* * Blastic NK-Cell Leukemia / Lymphoma A Case Report Chun-Ming Lin Shu-Hui Wang Tseng-tong Kuo* Ching-Chi Chi Hsin-Chun Ho Hong-Shang Hong Blastic natural killer (NK) cell lymphoma / leukemia is a rare NK cell malignancy of unknown etiology. It occurs in multiple sites and with a propensity for skin involvement. We report such a case in a 35-year-old male suffering from erythematous and purpuric papules and plaques on his face and trunk for 6 months. A biopsy specimen of the skin showed diffuse infiltration of blast-like lymphoid cells in the dermis and subcutis. Immunohistochemical study showed the tumor cells were only positive for CD56 and CD45 and negative for other T-cell, B-cell, and myeloid cell markers. T-cell receptor (TCR) gene rearrangement was germline. In situ hybridization for Epstein-Barr virus (EBV) encoded small ribonucleic acid was negative. Aspiration specimen of the bone marrow revealed diffuse infiltration of CD56 + lymphoid cells in interstitial spaces. The diagnosis of a blastic NK-cell lymphoma / leukemia was made. Because of its rarity, the case is reported. (Dermatol Sinica 21 : 408-412, 2003) Key words: Blastic NK-cell lymphoma, CD56, EBV 35 CD56 CD45 T B T EBV CD56 ( 21 : 408-412, 2003) From the Departments of Dermatology and Pathology*, Chang Gung Memorial Hospital Accepted for publication: June 2, 2003 Reprint requests: Ching-Chi Chi, M.D., Department of Dermatology, Chang Gung Memorial Hospital-Chiayi, 6, Section West, Chia- Pu Road, Putz City, Chiayi County 613, Taiwan, R.O.C. TEL: 886-5-3621000 408
INTRODUCTION Blastic NK-cell lymphoma is characterized by its blastoid or monomorphic morphology with positive expression of CD56 and lacking EBV association. The patients usually exhibit extranodal tumors, most common in the form of skin lesions. Furthermore, it can simultaneously involve lymph node, soft tissue, peripheral blood or bone marrow. A majority of the patients show widespread diseases at the initial presentation. We herein describe a case of blastic NK-cell lymphoma / leukemia with typical clinical, histological, and immunohistochemical findings. CASE REPORT A 35-year-old male had a 6-month history of erythematous skin lesions over the face and trunk without pruritic or painful sensation. The skin lesions showed poor response to topical therapy prescribed at local medical clinics. Neither body weight loss, fever, cold sweating nor other discomforts were noted. Physical examination revealed numerous ill-defined erythematous and purpuric indurated papules and plaques over the face and trunk (Fig. 1 & 2). There was no palpable lymph node. Biopsy specimen of a skin lesion showed diffuse infiltration of monotonous, medium-sized mononuclear cells in the dermis and subcutis (Fig. 3). The tumor cells had medium to large nuclei, with fine chromatin patterns, and scanty cytoplasm (Fig. 4). The paraffin-embdded specimen was treated with citrate buffer. Monoclonal antibody of CD56 (Novocastra) (Fig. 5) and CD45 (DAKO) were positive but showed negative for CD2 (Novocastra), ccd3 (DAKO), CD4 (VENTANA), CD8 (DAKO), CD20 ( DAKO), CD30 (DAKO), CD34 (DAKO), CD68 (DAKO), CD79A (DAKO), TIA-1 and myeloperoxidase (DAKO). T cell receptor (γ) gene rearrangement was not detected. No positive identification of EBV by in situ hybridization for EBER-1 was found. The peripheral blood counts revealed normal WBC count 8500 / cmm (normal range Fig. 1 Multiple ill-defined erythematous to purpuric papules and indurated plaques on the face and trunk. Fig. 2 A purpuric infiltrative plaque on right flank. Fig. 3 A diffuse infiltrate of monotonous, medium-sized cells in the dermis(h & E, x100). Dermatol Sinica, December 2003 409
