History:

Case of Dr C Hester Male , aged 76.

Presents for routine skin check on advice from his plastic surgeon.
Has a history of copious SCCs and a sebaceous adenoma (without Torre-Muir syndrome).
No particular family history, no lynch syndrome in family.
Past history of Bell's asthma medication usage in childhood for life-threatening asthma.
Has had copious sun damage from working in north Queensland (Australia) at various locations, including Mary Kathleen, a uranium mine near Cloncurry.
FP2, few naevi.

A few discrete SCCs were picked up on exam and referred to the plastic surgeon for excision, and also confluent red, scaly areas on both forearms were noted.
The areas had a typical appearance of IEC under dermoscopy, however were so widespread that a biopsy was taken to confirm the clinical diagnosis.

Histology showed IEC, and Mr TY is currently being managed with topical Efudix field treatment to small sections at a time.

Bell's mixture has been used in the past to treat severe asthma and it contains varying amounts of arsenic.
It would be fair to surmise that in this case the lesions identified were arsenic-induced, but also promoted by the patients history of severe occupational sun exposure.

Although arsenic containing medications are not generally encountered in current day Australia, arsenic exposure/poisoning is still seen worldwide as a consequence of agricultural and manufacturing use. It is unknown exactly what level or length of arsenic exposure will result in neoplasms, as there seems to be a complex interplay between genetics and other risk factors (such as sun exposure).

Other cutaneous manifestations of arsenic exposure are palmar or plantar arsenical keratoses