Reliable Cerebrospinal Fluid Cytology and Immunocytochemistry Reporting over an Extended Period by the Addition of Aldehyde and Osmolyte-Based Preservative Solution.

INTRODUCTION: The cytological examination of cerebrospinal fluid (CSF) is an important investigation in the workup of various inflammatory, malignant, or traumatic disorders of the central nervous system. The cells in the CSF lyse and degenerate at a very fast rate owing to its low tonicity, buffering capacity, redox potential, and pH, making it crucial to examine it within 2 h of sampling. We have hereby designed an aliphatic aldehyde, osmolyte, metal halide, and a buffer-based solution which will preserve the cellular components of CSF for 48 h. METHODS: Thirty-nine CSF specimens were examined within 2 h of collection, and this reading was recorded as time zero reading. The CSF specimens were then divided into two tubes with (i) pre-servative:CSF ratio of 1:5; and (ii) no preservative. Total and differential leukocyte counts and immunocytochemistry were performed on the paired specimens at 24 h and 48 h and were compared with the readings at zero hours. RESULTS: The preservative-containing CSF showed significantly higher cellularity than the undiluted samples at 24 h and 48 h (p < 0.001). Median cell counts observed in the preservative-containing CSF were 5 times and 12 times higher than in the undiluted CSF. Neutrophils, lymphocytes, and RBCs showed immunopositivity for MPO, CD45, and GLUT-1 at both time intervals. CONCLUSION: Adding the prepared preservative solution to CSF in the ratio of 1:5 can optimally preserve the CSF cells for absolute and differential quantitation, morphological assessment, and immunological testing at a later date.

Neuroblastoma: Application of International Neuroblastoma Pathology Classification on fine needle aspiration cytology smears.

Background: Neuroblastoma (NB) is the fourth most common tumor of childhood. There is a paucity of literature on its subtyping of cytology and prognostic utility. Aims: We aimed to study the cytopathological features of NB on the aspirated material, subtype it, and assess the role of International Neuroblastoma Pathology Classification (INPC) classification on cytology smears in the preoperative prognosis of NB. Materials and Methods: Fifteen cases of NB reported on fine-needle aspiration cytology (FNAC) in the past 3 years were included. Detailed clinical, radiological, and cytological features were noted. Smears were assessed for characteristics such as cellularity, neuroblasts (cytoplasmic, nuclear details), rosettes, neuropil, Schwann cells, fibroblasts, calcification, and necrosis. Afterward, cases were categorized as undifferentiated (UD), poorly differentiated (PD), and differentiating (D) subtypes. Mitotic-karyorrhectic index (MKI) was calculated and correlated with histopathology. Follow-up was done to date. Results: The age ranged from 19 days to 10 years with an M: F ratio of 3:1. Twelve cases were retroperitoneal, two cervical, and one mediastinal. Metastatic disease was seen in six cases, one to the cervical, four to the bone marrow, and two to the scalp. The International Neuroblastoma Risk Group (INRG) staging system was available in all cases, out of which three were in stage L1, six in stage L2, four in stage M, and two in stage Ms. On cytology, four cases were differentiating NB, five PD NB, and six UD NB. The MKI was high (>4%) in 80% of UD, intermediate (2-4%) in 100% of PD, and low (<2%) in 75% of D cases. MKI corroborated in both histology and cytology, except in one case. Conclusion: NB can be subtyped on cytology on the basis of characteristics of neuroblasts, presence of neutrophils, rosettes, and necrosis. UD NB has a high MKI and is associated with a poor prognosis. A preoperative comprehensive reporting of NB on cytology can be very useful in guiding appropriate chemotherapy with some increment in survival. However, larger studies are needed to validate the calculation of MKI on FNA smears.

Peripheral Lymphadenopathy in Children: Cytomorphological Spectrum and Interesting Diagnoses.

OBJECTIVE: Peripheral lymphadenopathy is a common complaint in the pediatric outpatient department. Fine needle aspiration cytology is the first investigation of choice with a high sensitivity for diagnosis but cytology may be challenging in some cases. The study was planned to study the cytomorphological spectrum and discuss a few interesting cases. MATERIAL AND METHOD: 1890 paediatric subjects' up to 12 years of age with significant peripheral lymph node enlargement and an adequate cytology specimen were included in the study. Inadequate aspirates were excluded. RESULTS: The majority of children presented within 4-8 years of age with a male to female ratio of 1.7:1. The anterior cervical group was most commonly affected, followed by the posterior cervical, axillary and inguinal. Reactive lymphadenitis constituted the majority of the diagnoses, followed by Tuberculosis, acute suppurative, BCG-induced lymphadenitis, Kimura disease, Rosai-Dorfmann disease and Kikuchi-Fujimoto disease. Lymphomas and metastatic malignancies were less common, and mainly consisted of Hodgkin lymphoma, non-Hodgkin lymphoma, anaplastic large cell lymphoma, and Langerhans cell histiocytosis. Cytomorphological features of a few challenging and interesting cases have been discussed. CONCLUSION: Non neoplastic causes of lymphadenopathy predominate in the pediatric age group. A definitive diagnosis rests upon a complete clinical, radiological, microbiological, and cyto-histopathological correlation with the use of ancillary techniques wherever necessary.

Myofibromatosis.

