D40.10
BillableNeoplasm of uncertain behavior of unspecified testis
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D40.10 an HCC code?
No. D40.10 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).
What This Code Means
D40.10 is the ICD-10-CM diagnosis code for neoplasm of uncertain behavior of unspecified testis. This code describes a growth or tumor found in the testicle that doctors cannot yet determine is cancer or benign (non-cancerous). It's used when a testicular lesion requires further testing or monitoring to establish its true nature. D40.10 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes (d37-d48).
D40.10 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
Use this code only when the pathology report explicitly states 'uncertain behavior' or 'unspecified behavior' - do not use for confirmed benign or malignant neoplasms.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for D40.10 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when the pathology report explicitly states 'uncertain behavior' or 'unspecified behavior' - do not use for confirmed benign or malignant neoplasms
- •If the specific testicle (right vs. left) is documented, use D40.11 or D40.12 instead; only use D40.10 when laterality is truly unspecified or unknown