الفهرس 
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Abstract
Mycosis fungoides is the most common type of cutaneous lymphoma, it’s about 50% of all lymphomas arising in the skin, approximately 75% of primary cutaneous lymphomas are T-cell driven, two thirds of which may be classified into mycosis fungoides, which is generally indolent in behavior and sézary syndrome, an aggressive and leukemic variant. Total skin electron irradiation (TSEI) is a long-established treatment technique known since almost a century. In cases of primary cutaneous T-cell lymphoma, including mycosis fungoides, TSEI is a very effective single modality treatment as it is suitable to deliver a uniform dose to the entire skin surface to cure the superficial pruritic patches and plaques, and therefore, it achieves therapeutic dose levels to the skin and a rapid fall-off in the tissue underneath. Total skin irradiation is challenging. Different treatment approaches have been studied over the past years: (1) large electron field techniques, (2) rotational techniques, and (3) techniques involving patient’s shift during irradiation. In the case of large electron field techniques, the patient is treated with irradiation while standing.
The purpose of this study:
The study’s objective was to evaluate the radiation dose distribution at different body sites for mycosis fungoides patients treated by total skin electron irradiation.
Study Preparation and Description:
The present study included ten (six males and four females) mycosis fungoides (total skin) cancer cases received radiotherapy treatment (every one of them received 36 Gy over 36 fraction (1 Gy per fraction) scheduled as 4 fractions per week (Saturdays, Sundays, Tuesdays,
Wednesdays)) using Total Skin Electron Irradiation modality using Stanford TSEI technique with electron energy of 6 MeV, in order to evaluate the radiation dose distribution at different body sites. All treatment fields were delivered at collimator angle 0˚, using electron applicator of 25x25cm2 size and at SSD of 4 meters from the patient body surface. Eighteen TLD chips were used to measure the dose distribution at eighteen different points on the skin of the whole body for every patient under the study. The all TLDs readings were collected and analyzed in order to evaluate the dose distribution homogeneity over the different positions on the body surface.
The results of this study showed the following:
For female patients included in this study, TLDs under the breast fold (TLD no.15) has received the least dose among all TLDs sites, that is because of being them lying under the breast fold. TLD no.17 has received lower mean dose (83.9 ± 1.98 cGy) because of being it located at a hidden position (above the shoulder) from the beam angle direction specially in the tall patients (from 170-180 cm). TLD no. 18 (under arm) has received lower dose because of being it is almost covered with a part of the humerus which prevents some amounts of radiation from being delivered to it. TLDs no. 4 (inner side of forearm) and no. 11 (outer side of forearm) have received lower doses in some cases relative to other sites on the skin surface. The points lying near the beam center (i.e. TLDs no. 2 (lt ant. Chest), 5 (below the navel) and 9(rt upper back)) have received higher doses than those lying on the peripheral points (i.e. TLDs no. 3 (lt inner humerus) and 10 (rt outer humerus)).