3900-10600), atypical lymphocyte 9% (normal range 0%) and mild anemia, Hb10.7 g / dl (normal range 13.5-17.5). The biochemistry study showed elevation of LDH 775 u / l (normal range 47-140), and alkaline phosphatase 304 u /l(normal range 28-94). The chest X-ray showed no active lung lesion or hilar lymphadenopathy. However, a bone marrow specimen aspirated from the left iliac crest showed diffuse infiltration of malignant cells, mostly with uniform medium-sized nuclei, clumped chromatin, scanty cytoplasm and indistinct nucleoli in the interstitial space. The malignant cells also showed positive for CD56. Therefore, Fig. 4 The tumor cells have medium-sized nuclei with a fine chromatin pattern and scanty cytoplasm(h & E, x400). Fig. 5 The lymphoid cells are positive for CD56 (immunoperoxidase, x400). we made a diagnosis of blastic NK-cell lymphoma / leukemia involving the skin and the bone marrow. After the diagnosis, the patient was then treated with 4 courses of CHOP (cyclophosphamide 750mg / m 2, doxorubicin 50mg / m 2, vincristine 2mg, and dexamethasone 8mg po q6h). However, there was no sign of remission and the skin lesions persisted. DISCUSSION Blastic NK-cell lymphoma, a relatively rare NK-cell malignancy was first described by Suchi and Mori in 1994. 1 It is unclear whether it has racial predilection such as in extranodal NK / T-cell lymphoma, nasal type. It can occur at any age, but most commonly in the middle and older-aged males. This disease tends to involve multiple sites, with a tendency for the skin showing erythematous and purpuric indurated plaques or nodules. Moreover, lymph node, soft tissue, peripheral blood or bone marrow can be simultaneously involved. A majority of patients show widespread disease at the initial presentation. Histologically, this disease is characterized by a diffuse monotonous proliferation of medium-sized cells with fine chromatin, resembling the malignant cells of lymphoblastic or myeloblastic leukemia. In Giemsa-stained touch preparations, azurophilic granules may or may not be found. A special immunophentypical feature of blastic NK cell lymphoma is the positivity of CD56 antigen, which recognizes the neural cell adhesion molecule. 2 It is a useful marker for NK and NK-like T cells. The neoplastic cells are negative for surface CD3 and positive for CD56, while CD4 and CD43 are generally expressed. CD68 is usually negative, or weakly expressed. 3-5 Furthermore, T-cell receptor genes are germline, and specific chromosomal aberrations have not been found. Frequent expression of terminal deoxynucleotidyl transferase is also reported compared with the other types of NKcell malignancy. 5, 6 410 Dermatol Sinica, December 2003
Table I. Differential diagnosis of blastic NK-cell lymphoma/leukemia Nasal-type Aggressive Blastic NK Myeloid/NK NK cell NK cell cell lymphoma/ cell precursor lymphoma lymphoma leukemia acute leukemia Morphology Polymorphic Large granular Lymphoblastoid Immature blastoid lymphocyte Extramedullary Invariable Frequent Invariable Frequent disease Specifically Skin, GI tract Liver, spleen Skin, soft tissue Lymph node affected sites Phenotype CD56+, ccd3+, CD56+, scd3-, CD56+, scd3-, CD56+, scd3-, scd3-, CD2+, CD2+, CD5-, CD4+/-, CD16+, CD7+, CD15+/-, CD5-, CD16+, CD16+/-, CD33-, CD33- HLADR+, CD16-, CD33+ HLADR+, TdT- HLADR+ TdT+/- HLADR+/-, CD34+ EBV + +/- - - Response to Sensitive to No standard Sensitive to Sensitive to chemotherapy chemotherapy therapy chemotherapy AML chemotherapy for lymphoid for lymphoid malignancy malignancy Prognosis Poor Very poor poor poor Differential diagnosis includes other CD56 positive lymphoma with cutaneous involvement. In general, lymphomas expressing CD56 are very uncommon, and encompass several clinicopathological entities including nasaltype NK / T-cell lymphoma, aggressive NK / T- cell lymphoma, myeloid / NK cell precursor leukemia and blastic NK-cell lymphoma / leukemia. 