Positron emission tomography (PET) scans are based on the use of positron-emitting radionuclide tracers coupled to organic molecules, such as glucose, ammonia, or water. The radionuclide tracers simultaneously emit 2 high-energy photons in opposite directions that can be simultaneously detected (referred to as coincidence detection) by a PET scanner, comprising multiple stationary detectors that encircle the area of interest.
The utility of PET scanning for the diagnosis, staging and restaging, and surveillance of malignancies varies by type of cancer. In general, PET scanning can distinguish benign from malignant masses in certain circumstances and improve the accuracy of staging by detecting additional disease not detected by other imaging modalities. Therefore, PET scanning for diagnosis and staging of malignancies can be considered medically necessary when specific criteria are met for specific cancers, as outlined in the policy statements. For follow-up after initial diagnosis and staging have been performed, there are a few situations in which PET can improve detection of recurrence, and lead to changes in management that improve the net health outcome.
All policy statements apply to both positron emission tomography (PET) scans and PET plus computed tomography (CT) scans, i.e., PET scans with or without PET/CT fusion.
For the clinical situations indicated that may be considered medically necessary, this assumes that the results of the PET scan will influence treatment decisions. If the results will not influence treatment decisions, these situations would be considered not medically necessary.
In addition to the clinical situations identified below, benefits may be allowed for indications and criteria recognized in the National Comprehensive Cancer Network Guidelines (NCCN Guidelines) that is supported by NCCN 1 or 2A recommended use.
PET scanning may be considered medically necessary in the staging or restaging of muscle-invasive bladder cancer when CT or magnetic resonance imaging are not indicated or remained inconclusive on distant metastasis.
PET scanning is considered investigational for bladder tumors that have not invaded the muscle (stage <cT2).
PET scanning may be considered medically necessary in the staging or restaging of Ewing sarcoma and osteosarcoma.
PET scanning is considered investigational in the staging of chondrosarcoma.
PET scanning may be considered medically necessary in the staging or restaging of brain cancer.
PET scanning may be considered medically necessary in the staging or restaging of breast cancer for the following application:
PET scanning is considered investigational in the evaluation of breast cancer for all other applications, including but not limited to the following:
PET scanning may be considered medically necessary in the initial staging of patients with locally advanced cervical cancer.
PET scanning may be considered medically necessary in the evaluation of known or suspected recurrence.
PET scanning may be considered medically necessary as a technique for
PET scanning is considered investigational as:
PET scanning is considered medically necessary in the:
PET scanning may be considered medically necessary in the
PET scanning is considered investigational in other aspects of the evaluation of esophageal cancer, including but not limited to the following applications:
PET scanning may be considered medically necessary in the:
Head and Neck Cancer
PET scanning may be considered medically necessary in the evaluation of head and neck cancer in the
PET scanning may be considered medically necessary for any of the following applications:
PET scanning may be considered medically necessary in staging of small-cell lung cancer if limited stage is suspected based on standard imaging.
PET scanning is considered investigational in staging of small-cell lung cancer if extensive stage is established and in all other aspects of managing small-cell lung cancer.
Lymphoma, Including Hodgkin Disease
PET scanning may be considered medically necessary as a technique for staging lymphoma either during initial staging or for restaging at follow-up.
PET scanning may be considered medically necessary as a technique for assessing extranodal spread of malignant melanoma at initial staging or at restaging during follow-up treatment for advanced disease (stage III or IV).
PET scanning is considered investigational in managing stage 0, I, or II melanoma.
PET scanning is considered investigational as a technique to detect regional lymph node metastases in patients with clinically localized melanoma who are candidates to undergo sentinel node biopsy.
PET scanning may be considered medically necessary in the staging or restaging of multiple myeloma, particularly if the skeletal survey is negative.
PET scanning with gallium 68 may be considered medically necessary as a technique for staging neuroendocrine tumors either during initial staging or for restaging at follow-up.
PET scanning with other radiotracers is considered investigational in all aspects of managing neuroendocrine tumors.
PET scanning may be considered medically necessary in the evaluation of patients with signs and/or symptoms of suspected ovarian cancer recurrence (restaging) when standard imaging, including CT scan, is inconclusive.
PET scanning is considered investigational in the initial evaluation of known or suspected ovarian cancer in all situations.
PET scanning may be considered medically necessary in the initial diagnosis and staging of pancreatic cancer when other imaging and biopsy are inconclusive.
PET scanning is considered investigational as a technique to evaluate other aspects of pancreatic cancer.
PET scanning is considered investigational in all aspects of managing penile cancer.
PET scanning with carbon 11 choline or fluorine 18 fluciclovine may be medically necessary for evaluating suspected or biochemically recurrent prostate cancer after primary treatment to detect small volume disease in soft tissues.
PET scanning with gallium 68 is considered investigational in all aspects of managing prostate cancer.
