ICD-10 C37 is officially defined as "Malignant neoplasm of thymus." code C37 is referenced in 19 tracked payer policy changes from Blue Cross Blue Shield of North Dakota, Health Net, and 2 other payers. For billers and coders, staying current on payer-specific coverage criteria, reimbursement rules, and prior-authorization requirements for code C37 is critical to clean claim submission. Each entry below links to the full policy analysis with effective dates and action steps.
Blue Cross Blue Shield of North Dakota has updated multiple pharmacy prior authorization policies for specialty medications, with new requirements effective October 1, 2025 for Datopotamab deruxtecan-dlnk (Datroway) and revised policies for various oncology drugs effective November 1, 2025. These changes affect prior authorization criteria, step therapy requirements, and billing codes for high-cost specialty medications.
Health Net updated multiple medical policies in Q4 2020, affecting prior authorization requirements, coverage criteria, and billing codes across numerous specialties including oxygen therapy, allergy testing, bariatric surgery, wound care, and various diagnostic procedures.
Health Net updated multiple medical policies in Q4 2020, affecting prior authorization requirements, coverage criteria, and billing codes across numerous specialties including oxygen therapy, allergy testing, bariatric surgery, and wound care. Most changes involve revised medical necessity criteria and updated CPT/ICD-10 codes that require immediate attention for proper billing and authorization processes.
CalViva Health updated multiple medical policies for Q4 2020 affecting prior authorization requirements, coverage criteria, and billing codes across numerous specialties. Key changes include revised oxygen therapy criteria, new ambulatory surgery center redirection requirements, updated bariatric surgery protocols, and modified coverage for various diagnostic and therapeutic services.
Commercial prior authorization medical drug policies have revisions effective March 17, 2026, with many policies adding the Appendix A NQTL Factor Checklist, showing the number of days allowed for authorization durations, and replacing 'coverage' with 'prior authorization validity' in the initial and renewal criteria. Clinical updates include Eylea HD for macular edema following retinal vein occlusion, Breyanzi for relapsed or refractory marginal zone lymphoma, and new appendiceal neoplasm and cancer indications with ICD-10 codes D37.3 and Z85.038. Commercial post service claim edit policies for Trogarzo have revisions effective Feb. 1, 2026.
Aetna Clinical Policy Bulletin 0721 sets Aetna's coverage rules for intraoperative radiation therapy (IORT). Aetna considers IORT medically necessary for cervical cancer, colorectal cancer, soft tissue sarcoma (including retroperitoneal sarcoma) and uterine cancer, and considers single-fraction electron-beam IORT at the time of lumpectomy medically necessary for breast cancer when the selection criteria are met. Aetna considers IORT experimental, investigational or unproven for brain tumors and brain metastasis, cholangiocarcinoma, conjunctival neoplasms, gastric cancer, glioma, head and neck cancers, osteosarcoma, pancreatic cancer, prostate cancer, renal cell carcinoma, spinal and vertebral metastases, sporadic renal angiomyolipoma and thymoma, and notes that this list is not all-inclusive.
Aetna considers avelumab (Bavencio) medically necessary for commercial plan members with Merkel cell carcinoma, renal cell carcinoma in combination with axitinib, urothelial carcinomas, gestational trophoblastic neoplasia, endometrial carcinoma, thymic carcinoma, extranodal NK/T-cell lymphoma, colorectal adenocarcinoma, and small bowel adenocarcinoma when the criteria for each indication are met. Precertification of avelumab is required for all Aetna participating providers and members in applicable plan designs, and members who have experienced disease progression while on PD-1 or PD-L1 inhibitor therapy are not eligible. Aetna considers avelumab experimental, investigational, or unproven for all other indications, including breast cancer, non-small cell lung cancer, ovarian cancer, prostate cancer, and pancreatic cancer.
Aetna considers radiofrequency ablation (RFA) medically necessary for indications that include colorectal cancer liver metastases, colorectal cancer lung metastases of 5 cm or less where the primary colorectal tumor has been resected for cure (R0 resection), malignant lung masses in persons who are not candidates for surgical intervention, solitary hepatocellular carcinoma of 5 cm or less or multinodular early-stage HCC in members who are ineligible for or decline surgical resection or transplantation, renal cell carcinoma up to 4 cm in high-risk surgical candidates or in persons with renal insufficiency or a solitary kidney, and osteoid osteoma in individuals who remain symptomatic despite NSAIDs. Aetna considers RFA experimental, investigational, or unproven for combined RFA with transarterial chemoembolization for intermediate-stage hepatocellular carcinoma, combined endoluminal RFA and stenting for malignant biliary obstruction or stricture, combined RFA and vertebral cement augmentation for spinal metastases, endoscopic ultrasound-guided RFA for aldosterone-producing adenomas, and all other indications, including curative treatment of primary or metastatic malignant neoplasms in persons able to tolerate surgical resection, biliary obstructions or strictures, renal cysts, renal angiomyolipomas, Brunner's gland hyperplasia, and unresectable localized recurrent thyroid cancers without distant metastases.
