DISCUSSION
Patients with underlying hematologic malignancies can present with a
diversity of non-specific reactive skin lesions or specific
infiltrates.3 Leukemia cutis is a cutaneous
infiltration of neoplastic leukocytes which has multiple clinical
presentations including erythematous papules, nodules, plaques, bullae,
noduloulcerative lesions, and even erythroderma.3 The
lesions are often firm or/and hemorrhagic lesions.The most common
locations are face, head, neck, and trunk.3
In addition to usual typical skin manifestations, the recorded unusual
manifestations of leukemia cutis were summarized in retrospective study
in 2021 by Yung-WeiChang which included leonine faces, figurate
cutaneous lesions, fingertip hypertrophy, erythema nodosum, guttate
psoriasis, chronic paronychia, leukemic vasculitis, and Sister Mary
Joseph’s nodule.4
Our patient was complaining of hyperpigmneted patches on the face and
upper trunk from six months before presenting to our clinic and
unfortunately the patches were treated as skin pigmentation.
Involvement of skin can be seen in any leukemia subtype, but most
commonly seen in acute myeloid leukemia (AML) with monocytic or
myelomonocytic and chronic lymphocytic leukemia (CLL), and rarely in
chronic myeloid leukemia (CML) which can be indicative for blast
transformation.5
The diagnosis of leukemia cutis is usually achieved by histological
study and immunophenotyping.6 Histological findings
vary according to the type of leukemia, and most commonly present as
perivascular and periadnexal dermal infiltrate.6,7Additional occasional finding includes stromal fibrosis, ulceration,
dermal vessel thrombus, and subcutaneous (7).
Currently, there is no specific treatment for leukemia cutis, and
cutaneous eruption usually resolves following treatment of underlying
leukemia (8).
To our knowledge, hyperpigmented patches secondary to leukemia cutis is
rarely described in the literature. Dermatologists could have an
important role in diagnosis of internal diseases including leukemia.
Postponing the diagnosis of leukemia cutis means delaying the diagnosis
of the underlying leukemia which lead to poor prognosis. Early diagnosis
of leukemia cutis can lead to better outcomes and may direct to an
underlying malignancy.