ICD-10 Code for Groin Lymph Node
The ICD-10 code for an enlarged or inflamed inguinal (groin) lymph node is R59.0 (Localized enlarged lymph nodes).
Anatomic Specificity
The groin contains inguinal lymph nodes, which are the regional lymph nodes for the lower extremities, perineum, and lower abdominal wall. When coding for groin lymphadenopathy, the anatomic location is critical:
- R59.0 - Localized enlarged lymph nodes (most commonly used for inguinal/groin nodes)
- R59.1 - Generalized enlarged lymph nodes (if bilateral or part of systemic lymphadenopathy)
- R59.9 - Enlarged lymph nodes, unspecified
Clinical Context Matters
The appropriate code depends on the underlying etiology:
For Malignancy-Related Inguinal Nodes
When groin lymph nodes are involved in cancer staging, the coding becomes more specific based on the primary tumor site 1:
- Penile cancer with inguinal node involvement: Use TNM staging codes (cN1-cN3 for clinical staging, pN1-pN3 for pathological staging)
- Vulvar cancer with inguinal node involvement: Similar TNM-based coding applies 2
- Rectal cancer extending to dentate line: Inguinal nodes are considered regional lymph nodes and coded as cN stage rather than cM stage 3
For Infectious/Inflammatory Causes
- L04.1 - Acute lymphadenitis of lower limb (includes inguinal region)
- I88.8 - Nonspecific mesenteric lymphadenitis (if chronic)
Important Coding Considerations
Laterality is crucial - ICD-10 emphasizes specifying right versus left when possible 4. While R59.0 doesn't have built-in laterality modifiers, documentation should clearly indicate which groin is affected.
Avoid common pitfalls:
- Don't confuse inguinal lymphadenopathy with inguinal hernias (K40.x codes) 5
- For cancer patients, concurrent SDOH codes (Z55-Z65) may be relevant but are underutilized 6
- Code position matters - primary diagnosis codes have higher accuracy than secondary positions 7
Clinical examination findings that support R59.0 coding include 8:
- Nodes >2 cm in size
- Hard, matted, or fixed nodes (suggest malignancy or granulomatous disease)
- Duration >4 weeks
- Associated systemic symptoms (fever, night sweats, weight loss)
For routine clinical documentation of palpable or enlarged groin lymph nodes without a specific underlying diagnosis, R59.0 remains the most appropriate code.