03/07/2026
Doctors thought a man had brain cancer — they found live tapeworms instead.
In a medical plot twist, brain scans initially thought to show advanced metastatic cancer in a 60-year-old man actually revealed a live infestation of pork tapeworm larvae.
When a 60-year-old man in Spain arrived at the hospital suffering from progressive headaches and behavioral changes, brain scans pointed toward terminal, metastatic cancer. Multiple abnormal spots in his brain mirrored the classic markers of tumors that had spread from elsewhere in his body. However, after extensive whole-body scans and a colonoscopy failed to detect cancer, a high-resolution MRI revealed a startling alternative. The lesions were actually fluid-filled cysts containing the larvae of 'Taenia solium', or the pork tapeworm—a parasitic brain infection known as neurocysticercosis.
Remarkably, the patient had no history of travel to regions where the parasite is endemic. Researchers believe he may have accidentally ingested microscopic tapeworm eggs years prior, possibly through contact with infected coworkers or contaminated food. While eating undercooked pork typically causes a standard intestinal tapeworm, swallowing the parasite's microscopic eggs—often through food or water contaminated with feces—allows the larvae to enter the bloodstream and form dangerous cysts in the brain. Fortunately, following targeted antiparasitic and anti-inflammatory treatments, the patient made a full recovery, highlighting the critical need for doctors to consider parasitic infections even when cancer seems statistically far more likely.
source: Hernández-Sánchez, E., Monllor, P., Gil-Fortuño, M., & Guillamón, E. (2026). Autochthonous Neurocysticercosis Brain Lesions Mimicking Metastatic Disease, Spain. Emerging Infectious Diseases, 32(7), 1220-1221.