The retrospective study analysed treatment records since 1997 for patients receiving definitive radiation therapy - with or without surgery and chemotherapy - for squamous-cell carcinomas of the throat, including oropharynx, hypoharynx and larynx. Definitive radiotherapy is a curative course of radiation treatment designed to eradicate a known cancer.

Eligible patients - a total of 90 - had either stage III or IV cancer with no prior surgery or radiation therapy in the head and neck region and remained cancer-free 18 months or more after completing radiation therapy. Sixty percent had two-dimensional treatment planning for radiation therapy while 40 percent had three-dimensional CT-based treatment planning.

A feeding tube was placed in 56 of these 90 patients (62 percent): 19 before radiation therapy; 26 during radiation therapy; and 11 after radiation therapy. Two-thirds of the men had the feeding tube removed during the follow-up period, with only 15 percent retaining the tube after 18 months.

"In analysing the factors associated with feeding tube dependency at 18 months, only the higher T stage and 2-D treatment planning were independent predictors," said medical intern Linna Li, M.D from Fox Chase Cancer Center. "Of the 54 patients who had 2-D treatment planning, 20 were feeding-tube dependent at 18 months compared to just five of the 36 who had 3-D treatment planning. Of the three patients who had intensity-modulated radiation therapy instead of conventional radiation, none were feeding-tube dependent.

"Three-dimensional treatment planning can help patients avoid feeding tube dependency," Li concluded. "Possible explanations may be improved tumour targeting with smaller areas receiving high doses or more evenly distributed doses in large radiation fields."; Source: Fox Chase Cancer Center