Squamous Cell Carcinoma of Skin

A 62-year-old farmer from rural Maharashtra presents with a non-healing ulcer on the dorsum of his left hand for 8 months. The lesion started as a small nodule and gradually enlarged. On examination, there is a hyperkeratotic, indurated plaque with central ulceration and rolled edges. Regional lymph nodes are palpable. What is the investigation of choice to confirm the diagnosis?

A 68-year-old farmer from rural Maharashtra with fair complexion presents with a hyperkeratotic, indurated nodule on the dorsum of his left hand that has been growing for 6 months. Biopsy confirms squamous cell carcinoma of the skin. What is the most common aetiological factor responsible for this malignancy?

A 55-year-old man with a 30-year history of occupational arsenic exposure presents with multiple hyperkeratotic papules on the palms and soles, along with a 2 cm indurated nodule on the dorsum of the right hand with irregular borders and central ulceration. Dermoscopy shows a vascular pattern with arborizing vessels. Histopathology reveals infiltrative nests of atypical keratinocytes with perineural invasion. Which of the following is the most likely diagnosis?

The histopathological image shown above demonstrates features most consistent with which of the following diagnoses?

A 62-year-old man with a 2-year history of sun exposure presents with a 1.5 cm indurated nodule on the dorsum of his hand with central ulceration and raised, rolled edges. Biopsy confirms invasive SCC. Which clinical feature best distinguishes this high-risk SCC from a low-risk SCC of the same anatomical site?