Critical appraisal of fine needle aspiration cytology in tuberculous lymphadenitis.

A cytomorphologic diagnosis of tuberculous lymphadenitis by examination of needle aspirates was made in 560 of 1,471 cases of lymphadenopathy studied over two years. Cytologic features were categorized into four groups: epithelioid clusters with or without Langhans's giant cells without necrosis (32.14%), epithelioid clusters with or without Langhans's giant cells with necrosis (50.35%), occasional epithelioid cells without characteristic necrosis/giant cells (2.85%) and necrosis without epithelioid clusters or Langhans's giant cells (14.64%). While a diagnosis of tuberculous lymphadenitis was offered with confidence in the first two groups, constituting about 82.49% cases, aspirates from the third- and fourth-group patients were subjected to Ziehl-Neelsen staining for acid-fast bacilli, which was positive in 12.5% and 75.6% of cases, respectively.     

Characterization of the epithelial components in pleomorphic adenoma of the salivary gland

OBJECTIVE: To clarify the cytomorphologic characteristics of luminal epithelial cells (LEC) and neoplastic myoepithelial cells (NMC) in pleomorphic adenoma (PA). STUDY DESIGN: Imprint cytologic smears stained with Papanicolaou stain were examined in 20 patients with PA (including recurrent cases). Immunocytochemistry was performed using the antibodies of epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA); cells positive for both CEA and EMA were interpreted as LEC and those negative as NMC. RESULTS: LEC were found in 9 of 20 cases as cell clusters in various shapes or as isolated cells with ample cytoplasm. NMC were classified into four types according to their visual patterns and cytoplasmic features: type A, isolated cells with ample cytoplasm; type B, isolated naked cells; type C, cluster of cells with ample cytoplasm; and type D, cluster of cells with scant cytoplasm. NMC were found in all 20 cases, with an absolute incidence of 100%, 90%, 65% and 50%, respectively. CONCLUSION: The different features of NMC (Types A-D) are essential to a specific differential diagnosis. This classification was useful to discriminate PA from other salivary gland tumors with NMC.     

Nodular fasciitis: diagnosis by fine needle aspiration biopsy

OBJECTIVE: To describe the cytomorphologic features of nodular fasciitis that differentiate it from schwannoma. STUDY DESIGN: The cytomorphologic features of 10 cases of nodular fasciitis were compared to those of 4 cases of biopsy-proven schwannoma. Aspirate smears were evaluated for cellular cohesion, cell type and stroma. Immunoperoxidase stains were utilized in select cases. RESULTS: The cases of nodular fasciitis exhibited cohesive clusters of epithelioid to spindle-shaped cells in a background of single, intact mesenchymal cells; inflammatory cells; and myxoid stroma. In contrast, schwannomas lacked single, intact cells and inflammation. Schwannoma stroma was also myxoid but appeared more finely fibrillar, and cell clusters were notable for alternating areas of hypercellularity and hypocellularity. Immunoperoxidase stains demonstrated smooth muscle actin reactivity in 5 cases of nodular fasciitis and S-100 in 2 cases of schwannoma. CONCLUSION: Nodular fasciitis can be distinguished from schwannomas on the basis of cytomorphologic features and immunocytochemical profile. Cytologic diagnosis of nodular fasciitis is important since it obviates the need for surgical excision.     

