Allogeneic haematopoietic stem cell transplantation in myelodysplastic syndromes

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.

Post-Transplantation Natural Killer Cell Count: A Predictor of Acute Graft-Versus-Host Disease and Survival Outcomes After Allogeneic Hematopoietic Stem Cell Transplantation

BACKGROUND

Reconstitution of the immune system after allogeneic hematopoietic stem cell transplantation (allo-HSCT) plays an important role in post-transplant outcomes. However, the clinical relevance of the lymphocyte subset (LST) counts to transplant-related complications and survival outcomes after allo-HSCT has not been fully elucidated.

PATIENTS AND METHODS

A total of 70 patients who had undergone allo-HSCT from 2007 to 2013, with LST results both 7 days before conditioning and 30 or 90 days after allo-HSCT were included. The LST counts in the peripheral blood were determined using 6-color flow cytometry. Clinical information, including transplant-related events during the first 100 days after allo-HSCT, was reviewed, and any association between these events and LST was analyzed.

RESULTS

At 30 days after allo-HSCT, the CD4⁺ T-cell (P = .009) and B-cell (P = .035) counts were lower and the natural killer (NK) cell count was greater (P < .001) than before conditioning. The CD8⁺ T-cell (P = .001) and NK cell (P < .001) counts were high 90 days after transplantation. The hazard ratios for a low NK cell count on days 30 and 90 for acute graft-versus-host disease were 6.22 and 14.67, respectively. Patients with low NK cell counts at 30 and 90 days after allo-HSCT had poorer overall survival (P = .043 and P = .028, respectively) and greater nonrelapse mortality (P = .036 and P = .033, respectively). A low NK cell count on day 30 was still prognostic for overall survival (P = .039) on multivariable analysis.

CONCLUSION

NK cell counts after allo-HSCT, especially on day 30, were predictive of acute graft-versus-host disease, nonrelapse mortality, and survival. Serial lymphocyte subset analysis can be used to identify and treat patients at risk during the early period after allo-HSCT.