C44.622

Squamous cell carcinoma of skin of right upper limb, including shoulder

Squamous cell carcinoma (SCC) of the skin of the right upper limb and shoulder is a malignant neoplasm originating from the epidermal keratinocytes. It is the second most common form of skin cancer and is characterized by its potential for local invasion and a higher risk of metastasis compared to basal cell carcinoma, especially when occurring on sun-exposed extremities like the arm or shoulder. In this specific anatomical location, the tumor often develops from precursor lesions such as actinic keratoses or within areas of chronic skin damage. Clinical progression involves uncontrolled growth of squamous cells, which may penetrate the basement membrane and infiltrate the dermis, eventually potentially reaching regional lymph nodes if left untreated. Chronic ultraviolet (UV) radiation is the primary driver of the DNA mutations that lead to this malignancy.

Clinical Symptoms

  • Firm, red, dome-shaped nodule on the right arm or shoulder
  • Persistent, scaly red patch with irregular borders
  • Open sore that bleeds, crusts, or fails to heal for several weeks
  • Elevated growth with a central depression or 'crater'
  • Wart-like growth that may crust or bleed
  • Tenderness, pain, or itching at the site of the lesion
  • Sudden change in an existing skin lesion or scar
  • Development of a cutaneous horn (hard, conical projection from the skin)

Common Causes

  • Chronic and cumulative exposure to ultraviolet (UV) radiation from sunlight
  • Frequent use of tanning beds and artificial UV sources
  • Fair skin phenotype (Fitzpatrick skin types I and II) with a tendency to burn
  • Immunosuppression (e.g., organ transplant recipients or HIV/AIDS)
  • Presence of precursor lesions such as actinic keratosis or Bowen's disease
  • History of multiple severe sunburns
  • Chronic skin inflammation, long-term non-healing wounds, or old burn scars
  • Exposure to industrial chemicals such as arsenic
  • Genetic syndromes such as xeroderma pigmentosum

Documentation & Coding Tips

Explicitly state the morphology as squamous cell carcinoma rather than just skin cancer or malignant lesion to ensure the specific C44.622 code is used over a less specific C44.602.

Example: A 2.2 cm ulcerated plaque on the right lateral upper arm was biopsied. Pathology report dated 10/12/2025 confirms invasive squamous cell carcinoma. Laterality is confirmed as right side. Patient has a history of actinic keratosis.

Billing Focus: Specific morphology (squamous cell) and laterality (right side) are required to support C44.622 and avoid unspecified diagnosis denials.

Define the exact anatomical location within the right upper limb, such as the shoulder, upper arm, forearm, or hand, to support the specific sub-classification.

Example: The patient presents for treatment of a biopsy-proven squamous cell carcinoma of the skin of the right shoulder. The lesion is located 3 cm distal to the acromion process.

Billing Focus: Anatomy must include the side (right) and the segment (upper limb including shoulder) to satisfy the requirements of the sixth and seventh characters of the ICD-10 code.

Document the size and depth of the lesion, as well as the presence of high-risk features like perineural invasion or poor differentiation, which impact both coding and staging.

Example: Patient has a 3.5 cm squamous cell carcinoma on the right forearm. Pathological review shows perineural invasion and a depth of 4 mm. No regional lymphadenopathy noted on palpation of the right axilla.

Billing Focus: Lesion size determines the appropriate CPT excision code range (e.g., 11600-11606), while invasion depth supports the medical necessity of more complex surgical interventions.

Clearly distinguish between primary, recurrent, or metastatic squamous cell carcinoma of the right upper limb.

Example: Patient presents with a recurrent squamous cell carcinoma of the skin of the right upper arm at the site of a previous excision from 2023. Lesion is now 1.5 cm with ill-defined borders.

Billing Focus: Recurrence should still be coded as a current malignancy (C44.622) rather than a history of code until the patient is clear of the disease after the current treatment course.

Identify any co-existing conditions that affect treatment, such as immunosuppression or chronic lymphedema in the right upper limb.

Example: The patient has a squamous cell carcinoma of the skin of the right shoulder. Treatment is complicated by the patient's status as a kidney transplant recipient on chronic immunosuppression (tacrolimus).

Billing Focus: Co-morbidities documented as affecting management support higher levels of Medical Decision Making (MDM) for E/M coding.

Relevant CPT Codes