RADIATION RESPONSE OF CLEAR CELL PAROTID CARCINOMA: A CASE REPORT

Clear cell carcinomas originate primarily from kidney. They also originate from different parts of the organs and tissues of the body. They are rarely seen in the head and neck region, especially in the parotid gland. Our case is 19 years old female. She presented with tooth pain and a fast growing mass in the right parotid gland after pregnancy. MRI showed a mass which replaced the right parotid gland and extended to right parapharyngeal region, invaded maxilla, mandibula, chewing muscles, extended to the base of the skull and obliterated the foramen ovale. Biopsy has been taken and reported as low differentiated clear cell carcinoma. The case was consulted with head and neck surgeons and accepted as unresectable and inoperable staged tumour. Physical examination showed 11x9 cm mass on the right parotid region. The tumour opened to the oral cavity and filled up right half of it. Trismus and right facial palsy were present. The patient refused neoadjuvant chemotherapy, so was treated with primary radiotherapy. Co60 teletherapy and 9MeV electron treatment units were used. With conventional fractions 66 Gy to the primary tumour, 56 Gy to the regional lymph nodes and 50 Gy to the neck were given. One month after the radiotherapy, primary tumour showed well regression, six months later complete response was achieved. However she had dyspnea at the end of 15. month and chest x-ray showed pulmonary metastases. She then received two courses of chemotherapy. Unfortunately she died with progression of pulmonary metastases at the end of the 19. month without recurrence of primary tumour.

Keywords: parotid gland, clear cell carcinoma, radiotherapy, response