Cytologic features of endometrial papillary serous carcinoma

Endometrial papillary serous carcinoma (EPSC) is an uncommon variant of endometrial carcinoma that histologically resembles ovarian serous carcinoma and has an aggressive clinical course. The cytomorphologic features of 17 patients with histologically confirmed EPSC of the endometrium were reviewed and compared with those of 20 patients with histologically typical endometrial adenocarcinoma (TEC). Preoperative cervicovaginal Papanicolaou smear results were available from 14 of the 17 patients with EPSC; 10 (71%) were positive, 1 (7%) was suspicious and 3 (21%) were negative for malignancy. Initial cervicovaginal smear results were available from all 20 patients with TEC; 7 (35%) were positive, 4 (20%) were atypical or suspicious and 9 (45%) were negative for malignancy. Twelve patients with EPSC had peritoneal washings or fluids examined; seven were positive and five negative. Twelve patients with TEC had peritoneal washings or fluids examined; two (17%) were positive and ten (83%) were negative. The cervicovaginal smears from patients with EPSC revealed numerous large tumor cells (with prominent nucleoli) frequently arranged in papillary clusters with background necrosis and, in two cases, amorphous material suggestive of psammoma bodies. In contrast, the smears of patients with TEC showed small to medium-sized cells with extensive phagocytosis and many background histiocytes. The diagnosis of EPSC should be considered when the cervicovaginal smear contains numerous papillary groups of large tumor cells with macronucleoli but without prominent phagocytosis, especially when structures suggestive of psammoma bodies are present. The peritoneal fluids in these patients are more often positive than in patients with TEC, a finding consistent with the propensity of EPSC to involve peritoneal surfaces.     

Epithelioid hemangioendothelioma of the lung diagnosed by transesophageal endoscopic ultrasound-guided fine needle aspiration: a case report

BACKGROUND: Epithelioid hemangioendothelioma is a rare vascular tumor of the lung and is also known as intravascular sclerosing bronchoalveolar tumor. Although it has relatively low malignant potential, extensive pulmonary involvement and systemic metastasis have been described. The cytologic features of these tumors are not very well defined, with only few case reports describing the cytologic findings of epithelioid hemangioendothelioma of the lung on fine needle aspiration. CASE: Endoscopic ultrasound-guided fine needle aspiration of a hilar mass was performed on a 25-year-old female. The cytology showed loosely cohesive sheets and clusters of epithelioid cells. The cellular features included large, irregular nuclei with nucleoli and a moderate amount of vacuolated cytoplasm. Rare cells had a suggestion of cytoplasmic lumen formation. Histologic examination of tissue fragments on the cell block revealed a tumor composed of rounded to spindled epithelioid cells in a background of light blue stroma. The endothelial differentiation was evidenced by cytoplasmic vacuoles and lumens, some of which contained erythrocytes. The endothelial nature of these cells was confirmed by positive staining with factor VIII and CD34. CONCLUSION: The cytomorphologic features of epithelioid hemangioendothelioma described in the literature and observed in our case are distinctive and can help with the interpretation of cytologic smears and prevent misdiagnosis.     

Cytologic findings of breast ductal lavage and concurrent fine needle aspiration in pleomorphic lobular carcinoma in situ: a case report

BACKGROUND: Breast ductal lavage (DL) is a noninvasive procedure for sampling ductal epithelial cells. Patients at risk for breast cancer or with prior history can be monitored by DL. This report compares cytomorphology in concurrent DL, fine needle aspiration (FNA) and histology in a case of pleomorphic lobular carcinoma in situ (PLCIS) with signet ring features. CASE: A 57-year-old woman had DL and FNA performed after quadrantectomy for lobular carcinoma in situ with signet ring cell features. DL and FNA were diagnosed as suspicious and positive for malignancy, respectively. Subsequent biopsy showed PLCIS. Cytomorphologic features of DL, FNA and histology were compared. DL showed epithelial cells in small clusters or single-file arrangement and single-lying; in FNA, single cells predominated. DL and FNA showed nuclear atypia and cytoplasmic vacuoles, the latter more prevalent in FNA. Both samples showed cells with signet ring features. The atypical epithelial cells present in DL and FNA were identical to those seen in the histologic material. CONCLUSION: Cytomorphologic findings in DL, although less striking, are comparable to those seen in FNA. Architecture, nuclear atypia and intracytoplasmic vacuoles are helpful features in DL for establishing a diagnosis of suspicious if not positive for malignancy in LCIS.     

