Oncology Coding Article – CPT code 77336

Specialty Groups — Oncology

Coding a Physics Week

There is ongoing controversy over the date of service to use when billing weekly physics consultation (CPT code 77336). While the bottom line is always follow individual payor guidelines, there is some authoritative guidance for the date of service assigned to weekly physics. First, it is important to remember that the actual descriptor of this code in the CPT Manual is “Continuing medical physics consultation, including assessment of treatment parameters, quality assurance of dose delivery, and review of patient treatment documentation in support of the radiation oncologist, reported per week of therapy.”

While some radiation oncology coders and technical staff think of this service as constituting the weekly physics chart review, this is only part of the ongoing services provided by the medical radiation physicist. It is true that the chart review provides tangible evidence of this consultative relationship, and ensures the documentation that coders and auditors point to when justifying the charge for physics services. The Fall 1991 CPT Assistant provides additional information on CPT code 77336: “This code includes the overall quality control, machine calibration, film badge service, and a host of other physics related procedures that assure the radiation oncologist that the quality control functions have been appropriately carried out. These activities are also beneficial to each patient undergoing radiation treatment. This is generally reported on a weekly basis.”

Both the descriptor of the code (“reported per week of therapy”) and the documentation in the CPT Assistant (“reported on a weekly basis”) indicate that this service is reported once per week of radiation therapy. In the world of radiation therapy, however, a week is not the traditional seven (7) days, but instead constitutes five (5) therapy treatments, regardless of the period of time required to deliver these five fractions. As a result, the radiation “week” may constitute a period of time that varies from 2.5 days for BID therapy (hyperfractions) to an extended period of time when the patient has a break in therapy.

Many Medicare Local Medical Review Policies (LMRPs), including carriers and fiscal intermediaries for North Carolina, Colorado, North Dakota, South Dakota, Wyoming, and Maine include the following statement in their policy: “This procedure [continuing physics, 77336] is reported weekly (once every consecutive five treatments delivered), a frequency that would match the weekly radiation treatments billed.” While most payors require that continuing physics services be billed at the 5th fraction, 10th fraction, etc., there must be documentation supporting the chart review within each 5-fraction segment.

The method of documentation varies from one facility to another, and while there is no one way to record this service, payors may require a physics chart check document that is specific to the individual patient and maintained as part of the radiation oncology medical record. The initials of the physicist on the treatment record may be the accepted documentation in some facilities, but auditors do not always accept these initials as evidence of a chart review based on the definition of the CPT code, supporting CPT Assistant guidance and the ACR standard of practice documentation. According to the American College of Radiology, “The qualified medical physicist shall develop a chart check protocol for reviewing treatment delivery. This protocol should review new or modified treatment fields, treatment prescription, simulation instructions, isodose distributions, special dose calculations and measurements, daily monitor units (time) calculations, in vivo measurements, daily treatment records, physics chart review, and cumulative doses. If record-and-verify systems are used, then the physics chart check protocol shall include reviewing the treatment setup and dose parameters to ensure treatment prescription adherence.”

Weekly Physics Review (example)

Patient Name:

Treatment Start Date:


[Week 1]

[Week 2]

[Week 3]

[Week 4]

[Week 5]

[Week 6]

[Week 7]

[Week 8]


# of Fractions



Computer Plan

MU Calcs/SSD

Ind Calc Done

Dose Sums

Tx Programmed

Treatment Aids

Previous Tx


Special Doses

Setup Info




Physics Initials