BI07 Outcomes of oral squamous cell carcinoma following haematopoietic stem cell transplantation

Abstract Haematopoietic stem cell transplant (HSCT) recipients are at increased risk of malignancies, including cancers the oral cavity, with a reported observed-to-expected ratio 10.7, accounting for 14% all solid tumours following HSCT. We report 10 cases squamous carcinoma (SCC; 2016–2022) in HSCT from single tertiary centre [nine men and one woman; median age diagnosis 52 years (range 27–66)]. Thirty per cent were ex-smokers 10% current smokers. Prior to HSCT, 50% had reduced intensity conditioning, 40% myeloablative conditioning both. Eighty sibling allografts 20% matched unrelated donors. Ninety history chronic graft-versus-host disease (GVHD), affected sites mouth (n = 6), skin eyes 5), lungs 4), kidneys 3) liver 1). Forty active severe manifestations GVHD. Treatments used GVHD included topical immunosuppression 6) extracorporeal photopheresis (ECP; n 2). Median latency SCC was 4–22). At time diagnosis, not taking immunosuppressants, being treated corticosteroids immunosuppression, patient recently ECP. Examination findings induration, ulceration, tenderness, bleeding, hyperkeratosis, speckling lymphadenopathy Fifty asymptomatic. In cases, previous biopsy showed hyperplastic or dysplastic changes. The commonest tongue 4) buccal mucosa 3). stage (TNM) presentation ranged T1N0M0 T4N2M0. Sixty T3 T4 nodal involvement. Management radical surgical resection 90% cases; received adjuvant radiotherapy chemoradiotherapy. One an on lower lip underwent using Mohs micrographic surgery. duration follow-up cohort 0.8 0.4–5.7) mortality rate. our cohort, survival 0.4–5.0) SCC-specific 30% largest UK case series, best knowledge, post-HSCT. data show long onset SCC, highlighting importance regular, surveillance by haematologists, dermatologists, specialists dentists. This is recommended irrespective severity length iatrogenic immunosuppression. Intensive indicated groups higher