Fine needle aspiration cytology of mammary duct ectasia: report of a case with novel cytologic and immunocytochemical findings.

BACKGROUND: Mammary duct ectasia (MDE), or periductal mastitis, is a well-defined clinical entity with a characteristic histopathologic appearance on breast biopsy specimens. However, the cytologic features of MDE have been described only recently in the cytopathology literature, and fine needle aspiration (FNA) cytologic findings are based mainly on a small number of case reports in the English-language literature. Therefore, awareness of this entity and recognition of its cytomorphologic features could aid in a more accurate diagnosis. We report the novel cytologic and immunocytochemical findings on a case of MDE that was confirmed by histologic examination on a subsequent biopsy. CASE: We report the findings of breast FNA cytology in a 50-year-old female with a mammographically and clinically suspicious lesion. Cytology displayed a paucicellular aspirate, typified by a few scattered, cohesive clusters of ductal epithelial cells with mild nuclear atypia and distinct, peripherally located myoepithelial cells. Intermingled within the ductal elements were numerous polygonal cells with abundant, finely vacuolated cytoplasm that were immunoreactive for macrophage-specific antibody, CD68. The background consisted of a variable number of foam cells and negligible amount of blood. CONCLUSION: The current case of MDE demonstrates cytomorphologic features that may pose diagnostic problems, particularly as a consequence of variable cytologic atypia this entity may present on FNA cytology. This diagnostic difficulty is compounded because of the abnormal mammographic and suspicious clinical findings that may be associated with MDE. CD68 immunoreactivity is a useful ancillary tool to verify the histiocytic, rather than epithelial and potentially neoplastic, nature of multivacuolated cells. To the best of our knowledge, there has been no prior reported case of MDE in the English-language literature studied utilizing CD68 antibody. This case report emphasizes that MDE is a heterogeneous entity with diverse cytomorphologic features. FNA cytology in conjunction with immunocytochemistry might permit accurate classification in the proper clinical setting.     

Fine needle aspiration cytology of glycogen-rich clear cell carcinoma of the breast: review of 37 cases with histologic correlation

OBJECTIVE: To analyze fine-needle aspiration cytology (FNAC) material from 37 cases of breast glycogen-rich clear cell cancer (GRCC) and correlate cytomorphologic features with histologic appearance to determine characteristics of GRCC on FNAC. STUDY DESIGN: We reviewed cytologic features of 37 cases of breast GRCC from the archives of Ege University Hospital diagnosed between 1994 and 2006. RESULTS: Thirty-seven patients with available aspirate and confirmed GRCC were identified. The female patients ranged from 32 to 81 years (mean 52 years). The initial cytologic diagnoses were adenocarcinoma for 27 and atypical or suspicious for cancer for 10. The cytologic picture was characterized by hypercellular tumor cells in loosely cohesive syncytial groups and some single cells. Most tumor cells had abundant, finely granular eosinophilic cytoplasm or foamy to clear cytoplasm with well-defined cytoplasmic membranes and moderate to marked nuclear pleomorphism with prominent nucleoli. Histologic examination confirmed all cases to be pure GRCC. ConCLUSION: Breast GRCC is a rare, distinct category with cytologic features that overlap considerably with those of other carcinomas. Awareness of variability in cytomorphologic appearance of GRCC and routine assessment for glycogen facilitate accurate diagnosis of these lesions by FNAC and enable prompt treatment of these poor-prognosis breast cancers.     

