Fine-needle aspiration biopsy of Ki-1-positive anaplastic large-cell lymphoma

Cytologic and immunocytochemical findings of anaplastic large cell lymphoma: analysis of ten fine-needle aspiration specimens over a 9-year period

BACKGROUND

Anaplastic large cell lymphoma (ALCL) has raised much controversy in the field of hematolymphoid pathology. Its nature is becoming better characterized with recent advances in molecular genetics. However, to the authors' knowledge, a detailed description of the fine-needle aspiration (FNA) cytology of ALCL is lacking and the application of immunocytochemical study, including immunostaining for anaplastic lymphoma kinase (ALK) protein, to cytology samples has not been studied to date.

METHODS

The authors reviewed 10 FNA specimens of ALCL from 8 patients encountered at Pamela Youde Nethersole Eastern Hospital and Queen Mary Hospital in Hong Kong over a 9-year period from early 1993 to the end of 2001. The cytologic and immunocytochemical findings (including ALK protein overexpression) of the specimens were correlated with histologic and immunohistochemical findings of surgical biopsy specimens.

RESULTS

Six of the eight patients had ALCL of the common variant, whereas the remaining two patients had ALCL of the small cell variant. FNA specimens of ALCL of the common variant yielded many loosely dispersed "hallmark" cells that contained eccentric kidney-shaped or embryo-like nuclei, several prominent rod-shaped or angulated basophilic nucleoli, and abundant amphophilic cytoplasm. "Doughnut" cells, tumor cells with multilobated nuclei, and multinucleated giant cells with a wreath-like arrangement of nuclei occasionally were found. A small number of "plasmacytoid" tumor cells, nondescript small round tumor cells, and reactive polymorphs also was present. In contrast, "plasmacytoid" cells and nondescript small to medium-sized tumor cells represented the predominant cell population in ALCL of the small cell variant. The "plasmacytoid" appearance was exaggerated further in air-dried smears. In air-dried smears, small intracytoplasmic vacuoles and scanty azurophilic granules also were noted. On immunocytochemical study performed using the cell block materials, the majority of tumor cells demonstrated membranous and paranuclear "dot-like" positivity for CD30. The staining for epithelial membrane antigen, leukocyte common antigen, and T-cell markers was variable. Positive staining for ALK protein was demonstrated beautifully in two of the cases.

CONCLUSIONS

Despite the wide morphologic spectrum of ALCL, a definitive diagnosis on the basis of FNA cytology is possible on careful interpretation of the cytologic features and a high index of suspicion. The cytologic diagnosis can be confirmed further with proper application of immunostaining to cell block sections. Immunocytochemical study for ALK protein, which provides useful prognostic information, also can be demonstrated satisfactorily using cytology samples.

Fine-needle aspiration cytopathology in diagnosis and classification of malignant lymphoma: accurate and reliable?

Diagnosis of malignant lymphoma by fine-needle aspiration biopsy (FNAB) remains a topic of skepticism and controversy. Because of the limitations of pure morphology, subclassfication of non-Hodgkin malignant lymphoma (NHML) by FNAB often requires ancillary studies which impose a challenge not typically required of other FNAB diagnoses. Despite the dubiousness expressed by many, the evidence shows that a large percentage of NHML cases can be recognized and correctly classified using FNAB. Diagnostic accuracy is dependent on several factors including the type of NHML. The emergent WHO classification of lymphomas is one that appears to more readily accommodate the cytologic methods for NHML diagnosis.

Value and limitations of fine-needle aspiration cytology in diagnosis and classification of lymphomas: A review

The fine needle aspiration (FNA) cytologic diagnosis of non-Hodgkin's lymphoma (NHL) depends upon finding a relatively monotonous population of lymphoid cells in smears. Lymphomas have successfully been classified by FNA cytology following the prevalent histologic classifications. The success rate of FNA cytology ranges from 80%-90% in diagnosis of NHL and from 67.5%-86% in its subtyping. The cytodiagnosis of Hodgkin's disease (HD) depends upon demonstration of Reed-Sternberg cells or Hodgkin's cells amongst appropriate reactive cell components. The diagnostic accuracy of FNA cytology for HD has also been invariably high (>85%). Yet, the role of cytology in primary diagnosis, subclassification and management of patients with lymphoma remains controversial. The differential diagnostic problems for NHL include a group of small round cell tumors, nonlymphoid acute leukemias and HD. Reservations have been expressed regarding the efficacy of cytology in separating florid reactive hyperplasia from low-grade malignant lymphoma. The reported cytodiagnostic accuracy for follicular lymphomas and nodular sclerosis type of HD is less compared to other subtypes of NHL and HD respectively since nodular pattern and sclerosis are strict histologic criteria which can not be appreciated in cytologic preparations. Entities like atypical lymphoproliferative disorders, peripheral T-cell lymphomas and Ki-1 positive anaplastic large cell lymphomas pose diagnostic challenges to cytologists. Despite these limitations, FNA cytology remains the first line of investigations (screening test) used in cases of lymphadenopathy. Besides initial diagnosis of lymphoma, it helps in detection of residual disease, recurrences and progression of low-grade to high-grade lymphoma, and helps in staging the disease. Availability of prior FNA cytology report facilitates the histologic diagnosis and classification of NHL. Various special ancillary techniques are now being performed on lymph node aspirates to diagnose lymphoma versus other malignancies, and to decide the functional character of lymphomas and their clonal nature. Diagn. Cytopathol. 1999;21:240-249.

Syncytial variant of nodular sclerosing Hodgkin's disease: fine-needle aspiration findings in two cases

The syncytial variant is a recently described, uncommon form of nodular sclerosing Hodgkin's disease that was previously termed "sarcomatoid." In addition to foci of typical sclerosis, it is characterized histologically by sheets or clusters of mononuclear Reed-Sternberg variants. These may be arranged around areas of necrosis with variable numbers of neutrophils. In excised material, differential diagnostic considerations include non-Hodgkin's malignant lymphoma, granulocytic sarcoma, malignant melanoma, metastatic carcinoma, thymoma, and metastatic germ cell tumor. We describe the fine-needle aspiration cytologic finding in two examples of this entity. Cohesive clusters and sheets of malignant cells with clear cytoplasm, vesicular nuclei, and prominent nucleoli are easily mistaken for metastatic carcinoma or germ cell tumor. Ancillary tests useful in this differential diagnosis are discussed.

Ki-1-positive anaplastic large cell lymphoma initially diagnosed as Hodgkin's disease by fine needle aspiration (FNA) cytology

A 45-year-old male presented with a large mass in the left axilla. FNA cytology was interpreted as Hodgkin's disease (HD), lymphocyte depletion (LD) type, but histopathologic and immunohistochemical examination showed features of Ki-1-positive anaplastic large cell lymphoma. Unrepresentative sampling by the FNA from the tumour periphery resulted in a false impression of dual reactive and neoplastic cell populations, which together with the frequent Reed-Sternberg-like cells led to the initial erroneous impression of HD. Therefore, the cytologic diagnosis of HD, LD should be approached with caution.