A 54-year-old male patient, smoker and moderate drinker, allergic to penicillins, with a history of episodes of maxillary sinusitis and pansinusitis. He was diagnosed with a plasmacytoma of the left frontal sinus following a sinus puncture biopsy in another hospital, where it was surgically excised by means of an incision at the level of the left eyebrow and an osteotomy of the anterior wall of the sinus. A fragment of the sinus cavity was obtained for anatomopathological analysis confirming the presence of the plasmacytoma. Histopathological analysis of the excised sinus mucosa was also performed, which was reported as a possible abscessed mucocele (mucopiocele).
He was subsequently referred to the haematology department of our hospital for further treatment. Bone scintigraphy showed pathological deposition of the tracer in the maxillary sinus, nasal bones and frontal sinuses, suggesting the presence of myeloma. Three cycles of chemotherapy were administered one month apart, consisting of vincristine, adriomycin and dexamethasone + Aredia (1st cycle); cyclophosphamide, etopoxide, dexamethasone + Aredia (2nd cycle); and cyclophosphamide, adriomycin, dexamethasone + Aredia (3rd cycle). Two days after the end of the third cycle of chemotherapy treatment, an increase in tumour was observed in the frontal region, with signs of local inflammation of 24 hours of evolution. On examination, a soft tumour was palpable in the frontal region, draining abundant purulent material through two orifices located in the eyebrow, with headache and fever of 38ºC. Samples were taken for culture and antibiogram (no microorganisms were isolated). Skull X-ray showed a radiolucent area at the level of the frontal bone. CT and MRI confirmed the presence of thickening of the frontal bone and occupation of its cavities with a lytic area on the left side suggestive of osteomyelitis with areas of sequestration at frontal level.

The patient was referred to our Maxillofacial Surgery Department and after evaluation of the patient, it was decided to carry out surgical treatment. A butterfly incision was made in the glabellar region including the fistulous tract. After detaching the flap, the frontal sinus, which had lost its external table, was visualised, cleaned and curetted, and the sinus walls were reamed with rotating material. A 50 cc cortico-cancellous bone graft was taken from the right proximal tibia using a trocar, which was mixed with a previously prepared PRP growth factor-rich fraction concentrate. 250 cc of venous blood was drawn to prepare the PRP, centrifuged using a two-stage technique (Platelet Concentrate Collection System PCCS; 3i/Implant Innovations, Palm Beach Gardens, FL®), and the two fractions were separated. Prior to application, the PRP clot was activated by calcium chloride. In total, a mixture of 40 cc of material was obtained, with which both sinus cavities were completely filled. The surgical wound was sutured and plasma poor in growth factors was placed over the scar.

The curettage material from both sinus cavities was sent for pathology analysis. The result reported the presence of mixed inflammatory tissue with bone and soft tissue involvement, ruling out recurrence of plasmacytoma, and the diagnosis was chronic osteomyelitis of the frontal sinus.
The patient was discharged after five days of hospitalisation with no symptoms or postoperative complications. There were no complications at the donor site, and the patient was discharged without discomfort. CT scans were performed six and twelve months after the operation, showing complete filling of the sinus cavity, with no signs of disease. The patient had no further frontal swelling or discharge, headaches or fever. The aesthetic appearance of the surgical wound is very satisfactory....