Clear cell carcinoma arising from pleomorphic adenoma of a minor salivary gland: Report of a case with fine needle aspiration, histologic and immunohistochemical findings

BACKGROUND: Malignant changes in pleomorphic adenoma (PA) of the salivary gland (carcinoma ex pleomorphic adenoma) are not common. Clear cell carcinoma is a rare form of salivary gland tumor and involves mostly minor salivary glands, especially those of the palate. Only 3 cases of clear cell carcinoma arising in PA have been reported, 2 in submandibular glands and 1 in a minor salivary gland of the palate. CASE : A 53-year-old man presented with an enlarged mass on the left side of the palate. He had a history of palate mass about 30 years earlier; it was excised and reported as PA. Since then the tumor had recurred twice in the same place; it had been excised and was diagnosed as PA again. A few years later the mass showed rapid growth over a few months. Fine needle aspiration of the mass showed epithelial clusters with bland nuclear features and myxohyaline material typical of PA. Also noted were large and small papillary, trabecular and well-circumscribed clusters of neoplastic cells with a moderate amount offoamy, vacuolated cytoplasm with distinct borders. Glandlike and acinar structures with hyaline globule material resembling cannonballs were also noted. The cytology was suspicious for malignancy. Incisional biopsy was reported as PA. Due to the suspicion of malignancy, the whole mass was excised up to the floor of the orbit. The final diagnosis was clear cell carcinoma expleomorphic adenoma. CONCLUSION: Due to nonspecific cytologic findings in clear cell carcinoma and a mixture of elements of PA in this case, we did not consider clear cell carcinoma as the malignant component.     

Fine needle aspiration of toxoplasmic lymphadenitis in an intramammary lymph node. A case report

BACKGROUND: Cytologic findings of toxoplasmic lymphadenitis (TL) have been only sporadically reported. Intramammary lymph node is an extremely rare site for TL. CASE: A 47-year-old, healthy, female presented with a breast tumor, which was aspirated. The cytomorphologic features were interpreted as suggestive of TL. Histopathology of the excisional biopsy specimen and subsequent serologic examination confirmed the diagnosis. CONCLUSION: We obtained several characteristic findings in aspiration of TL. Of these, epithelioid cell clusters and monocytoid cells were the most diagnostic.     

Fine needle aspiration cytology of leprous neuritis

OBJECTIVE: To document the cytomorphologic features of leprous neuritis and their correlation with bacterial density. STUDY DESIGN: A partly retrospective, partly prospective study of the fine needle aspiration cytology of enlarged nerves in leprosy. Cytomorphologic features of nerve aspirates from 28 patients were studied. May-Grünwald-Geimsa and Ziehl-Neelsen staining methods were employed. RESULTS: Five cytomorphologic patterns were observed in smears of nerve aspirates in 19 group I patients with concurrent skin and nerve lesions: (1) inflammation composed of epithelioid cell granulomas (5), bacillary index (BI) = 0; (2) epithelioid cell granulomas with necrosis (5), BI = 0-1+; (3) acellular necrosis (5), BI = 0-4+; (4) macrophage granuloma (3), BI = 5-6+; and (5) granulation tissue (1), BI = 1+. In 9 group II patients with pure neuritic leprosy, 3 patterns were seen: (1) epithelioid cell granulomas (5), BI 0-6+; (2) epithelioid granulomas with necrosis (1), BI = 0; and (3) acellular necrosis (3), BI = 0-6+. CONCLUSION: The entire spectrum of leprosy is seen in nerve aspirates. Necrosis is often a prominent feature. Recognition of the range of cytomorphologic patterns and their correlation with BI contribute to accurate calibration of the disease in nerves, resulting in appropriate choice of treatment.     

Cytopathology of exocrine pancreatic carcinoma in effusions.

The cytomorphologic features were analyzed in 26 fluid samples (18 peritoneal and 8 pleural fluids) obtained in vivo from 20 patients with pancreatic carcinoma. All tumors were ductal adenocarcinomas, as proven histologically on autopsy samples. The basic cytomorphologic pattern in the smears was that of a malignant glandular tumor, consisting of cell groups with various degrees of cohesiveness. The most prominent feature was a linear arrangement (the so-called "Indian file") of tumor cells showing nuclear molding; these aggregates were frequently closely associated with the flat round clusters of cells. Other nonspecific features of adenocarcinoma included eccentric hyperchromatic nuclei, abundant, often well-preserved vacuolated cytoplasm, a variable amount of fibrin and a reactive background. Review of the autopsy specimens also revealed the presence of an "Indian-file" pattern in most cases, especially when a conspicuous desmoplastic reaction was present. These findings suggest that pancreatic carcinoma should be included in the differential diagnosis of positive serous effusions showing these cytomorphologic features.     