Aetna covers durvalumab (Imfinzi) for commercial medical plans and considers it medically necessary for the listed cancer indications when that indication's criteria are met, including lung, small cell lung, biliary tract, cervical, colorectal, ampullary, pleural mesothelioma, hepatocellular, gastric, GEJ, esophageal, endometrial, bladder, and small bowel cancers. Members who have experienced disease progression while on PD-1 or PD-L1 inhibitor therapy are not considered eligible, and Aetna considers all other indications experimental, investigational, or unproven. Continuation of therapy is covered under separate reauthorization criteria that require no evidence of unacceptable toxicity or disease progression, with stated limits such as up to 12 months for unresectable stage II or III NSCLC and up to 24 months total for limited stage SCLC.
Aetna considers intraoperative radiation therapy (IORT) medically necessary for cervical cancer, colorectal cancer, soft tissue sarcoma (including retroperitoneal sarcoma), and uterine cancer, and considers single-fraction electron-beam IORT at the time of lumpectomy medically necessary for breast cancer when the selection criteria are met. For breast cancer, the criteria are a documented diagnosis of early stage (0, I or II) breast cancer, negative lymph nodes, technically clear surgical margins, and a tumor less than or equal to 5 cm in diameter. IORT is considered experimental, investigational, or unproven for brain tumors and brain metastasis, cholangiocarcinoma, conjunctival neoplasms, gastric cancer, glioma, head and neck cancers, osteosarcoma, pancreatic cancer, prostate cancer, renal cell carcinoma, spinal metastases, sporadic renal angiomyolipoma, thymoma, and vertebral metastases (the list is not all-inclusive).
Aetna's Clinical Policy Bulletin 0811 considers autologous or allogeneic hematopoietic stem cell transplant, both ablative and non-myeloablative, experimental, investigational, or unproven for the following adult solid tumors: bile duct (cholangiocarcinoma), breast, central nervous system tumors, cervix, colon, esophagus, fallopian tube, gallbladder, kidney, liver, lung, melanoma, nasopharynx, neuroendocrine tumors, pancreas, paranasal sinus, prostate, rectum, soft tissue sarcomas, stomach, thymus, thyroid, tumors of unknown primary origin, and uterus. Aetna considers autologous hematopoietic stem cell transplant medically necessary in young adults with primitive neuroectodermal tumors, medulloblastoma, and Ewing sarcoma family of tumors when criteria are met in CPB 0496.
Aetna requires precertification for ramucirumab (Cyramza) for all participating providers and members in applicable commercial plan designs. Aetna considers ramucirumab medically necessary for gastric, gastro-esophageal junction, and esophageal adenocarcinoma in members who are not surgical candidates or have unresectable locally advanced, recurrent or metastatic disease, and for NSCLC, advanced colorectal cancer with FOLFIRI or irinotecan, hepatocellular carcinoma with AFP of at least 400 ng/mL, mesothelioma with gemcitabine, and thymic carcinoma in the specified carboplatin and paclitaxel settings. Aetna considers ramucirumab experimental, investigational, or unproven for other indications, including breast, ovarian, prostate and renal cell cancers, head and neck cancer, melanoma and rheumatoid arthritis.
Aetna considers pemetrexed (Alimta, Axtle, Pemfexy, Pemrydi RTU, or generic pemetrexed) medically necessary for commercial members with the listed indications: non-squamous non-small cell lung cancer, pleural and peritoneal mesothelioma, ovarian, fallopian tube and primary peritoneal cancer, cervical cancer, bladder cancer, primary CNS lymphoma, thymoma and thymic carcinoma, thyroid cancer, and vaginal cancer. Members with squamous cell non-small cell lung cancer are not eligible, and indications such as breast, colorectal, gastric, pancreatic and small cell lung cancer are experimental, investigational, or unproven. Continuation is covered when there is no unacceptable toxicity or disease progression, and use with pembrolizumab for pleural or peritoneal mesothelioma is covered for up to 24 months total.
