Valid for Submission
C4A.9 is a billable diagnosis code used to specify a medical diagnosis of merkel cell carcinoma, unspecified. The code C4A.9 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.
The ICD-10-CM code C4A.9 might also be used to specify conditions or terms like merkel cell carcinoma.
Unspecified diagnosis codes like C4A.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.
Tabular List of Diseases and Injuries
The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code C4A.9:
Inclusion TermsInclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
- Merkel cell carcinoma of unspecified site
- Merkel cell carcinoma NOS
Index to Diseases and Injuries
The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code C4A.9 are found in the index:
The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:
- Merkel cell carcinoma
- CARCINOMA MERKEL CELL-. a carcinoma arising from merkel cells located in the basal layer of the epidermis and occurring most commonly as a primary neuroendocrine carcinoma of the skin. merkel cells are tactile cells of neuroectodermal origin and histologically show neurosecretory granules. the skin of the head and neck are a common site of merkel cell carcinoma occurring generally in elderly patients. holland et al. cancer medicine 3d ed p1245
Diagnostic Related Groups - MS-DRG Mapping
|MS-DRG||MS-DRG Title||MCD||Relative Weight|
|595||MAJOR SKIN DISORDERS WITH MCC||09||2.0121|
|596||MAJOR SKIN DISORDERS WITHOUT MCC||09||0.9892|
The relative weight of a diagnostic related group determines the reimbursement rate based on the severity of a patient's illness and the associated cost of care during hospitalization.
Convert C4A.9 to ICD-9 Code
The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code C4A.9 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.
Information for Patients
Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common.
Anyone can get skin cancer, but it is more common in people who
- Spend a lot of time in the sun or have been sunburned
- Have light-colored skin, hair and eyes
- Have a family member with skin cancer
- Are over age 50
You should have your doctor check any suspicious skin markings and any changes in the way your skin looks. Treatment is more likely to work well when cancer is found early. If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments include surgery, radiation therapy, chemotherapy, photodynamic therapy (PDT), and biologic therapy. PDT uses a drug and a type of laser light to kill cancer cells. Biologic therapy boosts your body's own ability to fight cancer.
NIH: National Cancer Institute
[Learn More in MedlinePlus]