A patient who completed chemotherapy a year ago presents with mucosal lesions. What is the most likely explanation?

Correct answer: A. Oral mucositis

• A. Correct per the recall key. Mucositis is the classic chemotherapy-related mucosal complication — diffuse erythema and painful ulceration of non-keratinised mucosa.
• B. Primary herpetic gingivostomatitis is a childhood illness with fever and generalised gingival involvement; recurrent intraoral herpes in an immunosuppressed adult is possible but would appear on keratinised mucosa.
• C. Malignancy must always be excluded in a persistent lesion, but a diffuse mucosal presentation does not fit.
• D. Traumatic ulceration is solitary and related to an identifiable cause.

Note: ⚑ The timing does not fit well. Mucositis is acute — it begins within days of chemotherapy and resolves within weeks of finishing. Mucosal lesions a full year later point instead to graft-versus-host disease (if transplanted), candidiasis, or a lichenoid reaction. The key is kept as recalled, but treat the timing as a flaw in the item rather than a rule to memorise.