INTRODUCTION: Myofibromatosis is a distinctive mesenchymal disorder occurring predominantly in childhood, which on microscopy shows peripheral light areas of spindle cells and central cellular areas of primitive oval to spindle cells arranged around hemagiopercytomatous vessels. PDFGRB mutations in the familial and multifocal sporadic forms and SRF-RELA fusions in the cellular variants have been identified. The index case is being presented to discuss the clinico-pathological features, differential diagnosis, and management of the lesion. CASE PRESENTATION: An 11-year-old male presented with an infraorbital mass of 3 months duration. The mass was excised and microscopy revealed the morphological features of myofibroma with tram-track SMA immunopositivity. Nodular fasciitis and fibromatosis were the differentials considered. CONCLUSION: The SRF-RELA gene fusion may represent a subset that in the future may be used to differentiate these myofibromas/myopericytomas from the ACTB-GLI fusion myopericytomas, and PDGFRB may be used to perhaps separate out familial myofibromas from other myofibromas.

Cytological diagnosis of angiomatoid fibrous histiocytoma: Report of a case and review of literature.

Angiomatoid fibrous histiocytoma (AFH) is an unusual superficially located tumor primarily affecting children and young adults. It grows slowly and most often occurs on the extremities. There is a paucity of literature on the cytological findings of AFH owing to the rarity of the lesion and its superficial location which makes it easier to perform the biopsy. Here, we present a case of AFH in a 7-year-old girl who presented with a left upper arm swelling. The cytology of this tumor along with histopathologic correlation and review of literature is discussed.

Reliable cerebrospinal fluid cytology reporting over an extended period: Is it possible by adding formol saline and ethylenediaminetetraacetic acid as cell preservative?

BACKGROUND: Reporting cerebrospinal fluid (CSF) cytology within a narrow time frame is crucial as it is often indicated in critically ill patients and moreover, the cells in CSF are highly labile and tend to decline rapidly on standing. However, due to various logistic issues, delay in reporting is inevitable at times, especially if ancillary tools are required. In this study, we examine the effect of using formol saline and ethylenediaminetetraacetic acid (EDTA) as a preservative on the cellular composition of CSF at 18, 24, and 48 hours of preservation. METHODS: Thirty CSF specimens were examined within 2 hours of collection and this reading was recorded as time zero reading. The CSF specimens were then divided in three tubes with: (a) preservative:CSF ratio of 1:1; (b) preservative:CSF ratio of 1:5; and (c) no preservative. Total and differential leucocyte counts and immunocytochemistry were performed on the three specimens at 18, 24, and 48 hours and were compared with the readings at 0 hour. RESULTS: Preserved CSF (in the ratio of 1:5) showed no significant decrease in the number of cells at 18 hours (P = .4), 24 hours (P = .3), and 48 hours (P = .1). Cellularity decreased by 8.5%, 22%, and 40% at 18, 24, and 48 hours, respectively. Cell morphology and antigenicity were well preserved at all the three time intervals. CONCLUSION: Formol saline and EDTA, when mixed with the CSF in the ratio of 1:5, can preserve significant cellularity for up to 24 hours.

Benign vascular anomalies: A transition from morphological to etiological classification.

The International Society for the Study of Vascular Anomalies (ISSVA) devised a multidisciplinary etiopathogenesis based approach to classify benign vascular anomalies into tumors and malformations. This classification scheme has major therapeutic and prognostic implications as treatment modalities differ for both the categories. Inappropriate usage of the term "hemangioma" for etiopathogenetically distinct entities is commonly seen in clinical practice leading to delivery of incorrect treatment to the patients. We aimed to study the histomorphological and immunohistochemical features of benign vascular anomalies for their precise histopathological classification. A total of 48 cases diagnosed over a period of 3.5 years were reviewed and reclassified into vascular tumors and malformations based on ISSVA classification and prototypical histopathological features. Biopsies were reviewed based on 5 histopathological criteria viz. endothelial morphology, mitotic activity, intralesional nerve bundles, intralesional inflammation, and prominent vessel type. A panel of GLUT-1, WT-1, and Ki-67 was performed in each case. Seven cases of infantile hemangioma, 4 cases each of non-involuting congenital hemangioma and pyogenic granuloma, and 33 cases of vascular malformations were diagnosed. Endothelial cell morphology (p < 0.001), mitotic activity (p < 0.001), and intralesional nerve bundles (p < 0.001) were found to be statistically significant in differentiating hemangioma from malformations. GLUT-1 (p < 0.001) and Ki-67 labeling index (p < 0.001) were useful to distinguish infantile hemangioma from vascular malformations. To conclude, the ISSVA classification of benign vascular anomalies can be reliably done on histopathology. However, every case must be interpreted in the light of clinical and radiological features.

Lipofibromatosis.

Introduction: Lipofibromatosis is a benign pediatric soft tissue tumor arising preferentially in the distal extremities. Histologically, the tumor shows abundant adipose tissue admixed with a spindle cell component, often concentrated in septal and perimysial locations. The index case is being presented to discuss the histopathological and immunohistochemical clues to differentiate it from other fibrofatty tumors of childhood.Case report: An 11-month-old male child presented with a slowly growing mass on the upper back. MRI findings were suggestive of an adipocytic tumor. Microscopy revealed a lesion composed of mature adipocytes and intervening fibrous bands with infiltration into the adjacent skeletal muscle, features of lipofibromatosis.Conclusion: Lipofibromatosis should be considered in the differential diagnosis of a pediatric fibrofatty tumor. Accurate diagnosis is essential for proper patient management as incomplete removal of the tumor may result in recurrence.