A multicenter observational study on Medication-Related Osteonecrosis of the Jaw (MRONJ) in advanced cancer and myeloma patients of a cancer network in North-Western Italy / Un estudio observacional multicéntrico sobre osteonecrosis relacionada con medicamentos de la mandíbula (MRONJ) en pacientes con cáncer avanzado y mieloma de una red contra el cáncer en el noroeste de Italia

ABSTRACT

Background: Incidence of Medication-Related Osteonecrosis of the Jaw (MRONJ) related to cancer and myelomatreatments is undetermined, with scarce data varying from 2 to 7.8/million/year in limited investigated popula-tions. A 9-years [2009-2018] regional-wide survey was conducted, deploying the North-Western Italy Cancer Net-work (“Rete Oncologica Piemonte e Valle d’Aosta”), to assess number and main characteristics of MRONJ casesamong myeloma/cancer patients, within a population of 4.5 million inhabitants.Material and Methods: MRONJ cases were collected retrospectively from January 2009 to June 2015; from July2015 to December 2018, data were collected prospectively. Number of new MRONJ cases per year, underlyingdisorder, drug(s) administered, treatment duration, site and onset timing of MRONJ were detailed.Results: 459 MRONJ cases were identified. Primary diseases were breast cancer (46%), prostate cancer (21%),myeloma (19%), and other types of carcinoma (14%). Patients received antiresorptive treatment either alone (399;88.47%) or in combination with biological agents (52; 11.53%); 8 patients (1.7%) received only antiangiogenicdrugs. Zoledronic acid [388] and denosumab [59] were the most frequently administered drugs. Mandible was involved in 296 (64,5%) cases. Number of new MRONJ cases was stable from 2009 to 2015, with a mean of 51.3 casesper year (raw incidence 11.6/million/year), declining in the 2016-2018 years to 33.3 cases per year (raw incidence7.5/million/year).Conclusions: With such discrepancy of cases overtime being partially explicable, number of new MRONJ cases peryear are consistent with those observed in a previous study [2003-2008] in the same region, being instead higher thanthose reported in other populations.(AU)