For commercial medical plan members, Aetna considers dostarlimab-gxly (Jemperli) medically necessary under its initial approval criteria for several mismatch repair deficient or microsatellite instability-high cancers, including endometrial, ampullary, breast, colorectal, esophageal, gastric, ovarian, pancreatic, small bowel and anal cancers. It also considers Jemperli in combination with pemetrexed and platinum chemotherapy for first-line metastatic nonsquamous non-small cell lung cancer without genomic aberrations. Members are not eligible when they have experienced disease progression while on PD-1 or PD-L1 inhibitor therapy, and all other indications are considered experimental, investigational, or unproven.
Aetna considers durvalumab (Imfinzi) medically necessary for commercial medical plans when the criteria for a listed indication are met, and considers all other indications experimental, investigational, or unproven. Precertification is required of all Aetna participating providers and members in applicable plan designs, and Aetna considers members not eligible for Imfinzi when they have experienced disease progression while on PD-1 or PD-L1 inhibitor therapy. Continuation of therapy is medically necessary when there is no evidence of unacceptable toxicity or disease progression on the current regimen, up to 12 months total for unresectable stage II or III NSCLC and up to 24 months total for limited stage SCLC.
Aetna considers albumin-bound paclitaxel (Abraxane or generic albumin-bound paclitaxel) medically necessary for the cancers listed in its initial approval criteria, including Kaposi sarcoma, breast cancer, cutaneous melanoma, endometrial carcinoma, ovarian, fallopian tube and primary peritoneal cancer, biliary tract cancers, non-small cell lung cancer, pancreatic adenocarcinoma, small bowel adenocarcinoma, uveal melanoma, ampullary adenocarcinoma, cervical cancer, bladder cancer and vaginal cancer, when each cancer's stated criteria are met. All other indications are considered experimental, investigational, or unproven, including small cell lung cancer, prostate cancer, soft-tissue sarcoma and gastric cancer. Continuation of therapy is medically necessary for an approved indication when there is no evidence of unacceptable toxicity or disease progression on the current regimen.
Aetna's criteria cover avelumab (Bavencio) for Merkel cell carcinoma as a single agent; first-line advanced renal cell carcinoma with clear cell histology in combination with axitinib; urothelial carcinomas (bladder cancer, primary carcinoma of the urethra, upper genitourinary tract tumors, and urothelial carcinoma of the prostate) as subsequent therapy or as maintenance therapy when there is no progression on first-line platinum-containing chemotherapy; gestational trophoblastic neoplasia; recurrent endometrial carcinoma (as a single agent when MSI-H or dMMR, or with axitinib when pMMR); thymic carcinoma with axitinib; relapsed or refractory extranodal NK/T-cell lymphoma; and colorectal or small bowel adenocarcinoma that is dMMR/MSI-H or POLE/POLD1 ultra-hypermutated, as a single agent or as neoadjuvant treatment of up to 6 months. Members who have experienced disease progression while on PD-1 or PD-L1 inhibitor therapy are not eligible, and all other indications are considered experimental, investigational or unproven. This policy addresses avelumab for commercial medical plans, where precertification is required and the Site of Care Utilization Management Policy applies.
Aetna's commercial coverage policy for atezolizumab (Tecentriq) and atezolizumab and hyaluronidase-tqjs (Tecentriq Hybreza) covers them for specific indications when the criteria are met. Covered indications include recurrent, advanced or metastatic non-small cell lung cancer, extensive-stage small cell lung cancer, hepatocellular carcinoma in combination with bevacizumab, BRAF V600 mutation-positive melanoma in combination with cobimetinib and vemurafenib, alveolar soft part sarcoma, and adjuvant treatment of muscle invasive bladder cancer after cystectomy when the member is positive for circulating tumor DNA molecular residual disease. Precertification is required in applicable plan designs, and the Site of Care Utilization Management Policy applies. Use for all other indications is considered experimental, investigational, or unproven, and members are not eligible after disease progression on PD-1 or PD-L1 inhibitor therapy.
FDG-PET or FDG-PET/CT may be considered medically necessary for listed cancers when specific criteria are met, such as staging or restaging of muscle-invasive bladder cancer, Ewing sarcoma and osteosarcoma, brain cancer, lymphoma, and multiple myeloma. PET for surveillance, meaning scans performed more than 6 months after completion of cancer therapy (12 months for lymphoma) in individuals without objective signs or symptoms of recurrence, is considered investigational, and fluoroestradiol F18 PET in individuals with breast cancer is considered investigational. The medically necessary situations assume that the PET results will influence treatment decisions, and if the results will not influence treatment decisions, those situations are considered not medically necessary.
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