Survey of patient dosimetry for head and neck cancer patients undergoing external radiotherapy treatment: A study from northeastern hospitals of India

Aim : To study dosimetry of patients during the external radiotherapy of head and neck cancers from different hospitals of the northeastern region (NER) of India.
Materials and Methods : 35 confirmed cases of head and neck cancers reporting to three different hospitals in the NER of India who underwent radiation treatment were the materials for the study. Dosimetry was carried out at 8(eight) anatomical points to these patients, namely, target (entrance and exit points), forehead, chest, abdomen, gonad, arm, and leg respectively by thermoluminescence (TL) as well as optically stimulated luminescence (OSL) dosimeters. Unlike conventional appliances, we used common iodized salt as TL/OSL phosphor.
Results : Patient dosimetry was found to vary with an average of 1.17 ± 0.39 Sv at forehead, 1.24 ± 0.39 Sv at chest, 0.52 ± 0.13 Sv at gonad to a minimum of 0.26 ± 0.07 Sv at leg areas when exposed to a cumulative dose of 65 Sv at the target.
Conclusion : Maximum dose received from a stray radiation is about 1.5 Sv at forehead/chest and dosimetry of patient among the three centers is not significantly different at the 5% level of probability.

Keywords
Dosimetry, iodized salt, thermoluminescence/optically stimulated luminescence dosimeter