Repigmentatinon of Grey Hair May be a Sign of Melanoma
Repigmentation of Grey Hair is an Important Sign to Know
There are many reasons why hair might repigment. Authors of recent publication report a case of scalp hair re-pigmentation as a feature of lentigo maligna (LM). LM is a variant of melanoma in situ that develops on chronically sun-damaged skin. Occasionally this tumor also invades hair follicles.
Gressler et al 2022
The patient was an 85-year-old man with a history of chronic lymphocytic leukemia and chronic myeloid leukemia. He sought medical attention for a change in the right parietal scalp. His history included prior melanoma in situ and non-melanoma skin cancer. The patient reported hair darkening on the right scalp for several months. He denied an underlying skin lesion.
Examination of the scalp revealed grey-white hair throughout except for a 0.5 cm ill-defined light brown macule with an overlying 4.5 x 3.0 cm patch of brown hair in the right parietal area Shave biopsy was performed with a resulting diagnosis of melanoma in situ, lentigo maligna type. A wide local excision was performed as definitive treatment.
The authors propose that re-pigmentation of previously white or gray hair should rise suspicion for lentigo maligna on the scalp
Several prior studies have supported the notion that re-pigmention of grey/white hair may be a sign of melanoma especially lentigo maligna in both men and women.
Lackey et al 2019
In 2019, Lackey et al published a nice report of an 86-year-old white referred regarding a 15-cm × 8-cm patch with brown and black pigmentation occupying the vertex and superior occipital scalp. Similar to The Gressler et al study, the lesion included repigmented black hairs. It was was confirmed to be a lentigo maligna.
Repigmenting hairs in a patient with lentigo maligna. FROM Lackey A et l. Repigmentation of gray hairs with lentigo maligna and response to topical imiquimod. JAAD Case Rep. 2019 Dec; 5(12): 1015–1017. Used with creative commons license
He declined treatment with surgery or radiaton. After considering all the risks and benefits, the patient started a trial of topical imiquimod 5% cream applied 6 times weekly for 12 weeks. The patient was monitored monthly and had an excellent exuberant inflammatory reaction on the area initially, which was followed with almost complete clearing of the lesion on the fifth month. Treatment was continued focusing on the areas that retained pigmentation for 4 more months with complete clearing of the lesion.
Response of patient with lentigo maligna to imiquimod. FROM Lackey A et l. Repigmentation of gray hairs with lentigo maligna and response to topical imiquimod. JAAD Case Rep. 2019 Dec; 5(12): 1015–1017. Used with creative commons license
REFERENCE
Gressler J et al. Re-pigmentation of scalp hair - A feature of early melanoma. Am J Med. 2022 Sep 25;S0002-9343(22)00711-2.
Lackey A et l. Repigmentation of gray hairs with lentigo maligna and response to topical imiquimod. JAAD Case Rep. 2019 Dec; 5(12): 1015–1017
This article was written by Dr. Jeff Donovan, a Canadian and US board certified dermatologist specializing exclusively in hair loss.