Anaplastic lymphoma kinase-positive large B-cell lymphoma: a case report with emphasis on the cytological features of the pleural effusion.
Anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (ALK-positive LBCL) is an extremely rare distinct clinicopathological subtype of LBCL, characterized by the presence of ALK-positive monomorphic large immunoblast-like neoplastic B cells. Herein, we describe the first cytological report on ALK-positive LBCL in the pleural effusion. A 69-year-old Japanese male with a past history of malignant lymphoma of the cecum presented with progressive dyspnea and pleural effusion. Removal of the pleural effusion and aspiration of bone marrow were performed. May-Grünwald-Giemsa stain of the pleural fluid revealed abundant single or small aggregates of large-sized round cells. These cells had centrally-located large round to oval nuclei. The peculiar finding was the presence of pseudopodial cytoplasmic projections, and some neoplastic cells had eosinophilic pseudopodial cytoplasmic projections, which resembled "flaming plasma cells". Histopathological and immunohistochemical studies of the bone marrow demonstrated CD138(+), ALK1(+), CD20(-), CD79a(-), CD30(-), and IgA(+) large-sized neoplastic cells. Therefore, a diagnosis of ALK-positive LBCL was made. The peculiar finding of the present case was that most of the neoplastic cells had pseudopodial cytoplasmic projections, and some of them had eosinophilic pseudopodial cytoplasmic projections that resembled "flaming plasma cells", which has been recognized as the characteristic finding of IgA myeloma. Therefore, tumor cells that resembled "flaming plasma cells" in the pleural effusion may have had IgA in the cytoplasm. Albeit extremely rare, ALK-positive LBCL shows aggressive clinical course, thus, recognition of the cytomorphological features of this type of malignant lymphoma is important for early and correct diagnosis.
Department of Clinical Laboratory Medicine, Shiga University of Medical Science Shiga, Japan ; Division of Diagnostic Pathology, Shiga University of Medical Science Shiga, Japan.
Mitsuaki
M
Ishida
Keiko
K
Yoshida
Akiko
A
Kagotani
Muneo
M
Iwai
Miyuki
M
Yoshii
Hiroko
H
Okuno
Akiko
A
Horinouchi
Ryota
R
Nakanishi
Ayumi
A
Harada
Takashi
T
Yoshida
Takafumi
T
Okuno
Keiko
K
Hodohara
Hidetoshi
H
Okabe
D000368:Aged; D000077548:Anaplastic Lymphoma Kinase; D014408:Biomarkers, Tumor / Q000032:analysis*; D001856:Bone Marrow Examination; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D016393:Lymphoma, B-Cell / Q000150:complications / Q000201:enzymology / Q000473:pathology*; D008297:Male; D016066:Pleural Effusion, Malignant / Q000209:etiology / Q000473:pathology*; D011237:Predictive Value of Tests; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis*
D014408:Biomarkers, Tumor; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases
ALK-positive large B-cell lymphoma; pleural effusion; pseudopodial cytoplasmic projection