This is an observational study. This protocol will determine the feasibility of using a novel nano-material based fiber-optic dosimeter (nanoFOD) device, with dimensions less than 1 mm wide, to measure real-time, pin-point, in-vivo radiation dose given during external beam delivery of radiation therapy treatments.This new protocol is similiar in design to Pro00050297 with the significant difference being the monitoring will be performed during external baem radiotherapy.

The device is currently in use in an ongoing IRB approved protocol Pro00050297 "Real Time In-Vivo Dosimetry For Gynecologic Brachytherapy". Brachytherapy is an integral part of the management of many gynecological cancers, which uses radioactive isotopes to deliver radiation treatment in close proximity to the target. The protocol uses the device in the setting of gynecologic brachytherapy to monitor real time doses, with a primary endpoint of feasibility and accuracy. Accrual is ongoing, however, the device has initially given consistent results, within 3% of the expected values. This initial experience is intentionally designed with the simplest geometry and positioning. This protocol has a similar design to the initial brachytherapy trial, but with the significant difference that the monitoring will be performed during external beam radiotherapy. Calibration procedures are different in this scenario, and the considerations of when and where dose monitoring will be useful are distinct from these considerations in brachytherapy.

Inclusion Criteria:

• Histologically documented neoplasm of the pelvis (including gynecologic, gastrointestinal, and genitourinary origin).
• Planned external beam radiotherapy as part of standard of care treatment
• The radiotherapy plan involves the body surface
• Age > 18 years
• Able to provide and execute informed consent

Exclusion Criteria:

• Allergy or previous intolerance of skin adhesives
• Any clinical scenario in which the nanoFOD placement or reading would compromise the treatment efficacy, or endanger the patient in any way.

Subjects with histologically documented neoplasm of the pelvis (including gynecologic, gastrointestinal, and genitourinary origin).