A dose volume histogram in integral form for PTV provides which information?

The dose volume histogram (DVH) in integral form for the planning target volume (PTV) specifically provides the percentage of the PTV that receives at least the prescribed tumor dose. This is critical information in radiation therapy as it allows clinicians to evaluate how effectively the treatment plan covers the target volume while adhering to dose constraints. By assessing this percentage, dosimetrists and radiation oncologists can confirm that the majority of the PTV is adequately dosed to achieve effective tumor control.

This aspect of the DVH is particularly important because ensuring sufficient dose delivery to the tumor is essential for treatment efficacy. A proper understanding of how much of the PTV receives at least the prescribed dose can influence treatment decisions and adjustments, thereby impacting patient outcomes. Thus, option C aligns directly with the fundamental purpose of the DVH in evaluating dose distribution within the target area.