Radiation-induced Sarcoma in the Head and Neck: Clinical, Imaging, Histopathological, and Therapeutic Characterization

Abstract

Radiation-induced head and neck sarcoma (RIHNS) is a rare and serious long-term complication of radiotherapy (RT), with poor prognosis and high morbidity and mortality. Diagnosis is based on immunohistochemistry and molecular biomarker analysis, and therapy is usually surgical. Other adjuvant therapies might be considered. This case report aimed to describe the clinical, imaging, histopathological, and therapeutic characteristics of a rare case of RIHNS in the mandible after 21 years of RT. A 68-year-old male patient underwent a partial left parotidectomy in 1995, was diagnosed with pleomorphic adenoma, and after recurrence of the lesion in 2000, underwent an ipsilateral total parotidectomy with adjuvant RT. In May 2021, he complained of an ulcerated nodular lesion on the tongue that extended toward the lower gingiva, associated with oral bleeding and difficulties with swallowing. After biopsy in the gingival margin and histopathological analysis, the diagnosis of high-grade spindle-cell sarcoma was established. Complete surgical resection with microsurgical reconstruction using a fibular osteomusculocutaneous free flap was performed. RIHNS could appear after a period of almost 20 years after RT. Surgical resection with reconstructive surgery was a reliable and feasible therapeutic option that showed favorable clinical results after an appropriate follow-up.

Fig. 1.

Presurgical imaging analysis. MRI-axial section showed lower and higher signals on T1 and T2, respectively, with intense contrast enhancement, approximately 3.5 × 3.5 × 2.0 cm that extended laterally toward the left mandibular angle.

Fig. 2.

Reconstructive microsurgery with fibular free flap. Reconstructive titanium plate placed and fixed in the anterior arch and remnant left hemimandible. Microsurgical reconstruction with fibular osteomusculocutaneous free flap.

Fig. 3.

Histopathological assessment and IHC analysis. After H&E, at 400× magnification, exacerbated nuclear atypia, including marked pleomorphism, heterogeneous chromatin distribution, and multiple nucleoli, was visualized.

Fig. 4.

Reirradiation protocol using stereotactic body radiation therapy technique after reconstructive surgery. Color wash of RT planning dose distribution in the axial.