Peritoneal metastases in patients with neuroendocrine neoplasms: a challenging site of metastases with clinical and prognostic implications.

PURPOSE: Peritoneal metastases (PM) of neuroendocrine neoplasm (NEN) origin are identified with increasing frequency and exert a significant effect on quality of life and clinical status of the patients. The aim of this study was to identify the characteristics and the prognostic significance of PM in patients with NENs. METHODS: A retrospective analysis of the data of patients from two tertiary referral centers was performed. We defined a control group of age- and gender-matched NEN patients with comparable stage IV disease but no PM. RESULTS: We analysed 70 patients (41 females) with PM. Small intestine was the most common primary NEN site (87.1%). PM prevalence was 10.3%. Forty-four patients presented with synchronous PM, whereas 26 developed metachronous PM. The majority of patients had other concomitant metastases (50 hepatic, 6 lung and 12 bone metastases). Twelve patients developed intestinal obstruction. After PM diagnosis, 76% of patients received treatment with somatostatin analogues while six patients (8.6%) were treated with peptide receptor radionuclide therapy (PRRT). The median progression-free survival (PFS) in the PRRT-treated group was 15 months (95% CI 2-28). Median overall survival (OS) in the PM group was 142 months [95% CI 71-213] while it was not reached in the control group. CONCLUSION: Peritoneal metastases show low prevalence among NEN patients and are most likely to develop in patients with small intestinal NENs and advanced metastatic disease. The presence of PM does seem to be associated with a negative prognostic impact on OS of NEN patients and their identification and prompt treatment is of major importance.

Idiopathic central diabetes insipidus in a large cohort of patients: the hypopituitarism ENEA rare observational (HEROS) study.

Central Diabetes Insipidus (CDI) is mainly associated with structural pathologies of the hypothalamic-pituitary area. Etiologies underlying CDI are identified in most patients, however idiopathic CDI is reported in 13-17% of cases after excluding other etiologies. The Hypopituitarism ENEA Rare Observational Study (HEROS study) retrospectively collected data of patients with idiopathic CDI from 14 pituitary centers in 9 countries. The cohort included 92 patients (59 females 64%), mean age at diagnosis was 35.4 ± 20.7 years, and a mean follow up of 19.1 ± 13.5 years following CDI diagnosis. In 6 women, diagnosis was related to pregnancy. Of 83 patients with available data on pituitary imaging, 40(48%) had normal sellar imaging, and 43(52%) had pathology of the posterior pituitary or the stalk, including loss of the bright spot, posterior pituitary atrophy or stalk enlargement. Anterior pituitary hormone deficiencies at presentation included hypogonadism in 6 (6.5%) patients (5 females), and hypocortisolism in one; during follow-up new anterior pituitary deficiencies developed in 6 patients. Replacement treatment with desmopressin was given to all patients except one, usually with an oral preparation. During follow up, no underlying disease causing CDI was identified in any patient. Patients with idiopathic CDI following investigation at baseline are stable with no specific etiology depicted during long-term follow-up.