3-5, 7-9 The characteristics of these lymphomas are summarized in Table I. The clinical presentation and histopathological finding of the present case are compatible with blastic NK-cell lymphoma / leukemia. However, with consideration of the morphological similarity between lymphoblastic and myeloblastic neoplasms and the fact that CD56 may be expressed in both neoplasms, the diagnosis should only be made in the absence of commitment to the T-cell or myeloid lineages. In our case, the CD3, CD20, myeloperoxidase and CD33 were all negative, and the TCR gene rearrangement was not detected. The diagnosis of blastic NK-cell lymphoma was therefore made. In this case, no positive identification of EBV by in situ hybridization for Epstein-Barr virus encoding small ribonucleic acid was found. The nasal, nasal-type and aggressive NK-cell lymphoma, are almost invariably associated with EBV infection but blastic NK cell lymphoma has no such association. 3, 5 The relationship between these lymphomas and EBV remains unclear. The clinical course of blastic NK-cell lymphoma is aggressive with a poor response to regimens used for non-hodgkin lymphomas. Most patients die within 2 years of diagnosis despite aggressive multiregimen-chemotherapy treatment. 4 Partial response to "acute myeloid leukemia" regimens has been reported in few cases. Patients with localized skin lesions have a better prognosis. These aggressive clinical Dermatol Sinica, September 2003 411
features may be related to the expression of the multi-drug resistance gene, which is overexpressed on both normal and malignant NKcells. 10 Recently, Osamu et al found specific cytotoxic T-cell against autologous tumor cells in 2 patients, which may provide the principles to the design of immunotherapy. 11 In conclusion, we present a typical case of blastic NK-cell lymphoma / leukemia. This disease is highly malignant and until now, has no effective treatment. Appropriate therapeutic approaches to this disease should be explored. REFERENCE 1. Jaffe E, Chan JKC, Suchi J, et al.: Report of the workshop on nasal and related extranodal angiocentric T/natural killer cell lymphomas. Am J Surg Pathol 20: 103-111, 1996. 2. Hercend T, Schmidt RE: Characteristics and uses of natural killer cells. Immunol Today 9: 291, 1988. 3. Elaine SJ, Nancy LH, Harald S, et al.: WHO Classification: Tumours of Haematopoietic and Lymphoid Tissues. IARC Press: 119-126, 189-235, 2001. 4. Ritsuro S, Shigeo N: Malignancies of natural killer(nk) cell precursor: myeloid/nk cell precusor acute leukemia and blastic NK cell lymphoma/leukemia. Leuk Res 23: 615-624, 1999. 5. Chang J, Sin V, Wong K, et al.: Nonnasal Lymphoma Expressing the Natural Killer Cell Marker CD56: A clinicopathologic study of 49 cases of an uncommon aggressive neoplasm. Blood 89: 4501-4513, 1997. 6. DiGiuseppe JA, Louie DC, Williams JE, et al.: Blastic natural killer cell leukemia/lymphoma: a clinicopathologic study. Am J Surg Pathol 21: 1223-1230, 1997. 7. Naoko K, Kana Y: CD2-CD4+CD56+ hematodermic/hematolymphoid malignancy. J Am Acad Dermatol 44: 231-238, 2000. 8. Jaffe ES: Classification of natural killer cell and NK-like T-cell malignancues. Blood 87: 1207-1210, 1996. 9. Elaine SJ, Laszlo K, Shimareet K, et al.: Extranodal Peripheral T-Cell and NK-Cell Neoplasms. Am J Clin Pathol 111: S46-S55, 1999. 10. Drenou B, Lamy T, Amilot L, et al.: CD3- CD56+ non-hodgkin's lymphomas with an aggressive behavior related to multidrug resistance. Blood 89: 2966-2974, 1997. 11. Osamu Y, Masako I, Takamitus O, et al.: Killer T-cell induction in patients with blastic natural killer cell lymphoma/leukemia: implication for successful treatment and possible therapeutic strategies. Br J Hematol 113: 153-160, 2001. 412 Dermatol Sinica, December 2003