{"code":"C4A.2","type":"code","title":"Merkel cell carcinoma of ear and external auricular canal","codeAlso":[],"includes":[],"modern_v":"official26","codeFirst":[],"excludes1":[],"excludes2":[],"isBillable":false,"fyEffectivity":{"fy2026":true,"fy2027":true,"billableFy2026":false,"billableFy2027":false},"sibling_codes":["C4A.20","C4A.21","C4A.22"],"inclusionTerms":[],"sibling_titles":{"code":"C4A.22","title":"Merkel cell carcinoma of left ear and external auricular canal","isBillable":true},"useAdditionalCode":[],"clinicalDefinition":"Merkel cell carcinoma of ear and external auricular canal is a non-billable ICD-10-CM category code (C4A.2). A more specific billable subcode must be selected for claims submission.","officialDefinition":"Merkel cell carcinoma of ear and external auricular canal is a non-billable ICD-10-CM category code (C4A.2). A more specific billable subcode must be selected for claims submission.","seventhCharacterInstructions":[],"workflowProtocols":[],"guidelines":{"whenToUse":[],"whenNotToUse":[],"commonBillingMistakes":[],"codeComparisons":[],"documentationChecklist":[]},"domainLandscape":{"summary":"Primary diagnostic domain and clinical landscape evaluation.","keyCategories":[],"diagnosticContinuum":"Progression continuum from acute presentation to resolution."},"children":[],"hierarchy":[],"relatedCodes":[],"relevantCPTCodes":[],"documentationTips":[],"caseStudies":[],"description":"","overview":""}