Acute myelomonocytic leukemia presenting as a primary cutaneous lymphoma of true histiocytes

Malignant histiocytic and monocytic infiltrates of the skin are seen in true histiocytic lymphomas, in malignant histiocytosis, and in monocytic leukemias. Occasionally such cutaneous lesions constitute the presenting manifestation of the underlying malignancy. We report here a patient whose first manifestation of acute myelomonocytic leukemia was a malignant histiocytic infiltrate in the skin. Cytochemical and electron microscopic data confirmed the histiocytic nature of the skin tumor, and cytochemical data documented the myelomonocytic nature of the subsequent leukemia. Purely histiocytic skin tumors do not often presage myelomonocytic leukemias, although they have developed into monocytic leukemias, and monocytic leukemias have been transformed into myelomonocytic leukemias.     

Aleukaemic leukaemia cutis presenting as a benign-appearing eruption

A 68-year-old Caucasian male presented with a 5-week history of a widespread pruritic papular eruption. Histology from a papule on the left shoulder showed a dense dermal infiltrate of large mononuclear cells which were positive for leucocyte common antigen, KP1 and PGM1, with an MIB-1 proliferating fraction of 40%, diagnostic of acute monocytic (M5) leukaemia cutis. Full blood count revealed pancytopaenia but no blasts. Bone marrow aspirate showed reduced red cell precursors and 10% blasts, consistent with myelodysplastic syndrome (refractory anaemia with excess blasts). The patient was managed with a 3 unit transfusion of packed red cells, after which his skin eruption resolved within 6 weeks and his peripheral blood counts returned to normal. No chemotherapy was administered. In conclusion, leukaemia can present in the skin, the eruption may be nonspecific and it may precede systemic involvement by either myelodysplastic syndrome or acute leukaemia.     

Aleukemic leukemia cutis presenting as benign-appearing exanthema.

Aleukemic leukemia cutis is a rare condition characterized by the infiltration of the skin by leukemic cells before their appearance in the peripheral blood or bone marrow. We report here a 62-year-old seemingly healthy patient who presented with disseminated erythematous maculae. A skin biopsy showed leukemia cutis of monocytic type. No involvement of bone marrow or peripheral blood was found. The patient developed acute monocytic leukemia 7 months later. We present this case to illustrate how leukemia cutis can masquerade as a clinically benign-appearing cutaneous eruption without leukemic changes in blood or bone marrow. To confirm the diagnosis of aleukemic leukemia cutis, immunohistochemistry of the skin lesions as well as a complete staging procedure is necessary.     

Acute monocytic leukemia presenting as cutaneous involvement

Specific cutaneous lesions appearing during acute monocytic leukemia (AMoL) are more frequent than those associated with other types of leukemia. However, skin involvement preceding the presence of leukemic cells in the peripheral blood is quite rare. In this paper, we describe a case where a 25-year-old male had multiple infiltrative erythemas and nodules on his arms. Histologically, the nodules were formed by masses of tumor cells in the dermis. Peripheral-blood tests revealed no abnormalities, but bone marrow aspiration from the sternum led to a diagnosis of AMoL. The diagnosis of specific cutaneous lesions of AMoL was confirmed by the results of cytochemical studies of bone marrow smears, and cutaneous nodules of cutaneous biopsy specimens led to early diagnosis. Complete remission was achieved with combination chemotherapy and peripheral blood stem cell transplantation. Copyright (R) 2000 S. Karger AG, Basel     

Acute myelomonocytic leukemia revealed by a chickenpox-like rash

An unusual case of leukemia cutis is presented. A 42-year-old man presented with a vesicular skin rash mimicking chickenpox. Skin biopsy firmly ruled out the diagnosis of varicella and revealed an infiltration of the superficial derma by myeloblasts. Bone marrow aspirates confirmed the diagnosis of acute myelomonocytic leukemia (type M4).     

Chronic lymphocytic leukemia presenting as cutaneous and bone involvement

An 84‐year‐old man had a 3‐year history of a progressive, painless, papulonodular eruption, that was particularly prominent on the face and extremities. Physical examination revealed firm, bluish‐red nodules and plaques, located on the tip of the nose, the cheeks, ears, and distal digits. Skin lesions produced a leonine facies ( Fig. 1 ), deformities of the fingers and toes, finger clubbing, and onyxis. An identical lesion was seen on a postoperational scar on the left cheek. The mucous membranes were spared. The patient had anterior and posterior cervical and bilateral axillary lymphadenopathy and splenomegaly.

Figure 1 Open in figure viewer PowerPoint Leonine facies     

Chronic myelomonocytic leukemia masquerading as cutaneous indeterminate dendritic cell tumor: Expanding the spectrum of skin lesions in chronic myelomonocytic leukemia

Chronic myelomonocytic leukemia (CMML) is a hematopoietic stem cell neoplasm exhibiting both myelodysplastic and myeloproliferative features. Cutaneous involvement by CMML is critical to recognize as it typically is a harbinger of disease progression and an increased incidence of transformation to acute myeloid leukemia. Cutaneous lesions of CMML exhibit heterogeneous histopathologic features that can be challenging to recognize as CMML. We describe a 67‐year‐old man with a 3‐year history of CMML who had been managed on single‐agent azacitidine with stable disease before developing splenomegaly and acute onset skin lesions. Examination of these skin lesions revealed a dense infiltrate of histiocytic cells morphologically resembling Langerhans type cells (lacking frank histopathologic atypia), and with the immunophenotype of an indeterminate cell histiocytosis (S100+ CD1a+ and langerin?). Given the history of CMML, next‐generation sequencing studies were performed on the skin biopsy. These revealed a KRAS (p.G12R) mutation identical to that seen in the CMML 3 years prior, establishing a clonal relationship between the 2 processes. This case expands the spectrum for and underscores the protean nature of cutaneous involvement by CMML and underscores the importance of heightened vigilance when evaluating skin lesions of CMML patients.     

