Clinical Characterization of Leukemia Cutis Presentation
Leukemia cutis (LC) is a rare condition that results from infiltration of neoplastic cells into the skin in patients with leukemia, mainly described in case reports or small case series. This study aimed to characterize the clinical presentation of LC and its association with leukemia evolution and prognosis. A single-institution retrospective review of medical records of patients with LC was performed. Biopsy-proven LC cases diagnosed in patients with leukemia were analyzed for a variety of clinical characteristics and prognosis; 46 patients met inclusion criteria. Leukemia cutis most commonly presented in patients with acute myeloid leukemia (AML), though lesions were seen in several other leukemia types. Most LC lesions were identified at initial presentation of underlying leukemia but also occurred with leukemia relapse and at other stages of treatment. Most patients died within 1 year of LC diagnosis. The clinical presentation of LC is highly variable. Lesions occur in different anatomic regions; can present as papules, nodules, or plaques; and have different associated colors and symptoms. Duration between diagnosis of leukemia and death in patients who develop LC, and between LC diagnosis and death, are highly variable. Early detection of lesions might help provide a diagnosis in patients with leukemia and potentially improve prognosis if doing so results in earlier initiation of chemotherapy.
Practice Points
- Complete and comprehensive skin examination is important in leukemia patients, as leukemia cutis (LC) lesions can present in all body sites including ocular and oral mucosa as well as the groin.
- Given the wide variability in appearance, symptoms, distribution, and stage of leukemia at presentation, dermatologists and oncologists need to keep LC in the differential diagnosis for any new skin lesion and to have a low threshold for performing skin biopsy.
- Performing thorough skin examination on leukemia patients throughout the course of their disease may help identify LC early so that treatment can be implemented in a timely fashion at initial diagnosis, first sign of relapse, or change in disease state.
Results
Demographics
Fifty-six percent (26/46) of patients were male. The average age at diagnosis of leukemia was 58 years (range, 8.5 months–84 years). Eighty-five percent of patients were white (39/46), 11% were black (5/46), 2% were Hispanic (1/46), and 2% were of unknown ethnicity (1/46).
Eighty percent (37/46) of patients with LC had AML; 3 of these patients had a prior diagnosis of chronic myeloid leukemia (CML) and 2 had myelodysplastic syndrome (MDS) that did not develop LC until after they had transitioned to AML. Other subtypes of leukemia in this patient population included acute lymphoblastic leukemia (ALL)(n=2), plasma cell leukemia (PCL)(n=2), undifferentiated leukemia (n=2), chronic lymphocytic leukemia (CLL)(n=1), myelodysplastic syndrome (n=1), and Burkitt-type leukemia (n=1).
Distribution and Morphology of LC Lesions
The clinical appearance of LC was widely variable in morphology and anatomic location (Table 1 and Figure). Eighty-four percent of LC occurrences involved more than one lesion (n=32); 14% were a solitary lesion (n=6). For the 2 patients who had 2 separate episodes of LC, the initial presentation of LC was multiple lesions; recurrent LC at relapse presented as a solitary lesion in both cases. Most LC lesions (77% [67/87]) occurred on the trunk or extremities; 23% (20/87) of LC lesions occurred on less common sites, such as the groin, face, hands, feet, and mucosa. Papules (38% [22/58]) and nodules (31% [18/58]) were the most common morphology; macules, plaques, and ulcers were observed less frequently. Clinical descriptions of LC lesions varied widely, with the most common descriptive characteristics being erythematous (57% [20/35]), violaceous (31% [11/35]), and asymptomatic (84% [32/38]). Rare descriptors included flesh colored, hyperpigmented, tender, pruritic, edema, crusting, and confluent erythematous.
Interval Between Leukemia Diagnosis and LC Diagnosis
Approximately 59% (n=27) of patients had LC as a presenting finding of their leukemia (Table 2). Twenty-two percent (n=10) developed LC at the time of leukemia relapse; 20% (n=9) developed LC during consolidation or salvage chemotherapy. Two AML patients had recurrent episodes of LC both at initial presentation of leukemia and when AML relapsed. Two other AML patients received a diagnosis of LC at the same time as a negative concurrent bone marrow biopsy (ie, aleukemic LC). Mean duration between diagnosis of leukemia and diagnosis of LC was 0.4 months (CLL), 1.0 month (ALL), 4.7 months (AML), and 7.15 months (PCL). In cases of MDS and CML transformation to AML, the interval was 6.5 and 4.9 months, respectively.
Interval Between LC Diagnosis and Death
As a whole, 17% (n=8) of patients were living at the time this article was written (eTable). Of patients who are still living, 10.9% (n=5) have AML. Looking at the cohort of patients with AML and LC, average age at AML diagnosis was 59.8 years. Average time from diagnosis of leukemia to death was 17.3 months (range, 0.6–49.6 months) for AML; 17.0 months (range, 10.0–24.0 months) for CML transformation to AML; 15.0 months (range, 12.0–18.0 months) for PCL; 14.75 months (range, 11.0–18.5 months) for undifferentiated leukemia; and 8.95 months (range, 4.2–13.7 months) for MDS transformation to AML. The interval between leukemia diagnosis and death was notably shorter for the CLL patient (4.0 months) and the deceased ALL patient (2.4 months). Mean duration between LC diagnosis and death was 11.7 months (AML), 11.2 months (undifferentiated leukemia), 9.9 months (CML transformation to AML), 2.75 months (PCL), and 2.4 months (MDS transformation to AML). The shortest intervals between LC diagnosis and death were seen in CLL (0.5 months) and ALL (0.4 months).
