Erythema gyratum repens is a skin condition that has a strong association with internal cancers.

[1] It characteristically presents with red wavy lines, generally in older adults.

[1] These regular whirly rings rapidly and repetitively appear within existing ones, giving the impression that the rash is moving.

[6][7] Erythema gyratum repens characteristically presents as wavy red lines on the skin.

[1] These regular whirly rings rapidly and repetitively appear within existing ones, expanding outward at a rate of up to 1cm a day, giving the impression that the rash is moving.

[1] There is typically an intense itch and scale over the leading edge, which may be slightly raised.

[3] Other rare reported associations have included cryptogenic organizing pneumonia and rheumatoid arthritis.

[1] Medical imaging may locate a cancer; chest X-ray, mammogram, CT scan of pelvis and abdomen.

[1] Antihistamines may help to reduce the itch, although the role of applying a steroid cream is unclear.