C09.0 is the authoritative medical code for Malignant neoplasm of tonsillar fossa. This classification is used in medical billing and clinical recording to specify the clinical criteria for malignant neoplasm of tonsillar fossa (ICD-10-CM C09.0), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Malignant neoplasm of tonsillar fossa is a billable ICD-10-CM diagnosis code C09.0. Excludes2 (not included here): malignant neoplasm of lingual tonsil C02.4; malignant neoplasm of pharyngeal tonsil C11.1. Use additional code: code to identify:; alcohol abuse and dependence F10.-; exposure to environmental tobacco smoke Z77.22; exposure to tobacco smoke in the perinatal period P96.81; history of tobacco dependence Z87.891; occupational exposure to environmental tobacco smoke Z57.31; tobacco dependence F17.-; tobacco use Z72.0.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for C09.0 in the official ICD-10-CM tabular list.
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- malignant neoplasm of lingual tonsil C02.4
- malignant neoplasm of pharyngeal tonsil C11.1
Use Additional Code
Supplementary codes the tabular list directs you to add.
- code to identify:
- alcohol abuse and dependence F10.-
- exposure to environmental tobacco smoke Z77.22
- exposure to tobacco smoke in the perinatal period P96.81
- history of tobacco dependence Z87.891
- occupational exposure to environmental tobacco smoke Z57.31
- tobacco dependence F17.-
- tobacco use Z72.0
Frequently Asked Questions (FAQ) & Clinical Guidance
Can C09.0 be reported alongside related conditions?
Per Excludes2 instructions, C09.0 and the following may both be reported when both are present: malignant neoplasm of lingual tonsil (C02.4); malignant neoplasm of pharyngeal tonsil (C11.1).
Is an additional code needed with C09.0?
Use additional code(s) to specify: code to identify:; alcohol abuse and dependence (F10.-); exposure to environmental tobacco smoke (Z77.22); exposure to tobacco smoke in the perinatal period (P96.81).
Codes in This Family (4)
Official ICD-10-CM classifications in the same code family as C09.0, with their registry titles.
- C09 — Malignant neoplasm of tonsil
- C09.1 — Malignant neoplasm of tonsillar pillar (anterior) (posterior)
- C09.8 — Malignant neoplasm of overlapping sites of tonsil
- C09.9 — Malignant neoplasm of tonsil, unspecified
Neoplasm Table Sites (3)
Anatomical sites from the official ICD-10-CM Table of Neoplasms that map to this code, with the matching behavior column.
- Neoplasm, neoplastic, fossa (of), tonsillar — Malignant, Primary
- Neoplasm, neoplastic, glossopharyngeal sulcus — Malignant, Primary
- Neoplasm, neoplastic, tonsillar fossa — Malignant, Primary
Related Codes & Numerical Sequence (Crawl Map)
Search engines and indexers are advised to traverse adjacent medical codes in this sub-chapter range to find correlated diagnoses or therapeutic procedures: