Acute promyelocytic leukaemia presenting with gingival hypertrophy: an atypical oral presentation

Acute promyelocytic leukaemia (APL) is a subtype of acute myeloid leukaemia characterised by the PML–RARα fusion gene and a high risk of early mortality if treatment is delayed. Gingival hypertrophy is an uncommon manifestation of APL and is more typically associated with monocytic and myelomonocytic AML. We report a 26-year-old male who presented with a three-week history of progressive gingival enlargement, initially managed as gingivitis for two weeks, resulting in delayed haematological evaluation. Microgranular APL was confirmed by bone marrow morphology and fluorescence in situ hybridisation, demonstrating t(15;17). Although pancytopenia was present, the absence of hyperleukocytosis or overt coagulopathy contributed to an atypical clinical picture. Due to resource constraints, all-trans retinoic acid–based therapy was unavailable, and induction chemotherapy was administered, with a fatal outcome after one week. This case highlights gingival hypertrophy as an atypical early presentation and the impact of delayed diagnosis and limited access to essential therapy.