Clinical Profiles and Survival Outcomes of Patients With Well-Differentiated Neuroendocrine Tumors at a Health Network in New South Wales, Australia: Retrospective Study

Incidence, prevalence, and survival trends for neuroendocrine neoplasms in Victoria, Australia, from 1982 to 2019: Based on site, grade, and region

AIMS

Neuroendorcine neoplasms (NENs) are rare tumors characterised by variable biology and delayed diagnosis. Several population studies have reported a marked increased incidence over time. The objectives of this analysis were to describe within Victoria (the second largest Australian state, 6.4 Million) the trends for NENs incidence/survival over nearly 38 years (1982-2019), and regional differences in survival.

METHODS

All NEN cases were identified from the Victorian Cancer Registry over four time periods: 1982-1989, 1990-1999, 2000-2009, and 2010-2019. Data collected included primary tumor site, histological grade, gender, overall survival (OS), and place of residence. Incidence data were analyzed with the generation of annual standardized rates (ASR). OS was assessed for the entire cohort and between geographical regions.

RESULTS

The overall NEN population (1982-2019) included 8,106 patients: over 60% grade 1/2 NENs, especially small bowel and colorectal. The number of new diagnoses increased over three-fold over time for the overall cohort and by tumoral categories. The ASR increased similarly, especially pancreatic NENs (4.3-fold) and differed between genders. The 5-year OS rates and median OS increased over time for the overall cohort: from 52% to 67% (p < 0.001). OS was greater for NEN patients residing in major cities relative to regional/remote areas (p = 0.01).

CONCLUSION

This population-wide analysis with over 38 years of data has confirmed the international trends of the increased incidence, prevalence, and OS of NEN patients regardless of primary site or histological grade. The analysis also observed a difference in survival outcome in rural/remote versus urban areas.

Comparable survival benefit of local excision versus radical resection for 10- to 20-mm rectal neuroendocrine tumors

OBJECTIVE

The optimal surgical management for 10- to 20-mm rectal neuroendocrine tumors (RNET) is still a matter of debate. This study aimed to explore the optimal surgical approach for 10- to 20-mm RNET by comparing the outcomes between local excision and radical resection.

METHOD

We extracted clinicopathological information of 10- to 20-mm RNET from the Surveillance, Epidemiology, and End Results (SEER) database. The 1:2 propensity score matching (PSM) method was used to balance the imbalanced baseline covariates (P < 0.05) between the local excision group and radical resection group. A Cox proportional hazards model was used to identify the risk factors associated with cancer-specific survival (CSS) and overall survival (OS).

RESULT

A total of 531 RNET patients 10-20 mm in size were included. Patients receiving radical resection had larger tumor sizes (P < 0.001), higher T stages (P < 0.001), higher N stages (P < 0.001), higher M stages (P = 0.002) and higher grades (P = 0.041). For 10-20 mm RNET patients, radical resection had no survival benefit compared with local excision (CSS: HR = 2.048, 95% CI 0.553-7.576, P = 0.283; OS: HR = 1.090, 95% CI 0.535-2.219, P = 0.813). After 1:2 PSM, there was no significant difference between local excision and radical resection. Radical resection still had no survival benefit over local excision (CSS: HR = 0.449, 95% CI 0.050-4.022, P = 0.474; OS: HR = 1.408, 95% CI 0.488-4.061, P = 0.527). In a multivariate analysis of CSS, age >60 years old (P = 0.005), tumour size 14-20 mm (P = 0.011) and M1 stage (P < 0.001) were identified as independent prognostic factors for worse CSS. In multivariate analysis of OS, age>60 years (P＜0.001), male sex (P = 0.007), black race (P = 0.016), and T2/T3/T4 stage (P = 0.007) were significantly associated with worse OS. N stage was not an independent predictive factor for CSS and OS.

CONCLUSION

This study revealed that for 10- to 20-mm RNET patients, there was no survival benefit for radical resection compared with local excision, which suggested that local excision may be an adequate treatment for these patients.

Factors associated with worse outcomes for colorectal neuroendocrine tumors in radical versus local resections

Background

Colorectal neuroendocrine tumors (NETs) are the most common NETs of the gastrointestinal tract. Due to the rarity, colorectal NETs are understudied and are not clearly understood. Our study sought to identify the factors associated with worse outcomes for colorectal NETs following resection.

Methods

We identified patients diagnosed with colorectal NETs [2004-2014] who underwent resection from the National Cancer Data Base. Non-NETs were excluded. Overall survival (OS) was evaluated using the Kaplan Meier method. Cox proportional hazards and logistic regression models were used to assess factors associated with radical versus local resection, OS and LOS.

Results

A total of 7,967 colon and 11,929 rectal NETs were analyzed. The majority of colon (93.4%) and rectal (89.1%) NETs underwent radical and local resection respectively. The 5-year OS was 69% and 92% for colon and rectal NETs respectively. Older age (OR 1.45, CI 1.37-1.53) and clinical stage 4 (OR 9.91, CI 4.56-21.52) were associated with higher odds for colonic radical resection. Lowest median income quartile (OR 1.41, CI 1.21-1.64) and African Americans (OR 1.26, CI 1.07-1.49) experienced higher mortality for colon and rectal NETs respectively.

Conclusions

Racial minority and low-income patients experience worse outcomes for colorectal NETs following resection.