Identification of oral risk factors for chronic graft versus host disease in haematological patients who underwent allogeneic haematopoietic stem cell transplantation.

Objective: The aim of this prospective observational study was to identify local risk factors for the development of clinical manifestations of oral chronic Graft versus Host Disease (cGvHD) in a cohort of patients affected by haematological malignant diseases who underwent allogeneic haematopoietic stem cell transplantation (HSCT).

Materials and methods: In the context of an active collaboration between the Rome Transplant Network of the Hematology and the Oral Pathology Division at "Policlinico Tor Vergata", in Rome, 47 haematological patients were included in this trial based on a systematic dental screening and follow-up protocol. The dental checks were planned 1 month before the transplant procedure while the subsequent follow ups were scheduled on day +100, +180, +365 and + 730 after the transplant. The tool used for the dental checks was a detailed report including all the potential oral features responsible of mechanical, chemical or infective injuries, except for the drugs.

Results: Overall, 64% of patients (N=30) did not perform dental hygiene during the screening pre-transplant and 53% (25/47) developed cGvHD with oral involvement. The most part of patients (84%) who experienced oral manifestations of cGvHD during the follow-up period after HSCT did not perform dental hygiene before the transplant procedure. Moreover, the comparison between the "presence" or "absence" of dental hygiene before the allogeneic HSCT showed a statistical significant increasing during the follow-up period in the occurrence of oral lesions due to the cGvHD for patients who lack pre-transplant dental care (p=0.029).On the contrary, the frequency of the other factors such as malocclusions, fractured teeth, incongruous prosthesis, food, smoke, alcol and bad habits, resulted similar between the group with or without typical oral lesions of cGvHD.

Conclusions: The prevention of oral infectious complications provided by primary and secondary dental cares can result in a great benefit for haematological patients who underwent allogeneic HSCT. The combined hematological and dental management represents a clinical need before and after allogeneic HSCT for the removal of inconvenient issues with impact on the short and long-term outcome. Poor dental hygiene seems to be a local risk factor for the development of oral lesions due to cGvHD. However, a larger cohort of patients is necessary to confirm these preliminary data and to evaluate the best preventive and therapeutic oral hygiene protocol in this specific setting.