tumour resection group compared with 60 (74–88) months in the group without resection. Five-year overall survival rates were 74 (i.q.r. 67–77) and 44 (34–45) per cent respectively. Primary tumour resection was associated with improved survival compared with no resection (HR 0.55, 95 per cent c.i. 0.47 to 0.66). This effect remained in sensitivity analyses.

Conclusion

Primary tumour resection is associated with increased survival in patients with advanced, metastatic siNETs, even after adjusting for important confounders.

Gastric neuroendocrine neoplasms: A review

Gastric neuroendocrine neoplasms (g-NENs) or neuroendocrine tumors are generally slow-growing tumors with increasing incidence. They arise from enterochromaffin like cells and are divided into four types according to clinical characteristic features. Type 1 and 2 are gastrin dependent, whereas type 3 and 4 are sporadic. The reason for hypergastrinemia is atrophic gastritis in type 1, and gastrin releasing tumor (gastrinoma) in type 2 g-NEN. The diagnosis of g-NENs needs histopathological investigation taken by upper gastrointestinal endoscopy. g-NENs are positively stained with chomogranin A and synaptophysin. Grading is made with mitotic index and ki-67 proliferation index on histopathological analysis. It is crucial to discriminate between types of g-NENs, because the management, treatment and prognosis differ significantly between subtypes. Treatment options for g-NENs include endoscopic resection, surgical resection with or without antrectomy, medical treatment with somatostatin analogues, netazepide or chemotherapy regimens. Follow-up without excision is another option in appropriate cases. The prognosis of type 1 and 2 g-NENs are good, whereas the prognosis of type 3 and 4 g-NENs are close to the prognosis of gastric adenocancer.