e18564 Background: Telephone consultation has emerged as an alternative method for outpatient medical follow-up during the COVID-19 pandemic, reinforcing the necessary distancing measures. However, there are multiple factors that the medical team must contend with, which could limit the monitoring of patients. Methods: We retrospectively analyzed the remote medical consultation database of a university-based oncology referral center in northeast Mexico. The telephone calls were made from the medical center by specialized health personnel. The data obtained correspond to the monitoring conducted over six months. Results: We included 1,140 patients in the analysis, of which 79% were women and 21% were men; the median age was 55 years. All individuals had a pathology-confirmed diagnosis of cancer. The main oncological diagnoses were breast, cervix, and prostate cancer which corresponded to 46, 13, and 7% of the cases, respectively. Ninety-four percent of cases corresponded to cancer surveillance, while the remaining 6% were receiving active oncological treatment, administered orally. Ninety-three percent of the patients were from the city of Monterrey and its metropolitan area, 6% came from the rest of the municipalities of the state of Nuevo Leon, and 1% were from other states of the Mexican Republic. Ninety-eight percent of the patients had a public health insurance as a method of coverage for health services, while 2% received care through private health insurance. At remote follow-up, only 53% of the patients responded to the telephone calls, none of them reported a diagnosis or any symptom of SARS-CoV-2 infection. Among the 536 patients who had a telephone communication failure, 68% did not respond to the call after 4 attempts, while in 32% of these cases the number provided by the patient was incorrect or non-existent. Conclusions: The high rates of failure to establish telephone communication documented in our population of patients with cancer is a worrying phenomenon. As the COVID-19 pandemic progresses worldwide, we must seek to establish measures to optimize logistics for more effective remote communication, to achieve the best possible outcomes.

503 Background: Neuroendocrine tumors (NETs) are infrequent neoplasms that originate in the neuroendocrine cells of the embryological endoderm. Few data exist about the epidemiology and clinical characteristics of these tumors in the Mexican population. Methods: We performed a retrospective analysis of patients with pathology-confirmed NET treated at an Oncology Reference Center in North-East Mexico from 2010 to 2019. Clinical characteristics were recorded and an evaluation of overall survival (OS) using the Kaplan-Meier method was performed. Results: Fifty-three patients were included in the final analysis. The mean age at diagnosis was 54 +/- 16.36 years and 53% were men. Primarily affected sites were the gastroenteropancreatic tract [GEP] (47%), lung and mediastinum (21%), unknown primary (21%), and others (11%). Regarding the clinical stage at presentation, 22.6% of patients with NETs had localized disease, while 22.6% had regional spread and 54.7% were considered to have metastatic disease at diagnosis. Median OS was 42 months for all patients with NETs. In the GEP group, the median OS was 64 months, whereas for the lung/ mediastinum group was 8 months and for the unknown primary group was 5 months. Median OS stratified by stage was as follows: Localized disease: Not reached (NR), locoregional (20 months), and metastatic disease (8 months). Conclusions: To our knowledge, this is the first study published in English literature reporting the clinical characteristics and survival of Mexican patients with NETs. It is necessary to expand the information regarding these neoplasms to improve access of these patients to standard treatments and therefore improve their outcomes.