When possible, surgery to completely remove small intestinal neuroendocrine tumors (siNETs) is always recommended. However, in cases where the tumor has spread and cannot be cured completely, it is unclear whether a surgical removal of the primary tumor only is reasonable. In this situation, current guidelines from the European Neuroendocrine Tumor Society (ENETS) recommend surgery only for patients who have symptoms like intestinal blockage or bleeding, or are at risk of such complications. For patients without symptoms, it is still unclear whether removing the main tumor improves overall outcomes and prevents future problems. Studies evaluating this type of surgery on survival show conflicting results. These studies often do not separate patients with symptoms from those without, and they overlook other important factors like the amount of cancer in the liver and nearby tissues. Due to these uncertainties, the rarity of siNETs and many factors that can affect outcomes, like age, overall health, or other current treatments, conducting a high-quality study to answer this question is challenging. To address this, the present Europe-wide study is being planned. This study aims to determine if resecting the main tumor improves the 10-year overall survival and reduces risks like intestinal blockages or blood flow issues compared to no surgery in patients without symptoms. The study will also assess other outcomes, such as how long patients stay free from disease progression, the risks of surgery, and prognostic factors for long-term survival. This international collaboration among neuroendocrine tumor referral centers will provide robust evidence to guide clinical practice and update treatment guidelines for siNETs.
Study Type
OBSERVATIONAL
Enrollment
3,200
Histopathological review
UHI Berne
Bern, Switzerland
To evaluate the 10-year overall survival of non-curative metastatic siNET with or without primary tumor resection at initial diagnosis in asymptomatic patients.
For the survival analysis, Kaplan-Meier method will be used to estimate overall survival at 10 years for patients with and without primary tumor resection.
Time frame: 10 years follow-up
To evaluate the progression-free survival of non-curative metastatic siNET with or without primary tumor resection at initial diagnosis in asymptomatic patients.
For the survival analysis, Kaplan-Meier method will be used to estimate overall survival at 10 years for patients with and without primary tumor resection.
Time frame: 10 years follow-up
To examine the risk of small intestinal obstruction with or without palliative primary tumor resection
To account for additional established prognostic information, univariable and multivariable Cox proportional hazards regression will be used.
Time frame: 10 years follow-up
To examine the risk of small intestinal hypoperfusion with or without palliative primary tumor resection
To account for additional established prognostic information, univariable and multivariable Cox proportional hazards regression will be used.
Time frame: 10 years follow-up
To evaluate the morbidity of palliative primary tumor resection
To account for additional established prognostic information, univariable and multivariable Cox proportional hazards regression will be used.
Time frame: 10 years follow-up
To evaluate the mortality of palliative primary tumor resection
To account for additional established prognostic information, univariable and multivariable Cox proportional hazards regression will be used.
Time frame: 10 years follow-up
To assess prognostic factors for long-term survival
The following prognostic information will be taken into account: age, sex, ECOG, presence of second malignancy, and adjusted for characteristics of the siNET (Ki-67 index, number of siNETs, lymph node metastases, TBS, extrahepatic metastases, CgA level, 5-HIAA level, carcinoid heart disease, and use of other treatments), with results presented as adjusted hazard ratios (HRs) and 95% CI.
Time frame: 10 years follow-up
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.