Peripheral T-cell lymphoma not otherwise specified vs. Hodgkin's lymphoma on fine needle aspiration cytology

OBJECTIVE: To study the morphologic features of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) on fine needle aspiration cytology (FNAC) smears and to identify cytomorphologic features that would delineate them from features of cases of Hodgkin's lymphoma (HL). CONCLUSION: Fourteen cases each of PTCL, NOS, and HL with adequate FNAC smears were retrieved. These cases were analyzed for 12 cytomorphologic features: presence of atypical lymphoid cells, percentage of large lymphoid cells, lymphoid cells with cleaved/indented nuclei, typical Reed-Sternberg (RS) cells, mononuclear cells with prominent eosinophilic macronucleoli, mononuclear cells with prominent nucleoli, histiocytes, eosinophils, plasma cells, polymorphonuclear leukocytes, vessels and perivascular clustering of atypical mononuclear/atypical lymphoid cells. Each of these features was evaluated for its presence or absence and was semiquantitated on a scale from 0 to +3. RESULTS: The presence of atypical lymphoid cells with a spectrum ranging from small to intermediate and large was seen exclusively in cases of PTCL. Lymphoid cells with cleaved or indented nuclei, endothelium-lined vessels with perivascular clustering of tumor cells and absence of typical RS cells, and mononuclear cells with prominent eosinophilic macronucleoli emerged as the parameters significant in not only diagnosing cases of PTCL, NOS, but also in their delineation from cases of HL. CONCLUSION: A careful analysis of cytomorphologic features can be useful in at least suggesting a diagnosis of PTCL and help to distinguish that diagnosis from HL, which the features may mimic. Immunophenotyping and molecular studies are important in arriving at a definitive diagnosis.     

Cytomorphologic and immunocytochemical characteristics of reactive renal tubular cells in renal glomerular disease

OBJECTIVE: To investigate the morphologic characteristics and immunocytochemical reaction to vimentin of the reactive renal tubular cells (RRTCs) in renal glomerular disease. STUDY DESIGN: We prospectively evaluated the urine cytology of renal glomerular disease in 40 patients who underwent renal biopsy. The cytology and renal biopsy specimens were analyzed for vimentin immunostaining. RESULTS: A total of 40 urine samples from the 40 patients were cytologically analyzed, and RRTCs were found in 25 samples (25 of 40, 62.5%). These RRTCs showed clear or vacuolated cytoplasm, intracytoplasmic pigmented granules (hemosiderin or lipofuscin) and large nuclei with round to irregular nuclear contours and prominent nucleoli. These cells were seen singly and in acinar clusters. Occasionally RRTCs were embedded in a cast (RRTC cast). Immunocytochemicalstudy revealed RRTCs to be positive for vimentin (25 of 25, 100%). CONCLUSION: Frequently observed characteristic cytomorphologic features of RRTCs included RRTC cast, acinar cluster, vacuolated cytoplasm and intracytoplasmic pigmented granules. A diagnosis of RRTCs can be suggested based on these cytomorphologic features. However, a definitive diagnosis will require immunocytochemical confirmation for vimentin.     

