Adenoid cystic carcinoma of trachea treated with adjuvant hypofractionated tomotherapy. Case report and literature review

Adenoid cystic carcinoma, also called cylindroma, is the second most common histological type of tracheal malignancy but represents 1% of all respiratory tract cancers. We report a case of a 59-year-old patient submitted to an incomplete resection of the trachea and subsequently treated with adjuvant tomotherapy. There have been no reports in the literature regarding intensity-modulated radiation therapy with linac or tomotherapy systems in adenoid cystic carcinoma of the trachea. The present clinical case demonstrates the feasibility of adjuvant intensity-modulated radiation therapy techniques for optimizing the dose coverage of the tumor bed while sparing surrounding normal tissues. A dosimetric comparison between the tomotherapy plan and a 3-dimensional conformal radiotherapy plan is also reported. We demonstrate that tomotherapy permits an increase in the dose per fraction without important acute adverse effects. At 24 months’ follow-up, our patient shows no evidence of disease with negative histological findings.