TY - THES ID - 138195711 TI - Tumours in Turner syndrome: a 10-year retrospective study in a tertiary referral centre in Belgium AU - Dejonckheere, Cas AU - Decallonne, Brigitte AU - Van Buggenhout, Griet AU - KU Leuven. Faculteit Geneeskunde. Opleiding Master in de geneeskunde (Leuven) PY - 2020 PB - Leuven KU Leuven. Faculteit Geneeskunde DB - UniCat UR - https://www.unicat.be/uniCat?func=search&query=sysid:138195711 AB - Background: Turner syndrome (TS), the most common sex chromosome abnormality in women, arises from partial or total loss of an X chromosome. Patients can suffer from a variety of well-researched comorbidities, including reproductive, cardiovascular, metabolic, and autoimmune disorders. Few studies have investigated the neoplasia risk in this patient group. Aim: To assess the general risk of neoplasia in TS women, and more specifically, the risk of gonadoblastoma and/or dysgerminoma in the subgroup with Y chromosome mosaicism, and to evaluate potential risk factors for neoplasia development, such as karyotype, metabolic and autoimmune comorbidity, and hormonal treatment. Design and setting: 10-year retrospective study in a tertiary referral centre in Belgium. Results: A total of 105 TS women were included. Six malignant tumours were detected in 5 (4.8%) patients (SIR = 0.6, 95% CI 0.2-1.0). In addition, 2 benign meningiomas were observed, resulting in a total of 3 (2.9%) tumours of the central nervous system (SIR = 19.9, 95% CI 4.0- 35.8). No breast cancer was noted. Various other benign neoplasms were discovered, with those arising from the skin being the most frequent. All women with Y chromosome mosaicism (n = 9; 8.6%) underwent a prophylactic gonadectomy. No gonadoblastoma nor dysgerminoma was detected. An association was found between any tumour type and autoimmune comorbidity (p = 0.02; r = 0.24). Conclusion: The overall risk of malignancy was not increased, but a different pattern of occurrence is apparent, with an increased risk of CNS and skin tumours and a decreased risk of breast cancer. Furthermore, this study questions the consensus that all TS women with Y chromosome mosaicism should undergo a prophylactic gonadectomy. ER -