Brief Answer:
Differential diagnosis

Detailed Answer:
Hello,
Welcome to healthcare magic.

I understand from your query that you are concerned about a pea sized, painless lump in your husband's cheek.

I have seen the clinical picture you have attached.

I would consider a few differential diagnosis including Oral lipoma, mucous cyst, salivary gland tumour and benign mesenchymal neoplasm.
These are benign neoplasms arising from fat, mucous glands, salivary gland component and connective tissue of the oral cavity respectively.
However, since your husband is a smoker, I advise you get it excised and sent for a histopathological examination.

You could consult an ENT surgeon to do the same.

Hope this helps you.

If you have any more queries, I will be glad to assist.

Regards,
Dr. Johny Chacko

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