卡氏肉瘤是一種原發性多處皮膚色素沈著且血管豐富的肉瘤，卡氏肉瘤在顯微鏡下主要由紡錘狀細胞（spindle-shaped cells）所組成的血管腔，根據其皮膚潰瘍形態、組織學及地域、發病人種等不同的臨床症狀，大致可分為四種類型，即典型卡氏肉瘤、地域型卡氏肉瘤、免疫抑制型卡氏肉瘤、流行性卡氏肉瘤。本研究實際用於卡氏肉瘤病患小區域單一病灶治療時，在治療過程輔以電子錐筒限制照野範圍，以5×5 cm2的電子錐筒加鉛擋塊（insert block）成3×3 cm2做治療。由電腦化水假體系統量測出5MeV，3×3 cm2與15×15 cm2電子錐筒的最大劑量深度分別為0.97 cm與1.07cm，本研究以15 cm2×15 cm2的電子錐筒輸出劑量為治療儀器校正標準值，則治療時所使用3×3 cm2的電子錐筒因數（cone factor）為0.555，故病患於每日治療計劃中需給予3Gy 的劑量，其換算後的監測單位為541 MU（monitor unit）。

Kaposi’s sarcoma (KS) is a neoplastic disease of the vascular endothelial cells. KS shows a vascular cavity full of spindle-shaped cells under microscope observation. Based on severity of skin ulcer, different histology, various living region and diverse human species, there are four variants of KS including the classic, endemic, immunosupression and epidemic forms. This study is aimed to evaluate the radiotherapy of single lesion KS by electron beam. We use a 5×5 cm2 electron cone coupled with
insert block to form a 3×3 cm2 therapeutic field. The maximum depth of 3×3 cm2 and 15×15 cm2 evaluated by Scanditronic water phantom and Scanditronic dosimeter are 0.97 cm and 1.07 cm, respectively. The calibrated parameter of 3×3 cm2 electron cone, using 15×15 cm2 as calibration standard in the study, is 0.555. Thereby, the calculated radiotherapeutic dose is 541 MU (monitor unit) when we use 3 Gy as daily therapeutic dose.