Acantholytic cells exfoliated from pemphigus vulgaris of the uterine cervix. A case report

BACKGROUND: Pemphigus vulgaris of the uterine cervix is rare and almost always associated with cutaneous or mucosal lesions elsewhere on the body. Without a history of pemphigus, acantholytic cells in cervical smears may be misdiagnosed as malignant ones. CASE: A 52-year-old female presented with a vaginal discharge, and a routine cervical smear was collected for cytology. The smear displayed atypical cells lying singly and in loose clusters, having vesicular nuclei, a thin nuclear membrane, prominent nucleoli and well-defined cytoplasmic margins. These were labeled atypical glandular cells of undetermined significance, and colposcopic examination and biopsy were advised. On colposcopy vesicular lesions and erosions were noticed on the cervix. The biopsy revealed typical intact as well as denuded suprabasal bullae of pemphigus vulgaris. On reevaluation of the cytologic smear, the cytomorphologic features correlated well with the acantholytic cells of pemphigus. Thorough reexamination of the patient revealed 2 tiny vesicles on the oral mucosa that, on biopsy, confirmed the diagnosis of pemphigus vulgaris. CONCLUSION: Cytopathologists should be aware of the typical cytomorphologic features of pemphigus vulgaris and, in an appropriate clinical setting, should be able to diagnose or at least suspect this entity in even rare sites like the cervix. A false positive diagnosis of malignancy can be avoided if the cytologic findings are judiciously correlated with the history and with clinical and colposcopic examinations.     

Fine needle aspiration of toxoplasmic (Piringer-Kuchinka) lymphadenitis: a cytohistologic correlation study

OBJECTIVE: To define the cytomorphologic features of toxoplasmic lymphadenitis (TL) and to establish the diagnostic sensitivity and specificity of the cytologic diagnosis. STUDY DESIGN: A cytohistologic correlation study of 11 patients in which a histologic diagnosis of TL was available. These cases were analyzed in a blind study among other cases of nonneoplastic lymphadenopathies. The results of the study are expressed in terms of diagnostic sensitivity and specificity. Although not included in the study, 3 other cases of TL with serologic confirmation were also reviewed. RESULTS: Microgranulomas were a characteristic finding in TL. They consisted of small clusters of epithelioid histiocytes, each with abundant cytoplasm and an eccentric, oval nucleus. Diff-Quik-stained smears had cytoplasm with particularly pale staining and a homogeneous appearance. Most microgranulomas had a monotonous appearance with a few, small lymphocytes accompanying the epithelioid cells. No necrosis, suppurative changes or giant cells were present. Blind examination by 4 reviewers led to a correct diagnosis of TL in 9 of the 11 cases. Eight of the 9 cases were recognized by each of the 4 reviewers. One false positive diagnosis was made by 1 of the reviewers. The sensitivity of the diagnosis was 72.7-81.8% and the specificity 98.8-100%. CONCLUSION: This study showed high sensitivity and specificity for the cytologic diagnosis of TL. Given the appropriate clinical context, the presence of characteristic epithelioid microgranulomas permits a diagnosis of TL. The cytologic diagnosis can be easily confirmed with serologic studies, thereby avoiding biopsy.     

Fine needle aspiration cytology of epithelioid angiosarcoma: a case report

BACKGROUND: Malignant vascular tumors are rare. Few studies have described cytomorphologic features of hemangioendothelioma and angiosarcoma on fine needle aspiration cytology (FNAC). Malignant vascular tumor with epithelioid morphology can create diagnostic difficulty, as the cytology may simulate that in other nonvascular malignant tumors. We describe epithelioid angiosarcoma, diagnosed on FNAC, in which a differential diagnosis of histiocytosis and inflammatory granulation tissue was considered. CASE: A 20-year-old man presented with forehead and scalp swellings. The forehead lesion was radiologiocally associated with a lytic lesion in the bone. FNA resulted in high cellular yield, and smears revealed prominent vascular pattern with endothelial cell atypia and histiocytoid/epithelioid neoplastic cells, occasional mitotic figures and a few cells displaying nuclear grooving. Smear background showed a significant number of neutrophils. Epithelioid hemangioendothelioma/angiosarcoma, histiocytosis and inflammatory granulation tissue were considered. A cytologic diagnosis of epithelioid angiosarcoma/epithelioid hemangioendothelioma was suggested and confirmed on histopathologic and immunohistochemical examination. CONCLUSION: Cellular aspirates from malignant epithelioid endothelial tumors involving bone may be cytologically mistaken for histiocytosis and, rarely, inflammatory granulation tissue. However, prominent vascular pattern with striking endothelial cell atypia, presence of mitotic figures and careful search for presence of endothelial differentiation are helpful in accurate cytologic diagnosis.     

