Transcalvarial Cutaneous Squamous Cell Carcinoma With Dural Invasion: Social Determinants as Drivers of Advanced...

Cutaneous squamous cell carcinoma (cSCC) of the scalp is a common malignancy, particularly among older individuals with prolonged sun exposure. It is usually superficial and easy to treat with local interventions such as surgery and topical agents. In rare cases, however, untreated or advanced lesions can invade deep structures such as the calvarium, dura mater, or brain parenchyma, requiring multidisciplinary intervention. Immunosuppression from any cause, including untreated human immunodeficiency virus (HIV), significantly increases both the incidence and severity of cSCC, particularly in marginalized populations. We report a case of a 60-year-old, unhoused Caucasian male from the Sun Belt region with a history of malnutrition and longstanding, untreated HIV infection. He presented with a large, ulcerated frontoparietal scalp mass measuring 8.6 x 10.5 x 8 cm (anteroposterior × transverse × craniocaudal). Magnetic resonance imaging (MRI) of the brain revealed the mass extended through the inner table of bone into the epidural space, resulting in diffuse meningeal enhancement. Following a multi-disciplinary discussion, he underwent a complex craniotomy with bone flap removal, requiring collaborative intervention from neurosurgery, plastic surgery, and otolaryngology. After extensive surgical excision of the lesion, reconstruction was achieved using a latissimus dorsi flap, providing adequate soft tissue coverage and restoring the integrity of the scalp. This case highlights the aggressive behavior of cSCC in immunocompromised patients and the potential for extensive local invasion in the setting of delayed dermatological care. Public health interventions for the unhoused population, such as skin cancer screenings, sunscreen distribution, and support for antiretroviral therapy adherence in HIV-positive individuals, can play a critical role in reducing health disparities. Promoting early detection and prevention of skin cancer by increasing access to care can lead to improvements in overall health outcomes in this vulnerable group.