PET scanning for all other indications in known or suspected prostate cancer is considered investigational.
Renal Cell Carcinoma
PET scanning is considered investigational in all aspects of managing renal cancer.
Soft Tissue Sarcoma
PET scanning is considered investigational in evaluation of soft tissue sarcoma, including but not limited to the following applications:
PET scanning is considered medically necessary for evaluating response to imatinib and other treatments for gastrointestinal stromal tumors.
PET scanning may be considered medically necessary in evaluation of residual mass following chemotherapy of stage IIB and III seminomas. (The scan should be completed no sooner than 6 weeks after chemotherapy.)
Except as noted above for seminoma, PET scanning is considered investigational in evaluation of testicular cancer, including but not limited to the following applications:
PET scanning may be considered medically necessary in the restaging of patients with differentiated thyroid cancer when thyroglobulin levels are elevated and whole-body iodine-131 imaging is negative.
PET scanning is considered investigational in the evaluation of known or suspected differentiated or poorly differentiated thyroid cancer in all other situations.
Cancer of Unknown Primary
PET scanning may be considered medically necessary in patients with a cancer of unknown primary who meet ALL of the following criteria:
PET scanning is considered investigational for other indications in patients with a cancer of unknown primary, including, but not limited to the following:
PET scanning is considered investigational when used as a surveillance tool for patients with cancer or with a history of cancer. A scan is considered surveillance if performed more than 6 months after completion of cancer therapy (12 months for lymphoma) in patients without objective signs or symptoms suggestive of cancer recurrence (see Policy Guidelines section).
As with any imaging technique, the medical necessity of positron emission tomography (PET) scanning depends in part on what imaging techniques are used before or after the PET scanning. Due to its expense, PET scanning is typically considered after other techniques, such as computed tomography (CT), magnetic resonance imaging (MRI), or ultrasonography, provide inconclusive or discordant results. In patients with melanoma or lymphoma, PET scanning may be considered an initial imaging technique. If so, the medical necessity of subsequent imaging during the same diagnostic evaluation is unclear. Thus, PET should be considered for the medically necessary indications above only when standard imaging (eg, CT, MRI) is inconclusive or not indicated.
Individual selection criteria for PET scanning also may be complex. For example, it may be difficult to determine from claims data whether a PET scan in a patient with malignant melanoma is being done primarily to evaluate extranodal disease or regional lymph nodes. Similarly, it may be difficult to determine whether a PET scan in a patient with colorectal cancer is being performed to detect hepatic disease or evaluate local recurrence. Due to the complicated hierarchy of imaging options in patients with malignancy and complex patient selection criteria, a possible implementation strategy for this policy is its use for retrospective review, possibly focusing on cases with multiple imaging tests, including PET scans.
Use of PET scanning for surveillance as described in the policy statement and policy rationale refers to the use of PET to detect disease in asymptomatic patients at various intervals. This is not the same as the use of PET for detecting recurrent disease in symptomatic patients; these applications of PET are considered within tumor-specific categories in the policy statements.
A PET scan involves 3 separate activities: (1) manufacture of the radiopharmaceutical, which may be on site or at a regional center with delivery to the institution performing PET; (2) actual performance of the PET scanner; and (3) interpretation of the results. CPT and HCPCS codes are available to code for PET scans. See the Codes table for details.
When the radiopharmaceutical is provided by an outside distribution center, there may be an additional separatecharge,or this charge may be passed through and included in the hospital bill. In addition, an extra transportation charge will be likely for radiopharmaceuticals that are not manufactured on site.
The Centers for Medicare & Medicaid Servicesadded 2 new modifiers in 2009 to facilitate the changes in the Medicare national coverage policy for PET. The modifiers are:
PI - Positron emission tomography (PET) or PET/computed tomography (CT) to inform the initial treatment strategy of tumors that are biopsy proven or strongly suspected of being cancerous based onother diagnostic testing, 1 per cancer diagnosis
PS - Positron emission tomography (PET) or PET/computed tomography (CT) to inform the subsequent treatment strategy of cancerous tumors when the beneficiary's treating physician determines that the PET study is needed to inform subsequent anti-tumor strategy.
Internal Medical Policy Committee 5-19-2020 adding wording re: NCCN indications; revised statement under Prostate cancer from "and" to "or" for clarification
Current medical policy is to be used in determining a Member's contract benefits on the date that services are rendered. Contract language, including definitions and specific inclusions/exclusions, as well as state and federal law, must be considered in determining eligibility for coverage. Members must consult their applicable benefit plans or contact a Member Services representative for specific coverage information. Likewise, medical policy, which addresses the issue(s) in any specific case, should be considered before utilizing medical opinion in adjudication. Medical technology is constantly evolving and the Company reserves the right to review and update medical policy periodically.