Fine needle aspiration of lymphadenopathy in visceral leishmaniasis

OBJECTIVE: To illustrate the cytomorphologic features of Leishmania lymphadenitis associated with visceral leishmaniasis (V/L) and post-kala-azar dermal leishmaniasis (PKDL) and to highlight the fact that Leishmania lymphadenitis must he included in the differential diagnosis of patients presenting with lymphadenopathy, particularly in areas endemic for the disease. STUDY DESIGN: Fine needle aspiration (FNA) was routinely done in 21 cases of lymphadenopathy in VL (18 cases) and PKDL (3 cases), and the detailed cytomorphologic features were correlated with the respective histopathologic findings. RESULTS: Amastigote forms of Leishman-Donovan (LD) bodies were seen in 19 cases both intracellularly, in histiocytes and multinucleate giant cells, and extracellularly. The FNA smears revealed a polymorphous population of cells composed of lymphocytes, histiocytes, plasma cells, giant cells and tingible body macrophages. In a few cases, epithelioid cell granulomas were also seen. The cytomorphologic features were confirmed and correlated on histopathology. CONCLUSION: Not all lymphadenopathy in VL and PKDL is due to Leishmania lymphadenitis. Demonstration of LD bodies on FNA smears helps with the early diagnosis of VL and PKDL with lymphadenopathy where the diseases are endemic.     

Cytomorphology of subependymal giant cell astrocytoma.

The cytomorphology of three subependymal giant cell astrocytomas (SEGA) is described. The tumors occurred in the left lateral ventricle of three males with tuberous sclerosis. The often-polarized spindle and epithelioid tumor cells possessed dense eosinophilic cytoplasm, eccentric nuclei and visible, occasionally prominent nucleoli. In addition, they displayed thick or hairlike processes and had a distinct tendency to form cohesive clusters as well as pseudorosettes. Occasional binucleate and multinucleate cells, as well as "strap" cells and nuclear cytoplasmic inclusions, were further features of this unique tumor. In cytologic terms the principal differential diagnostic considerations include gemistocytic astrocytoma, giant cell glioblastoma and ependymoma. Since, in isolation, SEGA may represent a "forme fruste" of tuberous sclerosis and since patients with tuberous sclerosis may have brain tumors other than SEGA, it is of diagnostic importance to recognize the cytomorphologic features of this essentially benign brain tumor.     

Is CSF cytology a useful diagnostic procedure in staging paediatric CNS tumours?

Objectives:  To evaluate whether there are any factors that predict malignant cells being found in paediatric cerebrospinal fluid (CSF) samples. To determine whether CSF provides useful staging information not provided by magnetic resonance imaging (MRI) in paediatric patients with primary central nervous system (CNS) malignancy.
Methods:  We compared the CSF cytology and spinal MRI staging results in paediatric patients with primary CNS malignancy at a UK tertiary referral centre, over a decade.
Results:  Of 159 CSF samples, 72 samples were from 72 patients with primary CNS malignancy with spinal MRI available for comparison. Eight of these 72 had positive cytology (seven malignant and one suspicious). All had a high clinical suspicion of tumour at the time of sampling. Of the 72 patients, only two had evidence of CSF spread on MRI spinal staging and CSF cytology; ten had MRI without cytological evidence and six had cytological without MRI evidence.
Conclusions:  In paediatric patients with primary CNS tumours, CSF cytology provides useful staging information. Spinal MRI alone may miss some patients with CSF spread who would be identified with CSF cytology.