Repeat Radiation for Local Recurrence of Head and Neck Tumors and in Prostate Cancer

Abstract

Background: Recent advances in diagnostic methods and in radiotherapy now increasingly enable repeat radiotherapy with curative intent for the treatment of previously irradiated lesions. In this review, we present data on oncological outcomes and on acute and late sequelae, as far as these are currently known, in patients with head and neck tumors (HNT) or prostate cancer (PCa) who underwent repeat radiotherapy after prior radiotherapy with curative intent.

Methods: This review is based on clinical series with over 20 patients that were published between May 1998 and April 2018 (HNT) or between October 1998 and October 2018 (PCa) and were retrieved by a search in the PubMed database.

Results: Most of the clinical series retrieved were retrospective and uncontrolled. There were 16 studies that included 2678 patients with recurrent head and neck tumors, and 8 that included 245 patients with recurrent prostate cancer. In patients with squamous cell carcinoma of the head and neck, intensity-modulated radio - therapy (IMRT) and stereotactic body radiotherapy (SBRT) yielded three-year survival rates of 47-57% but also produced substantial acute and late adverse effects. Most of the studies concerning recurrent PCa involved small patient groups. In these studies, repeat radiotherapy with SBRT yielded tumor control rates of 40-80% after 11-24 months of follow-up, with only mild acute toxicity.

Conclusion: Although no comparative studies are available, it seems that modern external beam radiotherapy techniques can be used for repeat radiotherapy of locally recurrent head and neck tumors with curative intent after careful patient selection. Repeat radiotherapy of PCa must still be considered experimental, but initial results from small-scale trials are encouraging. The long-term adverse effects cannot yet be accessed. Patients should be selected by an interdisciplinary tumor board. This type of treatment is generally carried out in a specialized center.

eFigure

Head and neck tumors: The search strategy yielded 197 studies. 16 studies, which included a total of 2678 patients, remained after the inclusion and exclusion criteria were applied. Among these patients, 85 were treated in two prospective trials and 2593 were treated in 14 retrospective studies. Most of the studies included recurrent or second tumors in multiple tumor sites (nasopharynx, oropharynx, hypopharynx, oral cavity, larynx, paranasal sinuses, cancer of unknown primary) as well as regional recurrences in the cervical lymph nodes. Prostate cancer: The search yielded eight studies with a total of 245 patients satisfying the above inclusion criteria. All studies but one were retrospective, single-center analyses (25). HNT, head and neck tumors; PCa, prostate cancer; re-RT, repeat radiotherapy; EBRT, external beam radiotherapy; BT, brachytherapy