Rapidly enlarging pigmented palatal lesion

§Chief complaint

Dark patch on the roof of the mouth that has grown and started bleeding

§Medical & dental history

• 01Hypertension
• 02No known skin melanoma
• 03Complete upper denture worn for 15 years

§Clinical examination

• 01Irregular, asymmetric brown-black macule with a raised nodular area 30 mm on the hard palate
• 02Satellite pigmented macules adjacent
• 03Surface ulceration with contact bleeding
• 04Firm 1.5 cm ipsilateral level II node

§ figuresFigures (1)

Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Oral Melanoma figures pending faculty review.

§Differential diagnosis

§Final diagnosis

Primary oral mucosal melanoma of the hard palate with regional nodal metastasis

Any pigmented oral lesion that is asymmetric, has irregular borders, varied colour, is enlarging or ulcerating must be biopsied immediately. Amalgam tattoo is static and often radiopaque; a melanotic macule does not grow.

§Investigations

• 01Incisional biopsy — malignant melanocytes with junctional activity
• 02Immunohistochemistry: S100, HMB-45, Melan-A, SOX10 positive
• 03MRI face and CT thorax/abdomen; PET-CT for staging
• 04BRAF and KIT mutation testing

§Treatment plan

• 01Radical surgical excision with wide margins, including partial maxillectomy
• 02Neck dissection for clinically positive nodes
• 03Adjuvant radiotherapy for local control
• 04Immunotherapy (anti-PD-1) via oncology; mucosal melanoma responds less well than cutaneous

§Surgical procedure

• 01Partial maxillectomy with clear margins and ipsilateral neck dissection
• 02Immediate surgical obturator; definitive obturator at 3 months

§Histopathology report

Sheets and nests of atypical epithelioid and spindle melanocytes with prominent nucleoli and melanin pigment, junctional activity present, invasion depth 6 mm, ulceration present. S100 and HMB-45 positive. Two of 28 nodes involved.

§Follow-up & outcome

• 01Adjuvant radiotherapy and systemic immunotherapy commenced
• 023-monthly surveillance imaging
• 03Prosthetic rehabilitation with an obturator; speech and swallowing preserved

§Clinical pearls / learning points

• 01Oral mucosal melanoma has a far worse prognosis than cutaneous melanoma — 5-year survival is around 20 percent.
• 02One third arise from pre-existing pigmentation; biopsy any changing oral pigmentation.
• 03There is no validated Breslow-equivalent staging for mucosal melanoma; all lesions are considered advanced.

§Related diseases

§Similar cases