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A 55-year-old Lebanese man, residing in Berlin for over 40 years, with no prior comorbidities or medications, presented with a 2-year history of a slowly growing tumor on the fifth toe of his right foot. The lesion initially appeared as a yellowish discoloration on the lateral nail fold. The patient could not recall any trauma. He had spent several months in Lebanon prior to onset, during which he walked barefoot indoors and on the beach, and hiked wearing sandals. He had received cryotherapy without improvement. The lesion progressed with increasing pain and recurrent infections. Clinical examination revealed a 30 x 25 mm exophytic, verrucous, yellowish tumor with hemorrhagic ulcerations, covering the entire dorsal and mediolateral aspects of the fifth right toe and resulting in complete destruction of the nail unit (Figure 1). Apart from a single small typical verruca on the plantar forefoot, no other abnormalities were found. Palpation of the inguinal lymph nodes was unremarkable. Blood infection parameters (CRP, hematology) were normal, and HIV testing was negative. X-ray showed complete osteolysis of the middle and distal phalanges and lytic erosions of the proximal phalanx head, without signs of osteomyelitis (Figure 2). Histopathological examination of the entire tumor specimen demonstrated massive well-differentiated verrucous proliferations with little atypia, marked hyperkeratosis, and extension into the deep dermis (Figure 3). Immunohistochemistry showed low mitotic activity confined to the basal layer (Ki-67). Your diagnosis? … Diagnosis: Cutaneous verrucous carcinoma The diagnosis of highly differentiated verrucous carcinoma (VC) was confirmed histologically. The patient was referred for surgical management, undergoing amputation at the fifth metatarsophalangeal joint to ensure complete excision. Ultrasound ruled out regional lymph node metastases. Verrucous carcinoma is a rare, well-differentiated variant of squamous cell carcinoma (SCC) with low metastatic potential, first described by Ackermann in 1948.1 It occurs in various cutaneous and mucosal sites, referred to by different names depending on location, such as papillomatosis cutis carcinoides,2 Buschke-Loewenstein tumor in the anogenital region,3 and carcinoma cuniculatum in palmoplantar areas.4 Histologically, it is characterized by pronounced differentiation with minimal atypia and mitoses.5 The exact pathogenesis remains unclear. Unlike typical SCC, which is usually linked to UV exposure, VC develops in sun-protected areas affecting immunocompetent individuals. Proposed triggers include chronic trauma, mechanical irritation, chronic inflammation, chemical carcinogens, and viral infections – particularly HPV in anogenital tumors.6, 7 Despite its low metastatic potential, VC can lead to infiltration of deeper tissues and invasion of the underlying bone, especially when located in areas with little surrounding tissue such as the toes and fingers. Bone involvement as in this case is reported in 9%–12.5% of plantar tumors,8 and up to 36% in nail unit cases.9 Regional lymph node and distant metastases are extremely uncommon but have been documented.6 Diagnosis is often challenging, especially with superficial biopsies, which can be mistaken for benign lesions like verruca vulgaris or other infections and tumors.5, 6 Surgical excision with tumor-free margins is the primary therapeutic approach. Mohs micrographic surgery is preferred for tissue preservation.10 Advanced cases may require wide excision or amputation. Other treatments such as laser therapy, cryotherapy, photodynamic therapy, immunotherapy, retinoids, radiotherapy and chemotherapy have limited supporting data and are reserved for special cases.6 Verrucous carcinoma remains a high diagnostic challenge. In cases of unclear, persistent or progressive wart-like tumors, refractory to various treatments over extended periods of time, VC should be considered. Often, multiple and deep biopsies encompassing the base of the tumor or in unclear cases, complete tumor excision, are necessary for accurate pathological diagnosis. Clinical-pathological correlation is essential in correctly diagnosing this rare tumor entity and unveiling the wolf in sheep's clothing. It is possible that the true incidence of this tumor entity is much higher than expected. We hope, that increased awareness will lead to earlier detection and treatment, thus improving the surgical and functional outcome for the patients. All authors declare no conflicts of interest.