The largest public Lynch syndrome registry in Argentina: description of our 10-year experience

ANTELO M; MILITO, D,; GOLUBICKI, M; CARBALLIDO, M.; MENDEZ, G; ISEAS, S.; BARUGEL, M.; HIRMAS, SM; SALANOVA, R.; MIKOLAITIS, V; CABANNE, A.; BARTELLINI, MA; CISTERNA, D; ROCA, E

San Pablo

Congreso; International Society for Gastrointestinal Hereditary Tumours - 6th Biennial Meeting; 2015

International Society for Gastrointestinal Hereditary Tumours

Purpose: although only a minority of the total cases, Lynch syndrome(LS) represents around 150 cases of colorectal cancer (CRC) per year inArgentina, which through timely investigation and intervention couldpotentially be prevented. The optimal management of this syndrome involves specializedfamilial cancer units and registries that facilitate a multidisciplinaryapproach, with a demonstrated improvement in both the incidence of CRC and theoverall survival in affected families. Here we describe the structure, themanagement and the patient´s characteristics of the largest public LynchSyndrome Registry in Argentina, located in a public metropolitan hospital inBuenos Aires, along with our improvements during the last 10 years.Metholodology: a review of all the registered families since 1999 wasundertaken. We evaluated family´s characteristics, molecular tests andsurveillance colonoscopies results, and we analyzed the increase over time ofthe number of families recruited and of the molecular tests done.  Results: we recruited 648 families with Amsterdam (92=14%),Bethesda (501=77%) or CRC<70 (55=8.5%) criteria for LS attended at theOncology Section of our hospital. Interestingly, 193 (30%) reached only theBethesda 1 criteria. During the period 2009-2014, in which two gastroenterologistsfull-time were incorporated to the  registry, we recruited 490 families, 3times more than during the 1999-2008 period. 279 (43%) of our index patientshad   no social insurance. Immunohistochemistry (IHC) formismatch-repair (MMR) proteins was started at our hospital in 2010, and sincethen 428 (66%) patients were analyzed. 266 (41%) cases did microsatelliteinstability (MSI) analysis in the private context, since no one does it freelyin Argentina. During 2014 our Hospital has become the first and only publiccenter that does MSI, and we have evaluated already 36 cases. We actually have21 (3,2%) confirmed Lynch syndrome families, 14 (2%) Lynch-like syndromepatients, 8 (5%) Familial CRC syndrome X, 230 (35%) cases with an intact MMR,260 (40%) patients that still need IHC and/or MSI, and 115 (18%) cases with MMRdeficiency that still need to be genetically studied but have no possibilitybecause these tests are not done freely in Argentina. Lastly, we have analyzedso far 919 colonocopies in the context of CRC surveillance, 519 from our indexpatients and 327 from their first-degree relatives. We identified 37 (5.7%)high risk adenomas and 22 (3.4%) CRC´s; of these 18 (82%) were early tumors(Stage I-II) and only 3 (13,5%) were stage III and 1 (4,5%) stage IV. Conclusion:we have achieved with great effort and dedication of our human resource, alongwith funding and managerial support from the CONICET and the Argentine NationalCancer Institute, one of the largest LS Registries in South America. Our registryalso represents the first public hospital in our country to do IHC and MSI forLS freely. Nevertheless, we still must keep on working to achieve morepermanent human resource and the realization of more genetic tests, so we canfinally democratize sequencing and reach the whole community, withoutdistinction of socio-economic status.