Choriocarcinoma presenting as a cutaneous metastasis

The rare presentation of choriocarcinoma as a cutaneous metastasis in a 23-year-old male is reported. Histological and immunohistochemical analysis of the biopsy material demonstrated two distinct cell populations, syncytiotrophoblasts and cytotrophoblasts, with syncytiotrophoblasts strongly positive for human chorionic gonadotropin antigen. Subsequent clinical evaluation revealed a testicular tumor with metastases to lungs, brain, liver and kidney and increased serum levels of human chorionic gonadotropin. The patient died shortly alter diagnosis due to complications of metastatic disease despite chemotherapy.     

Rhabdomyosarcoma presenting as a cutaneous nodule

Two patients with rhabdomyosarcoma presented clinically with dermal nodules on the face. The first patient was a 12-month-old girl with a 2 X 3-cm-diameter red nodule on her left cheek that had begun as a small red papule when she was 3 months old and had progressively increased in size. The second patient was a 19-year-old girl who presented with an enlarging mass on her right cheek that had begun as a pea-sized nodule three months previously. In both cases, biopsies revealed a rhabdomyosarcoma in the underlying soft tissue with extension into the overlying dermis. Rhabdomyosarcoma presenting as a dermal nodule is rare. It usually presents as an asymptomatic papule without distinctive clinical features and therefore may result in delayed diagnosis unless a biopsy is performed.     

Acral syringomas presenting as a photosensitive papular eruption

A 43-year-old woman presented with a recurrent and remitting eruption of reddish-brown papules in the sun-exposed areas of the arms and forearms that had been present for 2 years. Results of a histopathologic examination revealed syringoma. To the best of our knowledge, this is the first case report of syringomas confined to sun-exposed areas with a recurrent and remitting course over time. We also review the literature on acral syringomas.     

Multiple myeloma presenting as a novel mucocutaneous eruption

A 71-year-old woman presented with exquisitely tender mucosal erosions, a diffuse polymorphous eruption, and night sweats. Workup revealed multiple myeloma with a monoclonal IgG-kappa paraprotein in the serum. Her severe oral involvement was suggestive of paraneoplastic pemphigus, but direct and indirect immunofluorescence tests were negative. A skin biopsy showed spongiosis and a sparse perivascular lymphocytic infiltrate, with occasional CD8-positive lymphocytes in the epidermis. Her lesions improved with intravenous immune globulin. Immunohistochemical staining on the formalin-fixed biopsy specimen was strongly positive for IgG and IgG-kappa in an epidermal "chicken-wire" pattern, but negative for IgG-lambda. Her pulmonary tissue stained negative for IgG-kappa, suggesting clinical relevance of the myeloma paraprotein in her epidermis. To our knowledge, this is the first report of a multiple myeloma patient with such an eruption.     

Acute New World cutaneous leishmaniasis presenting as tuberculoid granulomatous dermatitis

Acute primary cutaneous leishmaniasis typically presents microscopically with a lymphohistiocytic infiltrate containing admixed plasma cells, parasitized macrophages and abundant organisms. Tuberculoid granulomatous changes may occur in the later phases of primary infection. A 23-year-old male presented 1 month after visiting Peru with classic clinical findings of acute primary cutaneous leishmaniasis, while histopathology showed a tuberculoid granulomatous process that lacked any organisms in hematoxylin-eosin and fungal stains. Polymerase chain reaction (PCR) analysis and tissue cultures confirmed the diagnosis of cutaneous leishmaniasis with Leishmania (Viannia) panamensis infection. A pauci-organism tuberculoid granulomatous process may uncommonly be the presenting histopathology in the acute infectious phase of cutaneous leishmaniasis. Clinicians and dermatopathologists should be aware of this atypical presentation, which may cause diagnostic confusion and delay proper treatment. PCR testing should be employed in cases with high clinical suspicion when histopathology is not definitive.     

Leukemia cutis in B-cell chronic lymphocytic leukemia presenting as an episodic papulovesicular eruption

A 53-year-old man presented with a recurrent pruritic eruption accompanied by oral sores. His past medical history was significant for subclinical B-cell chronic lymphocytic leukemia (CLL), which had never been treated. On exam, there were erythematous papules and plaques studded with vesicles on the neck, trunk, and upper extremities. Two skin biopsies showed common features of a perivascular and periadnexal lymphocytic infiltrate in the superficial to mid-dermis. Immunohistochemical staining of the lymphocytes showed co-expression of CD20, CD23, CD5, and CD43, consistent with a diagnosis of cutaneous involvement by the patient's CLL. This case highlights the importance of considering leukemia cutis in patients with underlying CLL presenting with unusual clinical features.