Leukaemia cutis for clinicians, a literature review

Leukaemia cutis (LC) describes infiltration of the skin by leukaemia cells, resulting in clinically identifiable cutaneous lesions. LC has a wide range of clinical manifestations, which can make it difficult to distinguish LC from other skin changes. In a group of patients, LC can be the first manifestation of leukaemia, therefore skin biopsy is crucial for the diagnosis. In this mini review, we discuss various types of leukaemia most frequently represented in leukaemia cutis, in both children and adults and skin changes in multiple myeloma, focusing on the clinical presentation of LC and prognosis in patients.

Specific cutaneous infiltrates in patients with haematological neoplasms: a retrospective study with 49 patients

BACKGROUND

Haematological neoplasms account for around 9% of all cancers, and they are recognised as an important cause of skin infiltration. However, studies analysing cutaneous metastasis of haematological neoplasms are scarce. We describe the clinical spectrum and outcomes of specific cutaneous manifestations of leukaemias, lymphomas, multiple myeloma (MM), and blastic plasmacytoid dendritic cell neoplasm (BPDN) and make a review of the literature.

METHODS

Data from 49 patients diagnosed with secondary cutaneous infiltration of systemic haematological neoplasms over the last 10 years in a tertiary dermatology centre were retrospectively collected, and clinical-evolutive features were analysed.

RESULTS

Most cases were lymphoma (44.9%, n = 22), followed by leukaemia cutis (38.8%, n = 19), secondary plasmacytoma (10.2%, n = 5) and BPDN (6.1%, n = 3). Nodules were the predominant type of lesion, and most patients presented with multiple (≥3) lesions. In 51% (n = 25) of cases, cutaneous infiltration was detected before the diagnosis of the underlying malignancy. The patients in diverse nosological groups did not differ in terms of survival (P = 0.052).

CONCLUSIONS

We recognise the clinical heterogeneity of specific cutaneous infiltrates. The high proportion of cases in which skin involvement was key to the diagnosis of systemic malignancy emphasises the role of the dermatologist in recognising and correctly managing these patients.

Neutrophilic dermatosis: a new skin manifestation and novel pathogenic variant in a rare autoinflammatory disease

Sideroblastic anaemia, B-cell immunodeficiency, periodic fever and developmental delay (SIFD) is caused by mutations of TRNT1, an enzyme essential for mitochondrial protein synthesis, and has been reported in 23 cases. A 6-month-old girl was evaluated with recurrent fever, failure to thrive, skin lesions and anaemia. She received blood transfusions and empirical antibiotics. Skin lesions, previously interpreted as insect bites, consisted of numerous firm asymptomatic erythematous papules and nodules, distributed over trunk and limbs. Skin histopathology revealed an intense dermal neutrophilic infiltrate extending to the subcutaneous, with numerous atypical myeloid cells, requiring the diagnosis of leukaemia cutis, to be ruled out. Over the follow-up, she developed herpetic stomatitis, tonsillitis, lobar pneumonia and Metapneumovirus tracheitis, and also deeper skin lesions, resembling panniculitis. Hypogammaglobulinaemia was diagnosed. An autoinflammatory disease was confirmed by whole exome sequencing: heterozygous mutations for TRNT1 NM_182916 c.495_498del, p.F167Tfs * 9 and TRNT1 NM_182916 c.1246A>G, p.K416E. The patient has been treated with subcutaneous immunoglobulin and etanercept. She presented with developmental delay and short stature for age. The fever, anaemia, skin neutrophilic infiltration and the inflammatory parameters improved. We describe a novel mutation in SIFD and the first to present skin manifestations, namely neutrophilic dermal and hypodermal infiltration.

Cutaneous-group histiocytoses associated with myeloid malignancies: A systematic review of 102 cases

BACKGROUND

Histiocytoses are haematological disorders of bone marrow origin that share many biological and clinical features with haematological neoplasms. The association between histiocytoses of the cutaneous-group and myeloid malignancies is a poorly investigated topic of high biological and clinical impact.

METHODS

We performed a systematic review of the scientific literature, compliant with PRISMA guidelines, to unravel the clinical and pathological features of this intriguing association.

FINDINGS

We gathered and analysed 102 patients. Most were children with generalised cutaneous eruptions and displayed risk organ involvement (i.e. bone marrow, spleen, liver). Interestingly, all these features are uncommonly encountered in C-group histiocytosis not associated with haematological neoplasms.

CONCLUSIONS

Our review shows that generalised eruptions and risk organ involvement in cutaneous-group histiocytosis should raise a suspicion for a concomitant myeloid neoplasm both in children and in adults and warrant further investigations. A rapid recognition of this association is required to start a prompt and effective therapeutic management given the aggressive behaviour of the associated myeloid neoplasm in most instances.

Vemurafenib-induced histiocytoid neutrophilic panniculitis simulating myeloid leukaemia cutis

Neutrophilic panniculitis is an infrequent but characteristic adverse event under therapy with BRAF inhibitors (BRAFi). Since the approval of vemurafenib for treatment of metastatic melanoma in 2011, only two cases of neutrophilic panniculitis in malignancies other than melanoma have been published. Histiocytoid infiltrates of immature neutrophils resembling histiocytes or myelocytes have been reported in Sweet's syndrome and rarely in other neutrophilic dermatoses. We describe a novel variant of neutrophilic panniculitis with histiocytoid myeloid cells in an early lesion from a patient treated with vemurafenib in combination with an anti-EGFR (epidermal growth factor receptor) agent for metastatic colon carcinoma, three weeks after initiation of therapy. Recognizing this variant of panniculitis associated to BRAFi can avoid misinterpretation of the atypical subcutaneous infiltrate as myeloid leukaemia cutis.

Clinical characteristics of haematological malignancy patients diagnosed with leukaemia cutis: Experience of a single centre

BACKGROUND/OBJECTIVES

We evaluated the clinical characteristics of patients with haematological malignancies at our centre who were diagnosed with leukaemia cutis (LC). In addition, we describe the spectrum of other skin lesions, including, secondary skin malignancies and nonspecific benign skin lesions in haematological malignancy patients.

METHODS

We defined 58 skin lesions that developed in 54 inpatients hospitalised in the Department of Haematology, Trakya University Medical Faculty, Turkey. All skin lesions that developed in inpatients between 2006 and 2012 had been evaluated by a dermatologist. The patients' clinical features, skin biopsy results and therapies were obtained from hospital files. The diagnosis of LC was based on clinical features and histopathological examinations of the skin biopsy.

RESULTS

There were 11 patients with LC. Six (54.5%) had acute myeloblastic leukaemia. In nine patients (82%), LC was present at the initial presentation. Secondary skin malignancy was detected in 11 patients (five basal cell carcinoma, four Kaposi's sarcoma, one squamous cell carcinoma, one malignant melanoma); and malignancy was present in two patients (18%) at the initial presentation. Nonspecific benign skin lesions, the most frequent of which were drug eruptions, were determined in 32 of our patients. LC had a significantly higher likelihood of being present at initial presentation than other skin lesions (P < 0.01). The median survival in LC patients was quite short (4.5 months).

CONCLUSIONS

LC was usually diagnosed at the initial presentation of the patient or during the early course of the disease. Having LC was a poor prognostic factor.