Sarcoma of the cervical spine after radiation treatment for thyroid cancer

Radiotherapy-induced tumors of the spine, peripheral nerve, and spinal cord: Case report and literature review

BACKGROUND

The development of a secondary malignancy in the field of radiation is a rare but well-recognized hazard of cancer treatment. The radiotherapy-induced (RT-I) tumors are even more aggressive and potentially lethal than the primary tumor. To goal of this article is to report a case of RT-I neural tumor located in the peripheral nerve and spinal cord and to perform a literature review of the subject.

CASE REPORTS

Thirty-year male with symptoms of hypoesthesia and dysesthesia of the L5 nerve root distribution and previous treatment of a testicular seminoma 20 years previously. The lumbar magnetic resonance imaging showed the growth of a nerve root tumor. Surgery was performed, and a fusiform tumor was resected with clear margins. The anatomopathological and immunohistochemical studies were compatible with a malignant peripheral nerve sheath tumor. A total of 30 cases were included in the review. The mean age of the patients at diagnosis of the induced tumor was 39.36 (±16.74) years. Most were male (63.3%). The main type of primary disease was neural tumors (30%). The most common type of histology was fibrosarcoma (20.0%). No difference was found in age, gender, and time of diagnosis between neural and nonneural tumors. The mean survival after the diagnosis of the secondary tumor was 10.7 months (±13.27), and neural tumors had a longer survival period (P = 0.031).

CONCLUSION

The current gold standard therapy is complete resection with clear margins, since most tumors do not respond to chemotherapy and RT. The neural type of RT-I tumor presented a longer survival period.

Radiation-Associated Low-Grade Extraskeletal Osteosarcoma of the Neck Following Treatment for Thyroid Cancer

Low-grade extraskeletal osteosarcoma is a rare tumor that may arise de novo or following radiation therapy. Because of the low-grade histology, it may be misdiagnosed as a benign lesion. We present a case of a 59-year-old man with a past history of radiotherapy for papillary carcinoma of the thyroid, presenting 16 years later with a low-grade extraskeletal osteosarcoma of the neck. The patient was treated with surgical excision and is disease free after 12 months of follow-up. The prognosis for patients with low-grade extraskeletal osteosarcoma is relatively good when compared with high-grade sarcomas. While there is a report of a low-grade extraskeletal osteosarcoma arising following radiotherapy for a benign condition, to the best of our knowledge this is the first reported case of a low-grade extraskeletal osteosarcoma occurring following radiotherapy for thyroid cancer, and the only case reported in the soft tissue of the head and neck region.