Basal cell carcinoma

Basal cell carcinoma (BCC), also called basal cell epithelioma, basaloid cell tumor or rodent ulcer, is a low-grade epithelial malignancy arising from epidermal basal cells or the outer root sheath of hair follicles.

Common Symptoms

Jaw cyst; slow growth; intellectual developmental delay; crusting; scleroderma-like plaque

Causes

BCC arises from basal cells of skin or adnexa (especially hair follicles), a low-grade malignancy. It is the most differentiated malignant adnexal tumor, favoring fair-skinned persons on sun-exposed head/neck sites, indicating chronic sun exposure. Other risk factors: arsenic, high-dose X-ray, coal tar derivatives, burns, scars and chronic inflammation (sinuses, stasis ulcers, hidradenitis). Immunosuppressed patients have increased risk due to impaired cell-mediated immunity and increased oncogenic-virus susceptibility; organ-transplant patients have >10-fold risk, and herpes-virus-like DNA sequences have been found in these lesions. Histologic subtypes such as sclerodermiform BCC are more common in immunosuppressed patients; superficial BCC is more common in diabetics/chronic renal failure/HIV patients. Genetic diseases (albinism, xeroderma pigmentosum, Rasmussen, Rombo, Bazex and Darier syndromes) raise BCC risk. Causes include: 1. chronic sun exposure — UV damages DNA and impairs repair; fair skin has less protective melanin; ozone depletion raises UV exposure. 2. Excess radiation — chronic radiodermatitis plus excess radiation; latency 11-28 years at 600-8875 Rad. 3. Chemicals — chronic inorganic arsenic exposure; arsenic-related skin cancer favors non-exposed sites and palms, often multiple. 4. Physical factors — unstable atrophic burn scars; chronic ulcers/sinuses/granulomas/osteomyelitis/lupus/lichen leprosy may undergo malignant transformation after years. 5. Other — hamartomas such as sebaceous nevus and syringocystadenoma papilliferum. Pathology: pluripotent basal cells differentiate in multiple directions; tumor cells resemble basal cells, oval/spindle, hyperchromatic, scant cytoplasm, ill-defined borders, inconspicuous intercellular bridges; a PAS-positive basement band separates tumor from stroma; stromal fibroblasts proliferate. Subtypes: undifferentiated (solid, pigmented, superficial, sclerosing) and differentiated (keratotic, cystic, adenoid). Eccrine epithelioma is an adenoid BCC variant differentiating toward ducts.

Treatment

Surgery; drug therapy; supportive care

Prevention

Detect and treat precancerous lesions early — this is key to prevention.

Recommended Department

It is recommended to visit the oncological surgery department; before the visit you may first book an appointment and connect with experts through this platform.

Warm reminder: The above information is provided for health education reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek care at a regular hospital in time.