A 65-year-old man presents with a pearly, flesh-coloured nodule on the tip of his nose that has been slowly enlarging over the past year. The lesion intermittently crusts and bleeds but is not painful. He reports extensive sun exposure throughout his life, having worked outdoors as a builder, and has previously had non-melanoma skin cancers excised from his forearms. On examination, the lesion is dome-shaped, well-defined, and telangiectatic, with a shallow central ulcer. There are no palpable regional lymph nodes, and the remainder of his skin examination reveals signs of solar damage but no other suspicious lesions.
What is the most likely diagnosis?
Correct Answer
A. Basal cell carcinoma
Explanation of Correct Answer
A. Basal cell carcinoma – Correct
This presentation is classic for basal cell carcinoma (BCC), the most common skin malignancy in Australia. The lesion’s pearly appearance, telangiectatic vessels, and intermittent ulceration on a sun-exposed area are key diagnostic features. BCCs are locally invasive but rarely metastasise, and the most common subtype (nodular BCC) typically presents on the nose, face, or scalp in older individuals with chronic sun exposure.
In the Australian context, early diagnosis and surgical excision are the mainstays of management. RACGP and Cancer Council guidelines recommend complete excision with histopathological confirmation to reduce recurrence. The risk factors in this case—fair skin, significant sun exposure, and previous non-melanoma skin cancers—further support this diagnosis.
Explanation of Incorrect Options
B. Squamous cell carcinoma – Incorrect
SCC tends to present as a firm, hyperkeratotic, or ulcerated lesion that grows more rapidly than BCC. It often arises from actinic keratoses and may be painful or tender. The absence of induration or rapid progression makes SCC less likely here.
C. Actinic keratosis – Incorrect
Actinic keratoses are premalignant lesions presenting as rough, scaly macules or papules on sun-damaged skin. They are typically flat and do not ulcerate or bleed. The well-defined nodule described here is more advanced and consistent with BCC rather than a precursor lesion.
D. Melanoma – Incorrect
Melanomas usually have irregular borders, multiple colours, and asymmetry, often with pigment variation (brown, black, or blue). The lesion described lacks pigmentation and instead demonstrates features of BCC, such as translucency and telangiectasia.
Clinical and Australian Context
Basal cell carcinoma represents around 70% of all skin cancers diagnosed in Australia, with the highest incidence in sun-exposed populations, particularly in Queensland and New South Wales. The RACGP’s Red Book and Cancer Council Australia guidelines emphasize early recognition through routine skin checks, particularly in high-risk individuals with chronic UV exposure.
Given Australia’s high UV index, primary prevention through sun protection and patient education is crucial. For confirmed BCC, complete surgical excision with histological clearance remains the standard treatment. Alternative modalities (such as curettage and cautery, imiquimod, or photodynamic therapy) may be considered for superficial or low-risk lesions but are not first-line for facial nodular BCCs.
References
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RACGP. Guidelines for Preventive Activities in General Practice (Red Book). 10th ed. East Melbourne: RACGP; 2023 – Skin cancer prevention and management.
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Cancer Council Australia. Clinical Practice Guidelines for the Management of Keratinocyte Cancers. 2024.
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Therapeutic Guidelines. Dermatology eTG Complete. Melbourne: Therapeutic Guidelines Limited; 2024 – Basal cell carcinoma management.
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Murtagh J., Murtagh J.E. Murtagh’s General Practice. 8th ed. McGraw-Hill Education (Australia); 2022 – Skin malignancies and management strategies.
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GP Institute of Australia. FACRRM Fellowship MCQ & Clinical Practice Guide. Sydney: GP Institute Publications; 2025 – Dermatology and oncology chapters.