An updated approach to the diagnosis of myeloid leukemia cutis

Leukemia cutis amidst a psoriatic flare: a case report

Leukemia Cutis (LC) has many clinical morphologies that present a diagnostic challenge. This case report of a 58-year-old man experiencing a flare of psoriasis elucidates the need for clinical suspicion when a history of leukemia is present. A skin biopsy revealed histopathologic findings of psoriasis and an infiltrate of mononuclear cells consistent with LC. Upon review of the literature, 2 additional cases were reported of concurrent psoriasis and LC.

Infections in Leukemia and Hematopoietic Stem Cell Transplantation

Infections are one of the most common complications in patients diagnosed with leukemia and serve as a major obstacle to treatment. Through the early 1970s, infections were the most common cause of death in patients diagnosed with acute leukemia, but improvement in treatment and supportive care over the past few decades, coupled with expanded prophylaxis and prevention regimens, have led to reduction in both the frequency and severity of infections. Regardless, due in part to an aging cancer population and the diversity of cancer treatments and procedures, infectious diseases remain a major cause of morbidity and mortality in patients with leukemia.

Multiple granulocytic sarcomas in a patient with longstanding complete remission of acute myelogenous leukemia

Granulocytic sarcoma is an extramedullary tumor composed of granulocytic precursor cells. It usually presents as a nodular mass in the course of acute myelogenous leukemia. Rarely, the tumor develops in non-hematological conditions or in a patient with complete remission from the acute myelogenous leukemia. In such cases, aleukemic granulocytic sarcoma can be a preceding sign of systemic leukemia or a first sign of hematologic relapse of leukemia. We present an unusual case of multiple granulocytic sarcomas developed in a patient with longstanding complete remission of acute myelogenous leukemia, who has not had bone marrow and peripheral blood involvement for a long time.

A case of endocapillary glomerulonephritis associated with peripheral blood natural killer cell proliferation

A 69-year-old male was admitted to our hospital due to rapidly progressive glomerulonephritis. A peripheral blood smear showed a marked increase in large granular lymphocytes. Flow cytometry analysis of the blood showed a marked increase in CD3-negative and CD56-positive natural killer (NK) cells. A renal biopsy showed a characteristic pathological pattern that involved endocapillary proliferation, a predominance of mononuclear cells and mesangiolysis. Prednisolone was administered, and the patient’s renal function subsequently improved concomitant with the amelioration of NK cell proliferation. In our case, there was evidence of a strong association between NK cell proliferation and glomerulonephritis.

How I treat extramedullary acute myeloid leukemia

Extramedullary (EM) manifestations of acute leukemia include a wide variety of clinically significant phenomena that often pose therapeutic dilemmas. Myeloid sarcoma (MS) and leukemia cutis (LC) represent 2 well-known EM manifestations with a range of clinical presentations. MS (also known as granulocytic sarcoma or chloroma) is a rare EM tumor of immature myeloid cells. LC specifically refers to the infiltration of the epidermis, dermis, or subcutis by neoplastic leukocytes (leukemia cells), resulting in clinically identifiable cutaneous lesions. The molecular mechanisms underlying EM involvement are not well defined, but recent immunophenotyping, cytogenetic, and molecular analysis are beginning to provide some understanding. Certain cytogenetic abnormalities are associated with increased risk of EM involvement, potentially through altering tissue-homing pathways. The prognostic significance of EM involvement is not fully understood. Therefore, it has been difficult to define the optimal treatment of patients with MS or LC. The timing of EM development at presentation versus relapse, involvement of the marrow, and AML risk classification help to determine our approach to treatment of EM disease.

Functions and uses of immunohistochemical stains in cutaneous infiltrates of hematopoietic origin: a review for the practicing dermatologist

BACKGROUND

Immunohistochemical stains, particularly those for cutaneous lymphomas, have similar-sounding names, which may lead to confusion among dermatologists who are not well versed in the terminology of the tools used for pathologic diagnosis. Also aiding in this is the fact that some familiar stains are constantly investigated for novel utility in different tumors, and a plethora of new stains regularly emerge in the peer-reviewed literature.

OBJECTIVE

To review the major stains encountered in dermatopathologic reports for cutaneous lymphomas. A select number of other stains are reviewed that are either new and under investigation in several cutaneous processes or have a new use described in recent reports.

METHODS

The peer-reviewed literature was searched and analyzed for the accepted purposes of using these markers.

RESULTS

All pertinent findings for these immunostains are reported with the purpose of educating the dermatology community.

CONCLUSION

This review serves as a reference to clarify potentially confusing immunohistochemical stains.

Histologic and immunohistologic characterization of skin localization of myeloid disorders: a study of 173 cases

A retrospective analysis of 173 skin biopsy specimens of myeloid leukemia cutis (MLC) was performed to determine histologic and immunophenotypic criteria that could distinguish the varied myeloid disorders from one another. For the study, 11 relevant histologic items were scored and 12 antigens were studied (CD68 [KP1], CD163, CD14, CD4, myeloperoxidase [MPO], CD33, CD117, CD34, CD56, MIB-1, CD303, and CD123). Underlying myeloid disorders were essentially acute myeloid leukemias (65.3%), chronic myelomonocytic leukemias (11.0%), and refractory anemia (10.4%). Skin lesions were de novo in 7.5%, concurrent in 26.6%, and subsequent in 60.7%. Several morphologic characteristics (density, size of tumor cells, inflammatory background) were statistically useful in distinguishing between varied myeloid disorders. De novo MLCs displayed a specific morphologic profile. Association of CD68, CD33, and MPO could diagnose 100% of the cases of MLC. However, the immunohistochemical panel could not distinguish between the varied underlying myeloid disorders, with the exception that CD123 was particularly powerful in recognizing chronic myelomonocytic leukemia and also permitted reclassification of 4 cases as blastic plasmacytoid dendritic cell neoplasm.

Leukemic vasculitis: a rare pattern of leukemia cutis

Although non-specific skin lesions are quite common in patients with leukemia, the specific infiltration of the skin by blast cells, known as leukemia cutis, is rare. Its incidence ranges from 1 to 50% and depends on the specific type of leukemia. Leukemic vasculitis represents a rare form of leukemia cutis consisting of the involvement and destruction of vessel walls by leukemic cells, which in themselves cause the vascular injury. To date, only few cases of leukemic vasculitis have been described. Here, we report two cases of this rare skin condition, one of which mimicked cutaneous polyarteritis nodosa.