Case report of a patient with initially inoperable well-differentiated midgut neuroendocrine tumor (WDNT) -- PRRT and long-acting somatostatin analogs as the neoadjuvant therapy.

A 43-year-old man was admitted to Surgery Department because of abdominal pain, vomiting, weight loss and flushes. Computed tomography (CT) examination revealed upper and middle abdomen tumor of about 110 x 110 mm. Histopathological analysis of the tissues obtained during the exploratory laparotomy confirmed WDNT (well-differentiated neuroendocrine tumor according to the WHO classification 2000). The patient received 5 doses of chemotherapy without any response. A positive result of ^99mTc-[EDDA/Hynic] Octreotate scintigraphy (SRS) gave the possibility of PRRT (peptide receptor radionuclide therapy). The patient was treated with the total dose of 400 mCi of ⁹⁰Y-DOTA-TATE. CT performed after the PRRT revealed regression of the tumor size to 72 x 94 mm. A decrease of CgA level and release of symptoms were also observed. Aiming at the removal of the considerable diminished tumor the patient was qualified for the second laparotomy. "Cytoreduction" surgery with partial excision of the tumor was performed. Additionally tumor-affected appendix was removed. The second focus of WDNT (according to the WHO classification 2000) with Ki67 < 1% was found in the appendix. Pathologists confirmed the above-mentioned lesions as independent (an extremely rare clinical situation). The following treatment with long-acting somatostatin analogs and 300 mCi of ⁹⁰Y-DOTA-TATE resulted in further regression of the tumor size to 25 x 35 mm. Consecutive laparotomy is considered. If complete tumor removal might be achieved is an open question. The above case report shows the efficacy of combined therapy with the use of "hot" and "cold" somatostatin analogs not only in controlling the symptoms of the disease but also in obtaining tumor size regression making surgical intervention possible. Such a neoadjuvant therapy seems to be a promising tool in the management of patients with initially inoperable neuroendocrine tumors. [ABSTRACT FROM AUTHOR]