Radiobiology and radiation treatment of malignant melanoma: A review

Abstract

AbstractThe incidence of malignant melanoma (MM) has one of the fastest growth rates in the world and external beam radiation therapy (RT) is an important component in the total therapeutic management of MM. The radiobiology of MM provides a fascinating example of the complexities of radiation tumor biology. Both the multitarget model and the linear quadratic model predict that high dose per fraction (HDPF: 400 cGy or more) RT may be more efficacious than low dose per fraction (LDPF: 180–300 cGy) RT for some MM. However, other radiobiological factors such as repair of potentially lethal damage, reoxygenation, and repopulation appear to support the use of LDPF RT. Therefore, the MM radiobiological data predict a diverse response to a wide spectrum of HDPF and LDPF time‐dose prescriptions. The clinical data for MM are consistent with these radiobiological predictions. MM exhibits a high response rate to both HDPF and LDPF time‐dose prescriptions. RT is an effective therapy for MM in many clinical settings: 1) RT is the single most effective local therapy for metastatic disease with complete response rates of 23–72% and long‐term local tumor control rates of 48–82%; 2) heavy ion RT is the primary treatment for many ocular MM with 5‐year eye retention rates of 89% and 5‐year local tumor control rates of 96%; 3) RT is the treatment of choice for mucosal non‐cutaneous, non‐ocular MM with results that are equal or superior to radical surgery; and 4) recent reports suggest an important role for adjuvant RT in postoperative patients who are at high risk for local‐regional recurrence. The current roles for RT in MM should be reevaluated since it is likely that RT is being underutilized in the overall clinical management of MM. © 1994 Wiley‐Liss, Inc.