Follow-up and Adverse Effects—The mean (SD) follow-up time was 47.16 (15.78) months. The patients were free of symptoms, and there were no adverse effects derived from the treatment during follow-up.
Comment
The primary goal of OLP treatment is to stop the outbreaks.1,9,13 The lack of potency of corticosteroids in some patients with OLP could be due in part to the inadequate selection of the vehicle (ointment/oral rinse) for the extension and characteristics of the lesion or because of an inappropriate prescription dose, time, and/or frequency, as described by González-Moles.17 However, even when using an appropriate protocol, some lesions are resistant to topical treatment and require other therapeutic modalities.1,9,13 Previously proposed topical treatments include different immunosuppressants, such as the mammalian target of rapamycin, tacrolimus ointment 0.1%, pimecrolimus cream 1%, or cyclosporine A (50–100 mg/mL) formulations.18 Nevertheless, these drugs seem to have a greater number of side effects than topical steroids, and tacrolimus has been associated with cases of oral malignancy after continuing treatment.15
Severe and/or recalcitrant lesions and extraoral involvement have been successfully treated with systemic prednisone (40–80 mg/d).1,9,13 Nevertheless, systemic corticosteroid toxicity requires that these treatments should be used only when necessary at the lowest possible dose and for the shortest possible duration.19 Other nonpharmacologic options for treatment are photodynamic, UV, and low-level laser therapy.20,21 They have been accepted as supplementary modalities in different inflammatory skin conditions but present important technical requirements. Their effectiveness in corticosteroid-resistant cases have not been definitively assessed. Interestingly, promising results recently have been reported by Bennardo et al22 when comparing the efficacy of autologous platelet concentrates with triamcinolone injection.
In our study, the use of PRGF stopped the lesions’ evolution since the first treatment session, reducing them by 6.5-fold. The positive effects observed may have been promoted by the activity of different proteins present in PRGF (eg, platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor, epidermal growth factor, fibroblast growth factor, fibronectin). These molecules contribute to collagen synthesis; angiogenesis; endothelial cell migration and proliferation; or keratinocyte cell migration, proliferation, differentiation, growth, and migration—phenomena that are essential for healing and re-epithelialization.23-25
Different studies also have supported an anti-inflammatory effect of PRGF mediated by an inhibition of the transcription of nuclear factor–κB and the expression of cyclooxygenase-2 and chemokine receptor type 4 produced by its high content of hepatocyte growth factor or the reduction of inflammatory marker expression, such as intercellular adhesion molecule 1. The development of an efficient 3-dimensional fibrin scaffold formation that occurs after PRGF administration also could facilitate healing, helping some cell populations to guide their position and function.23-25
Limitations of our study include the small number of patients and the absence of a control group. The higher number of female patients in the study did not seem to affect the results, as differences related to gender have not been reported when treating patients with OLP with autologous platelet concentrates or other modalities of treatment.
Conclusion
Results from our study indicate that the use of PRGF could be a new treatment option for OLP cases refractory to conventional therapy. No complications were observed during the treatment procedure or during the complete follow-up period. Nonetheless, new prospective studies with a greater number of patients and longer follow-up periods are needed to confirm these preliminary results.