Case of papillary thyroid cancer presenting with an inoperable cervical mass successfully treated with high-dose radiation therapy

Abstract

External-beam radiation therapy (EBRT) for differentiated thyroid cancer has been controversial. Palliative irradiation is usually recommended for patients with treatment-resistant relapse and/or distant metastases, but high-dose EBRT is not often indicated in this situation. A 50-year-old man had treatment-resistant recurrence of an inoperable cervical mass and multiple lung metastases after total thyroidectomy and neck dissection. Because the patient had good performance status and no other life-threatening metastases, he received high-dose intensity-modulated radiation therapy (IMRT). Remarkably, the tumour shrank during treatment. After 3 months, he had bleeding from the internal carotid artery. The bleeding was outside the high-dose irradiation site and was likely due to infection; emergency interventional radiology was performed. The post-EBRT clinical course was favourable and the cervical mass almost disappeared. The patient remained alive for 3 years post treatment. It is possible to extend the indication of high-dose intensity-IMRT in selected patients with differentiated thyroid cancer.

Keywords: head and neck cancer; radiotherapy.

Figure 1

Pretreatment images: body-surface image (A) and enhanced CT scan in coronal plane (B). Images 1 year after treatment: body-surface image (C) and enhanced CT scan in coronal plane (D).

Figure 2

Dose distribution of intensity-modulated radiation therapy in coronal plane (A) and axial views at laryngeal (B). (C) Dose volume histogram depicting the dosimetric parameters analysed at the central gross tumour volume (pink), marginal planning target volume (red), left carotid artery (green), trachea (yellow), spinal cord (blue) and lungs (light blue).