Efficacy and Safety Evaluation of Tarlatamab in Advanced Extrapulmonary Neuroendocrine Carcinoma Patients

Inclusion Criteria: \- Subject has provided informed consent prior to initiation of any study specific activities/procedures. * Age ≥19 years at the time of signing the informed consent. * Histologically confirmed relapsed/refractory extra-pulmonary neuroendocrine carcinoma. Neuroendocrine carcinoma includes small cell carcinoma, large cell carcinoma, and mixed histology of neuroendocrine and other histology (e.g., adenoneuroendocrine carcinoma, urothelial carcinoma with neuroendocrine component). In patients with prostate cancer, treatment-emergent neuroendocrine carcinoma (initially adenocarcinoma, but transdifferentiate into neuroendocrine carcinoma after androgen deprivation therapy) will be permitted. * Cohort 1 (gastrointestinal and pancreaticobiliary cohort): cancers originated from stomach, esophagus, small intestine, colorectal, pancreas, or bile ducts. * Cohort 2 (genitourinary cohort): cancers originated from prostate, bladder, ureter, urethra, or kidney. * Subject has progressed or recurred following 1 platinum-based regimen: * documented first disease progression must be during or following first-line platinum-based systemic chemotherapy. For patients with prostate cancer, especially in cases with treatment-emergent neuroendocrine carcinoma, platinum-based chemotherapy will not need to be the first line therapy. * patients who received treatment for localized disease who recur are eligible * patients who received adjuvant Platinum-Etoposide (EP) after rese…