The PLUNC 3D treatment planning system: a dynamic alternative to commercially available systems.

Three-dimensional (3D) treatment planning is an integral step in the treatment of various cancers when radiation is prescribed as either the primary or adjunctive modality, especially when the gross tumor volume lies in a difficult to reach area or is proximal to critical bodily structures. Today, 3D systems have made it possible to more precisely localize tumors in order to treat a higher ratio of cancer cells to normal tissue. Over the past 15 years, these systems have evolved into complex tools that utilize powerful computational algorithms that offer diverse functional capabilities, while simultaneously attempting to maintain a user-friendly quality. A major disadvantage of commercial systems is that users do not have access to the programming source code, resulting in significantly limited clinical and technological flexibility. As an alternative, in-house systems such as Plan-UNC (PLUNC) offer optimal flexibility that is vital to research institutions and important to treatment facilities. Despite this weakness, commercially available systems have become the norm because their commissioning time is significantly less and because many facilities do not have computer experts on-site.