This is a retrospective study. The analysis includes patients with advanced neuroendocrine cancer (NEN) treated with systemic therapy, because of inoperable primary tumor or/and metastasis, clinical, imaging, biochemical disease progression and no standard method of treatment hormone overproduction symptoms. The data of patients with advanced NEN with histopathological confirmation is collected from medical records. The progression-free survival (PFS), overall survival (OS) and influence of various factors on survival will be estimated. The research will be conducted for above 3 years on planned group 1500 patients. The aim of the study is to estimate median OS and PFS in advanced NEN patients treated with different schedule of systemic treatment.

This is a retrospective study. The analysis includes patients with advanced neuroendocrine cancer (NEN) treated with systemic therapy, because of inoperable primary tumor or/and metastasis, clinical, imaging, biochemical disease progression and no standard method of treatment hormone overproduction symptoms. Systemic treatment including: somatostatin receptor analogues, molecular targeted therapy (sunitinib and everolimus), chemotherapy and peptide radioisotope therapy (Peptide Receptor Radionuclide Therapy). The data of patients with advanced NEN with histopathological or/and clinical or/and biochemical confirmation is collected from medical records. Neuroendocrine cancer from digestive system, respiratory system and another rarely occurring cancer including cancer connected with genetic syndromes like: MEN1, MEN2, VHL, NF1, SDHx will be included. The progression-free survival (PFS), overall survival (OS) and influence of various factors on survival will be estimated. Analyzed factors: age, sex, ethnicity, specific symptoms at the time of diagnosis, carcinoid heart disease, level of 5HIAA in DZM, level of CgA, liver test, size of tumor, cell differentiation of tumor based on Ki-67 index, liver metastases. The research will be conducted for above 3 years since July 2019 till December 2022 on planned group 1500 patients. The aim of the study is to estimate median OS and PFS in advanced NEN patients treated with different schedule of systemic treatment. The second goal is to create clinical practice recommendation based on potential prognostic factors of OS and PFS due to type of therapy in different NEN subgroups.

Inclusion Criteria:

• Adults ≥18 years old, male or female,
• Patients with histopathological confirmation of advanced neuroendocrine cancer (NEN),
• Patients with NETG1, NETG2 based on Ki-67,
• Patients with diagnosed NEN, who did not receive prior treatment and were qualified to systemic treatment,
• Patients with advanced NEN who previously received first-line systemic therapy or second-line systemic therapy,
• Patients with advanced, inoperable NEN cancer before the treatment, during the treatment and after the treatment regardless of lines of systemic therapy,
• Patients with diagnosed NEN and performance status (PS) ≤3 according to ECOG/WHO classification, who received systemic therapy.

Exclusion Criteria:

• Patients without histopathological confirmation of neuroendocrine carcinoma (NEN),
• Patients with diagnosed another type of cancer or benign tumor confirmed in histopathological examination,
• Patients treated prior with intention to treat (ITT),
• Patients with residual disease in further clinical follow-up without active systemic treatment,
• Patients with advanced, progressive and poor performance status, who were disqualified from further systemic treatment,
• Patients, who finished treatment during first month or their further disease process was unknown.

The study is planned on a group 1500 patients with advanced, histopathologically confirmed neuroendocrine neoplasms (NEN) treated with different schedule of systemic treatment including: somatostatin receptor analogues, molecular targeted therapy (sunitinib or everolimus), chemotherapy using different therapeutic regimens and peptide receptor radioisotope therapy (Peptide Receptor Radionuclide Therapy).

Research on NEN patients will include the following groups of patients:

1. NEN from digestive system,
2. respiratory system;
3. Other NEN tumours including PPGL, cancer of known primary and very rare NEN tumours like gynecological or urological primary NET.
4. NEN connected with genetic syndromes like: MEN1, MEN2, VHL, NF1, SDHx.