Cytopathology of neoplastic meningitis: A series of 66 cases from a tertiary care center

Investigation of white blood cell characteristics in cerebrospinal fluid samples at pediatric brain tumor diagnosis

PURPOSE

The role of white blood cells (WBC) in the pediatric central nervous system (CNS) tumor microenvironment is incompletely defined. We hypothesized that the WBC profile in cerebrospinal fluid (CSF) correlates with the presence of tumor cells and prognosis in pediatric CNS tumors, as well as other patient and disease characteristics, and differs by tumor type, thus giving insight into the tumor immune response.

METHODS

We conducted a retrospective analysis of CSF WBC profiles at CNS tumor diagnosis in 269 patients at our institution. We examined total nucleated cell count, absolute counts, and percentages by WBC subtype. We compared CSF WBC values by tumor cell presence, patient vital status, tumor location, and the most common tumor types.

RESULTS

Patients who died of their tumor had a lower CSF lymphocyte percentage and a higher absolute monocyte count in CSF at diagnosis. The presence of tumor cells in CSF was associated with fewer lymphocytes and monocytes. Ventricular tumors had higher CSF lymphocyte, monocyte, macrophage, and total nucleated cell counts than extraventricular tumors. Germ cell tumors, low-grade glioma, high-grade glioma, and ependymoma had lower macrophage counts or percentages compared to other tumor types.

CONCLUSIONS

WBC profile in CSF at pediatric CNS tumor diagnosis correlates with patient prognosis and presence of metastatic cells, along with tumor type and other tumor characteristics like relationship to the ventricles. Prospective CSF profiling and study may be useful to future immunotherapy and other pediatric CNS tumor clinical trials.

Macrophages in Giemsa-stained cerebrospinal fluid specimens predict carcinomatous meningitis

Carcinomatous meningitis is a condition in which tumor cells spread to the subarachnoid space. Leukocyte counting and typing of cerebrospinal fluid (CSF) cell components are performed manually or using flow cytometry. However, a detailed analysis of these variables using cytological specimens has not yet been reported. The present study analyzed cytological specimens using Giemsa staining and whole slide imaging with computer-assisted image analysis (CAIA) to clarify the characteristics of the leukocyte population in CSF, especially in carcinomatous meningitis. Manual evaluation was performed using 280 Giemsa-stained cytological CSF specimens. For 49 samples, CAIA was used for the whole area of Papanicolaou (Pap) staining, and Giemsa-stained specimens of the same samples were imaged using a virtual slide scanner. The nuclear morphology of the leukocytes was assessed, and the total leukocyte and leukocyte subset (lymphocytes, neutrophils and macrophages) counts were evaluated. Then, the number and percentage of each leukocyte subset population were evaluated. The total leukocyte count was significantly higher in Giemsa-stained specimens compared with in Pap-stained specimens. The percentage of macrophages was significantly higher in samples from patients with non-hematological tumors compared with in samples from patients without tumors, which was confirmed by manual evaluation of the specimens. In addition, the cut-off value of the percentage of macrophages that could discriminate between the tumor history negative cases and cytologically tumor positive cases was determined, revealing that a higher proportion of macrophages reflected the existence of atypical/malignant epithelial tumor cells in CSF samples. Thus, atypical cell screening and analysis of the background characteristics of the leukocyte population should be the focus of cytological specimen screening, especially not to miss carcinomatous meningitis.

Brain Atrophy Associated with Primary Diffuse Meningeal Melanomatosis

BACKGROUND

Primary meningeal melanomatosis is a rare leptomeningeal tumor, and the diagnosis is challenging due to nonspecific clinical symptoms and radiologic findings.

CASE DESCRIPTION

A 21-year-old man presented with recurrent seizure and impaired memory. Cranial magnetic resonance imaging showed obvious brain atrophy with bilateral extensive meningeal enhancement in the supratentorial region. Diffusion-weighted imaging and fluid-attenuated inversion recovery showed slightly hyperintensive signals in the cortex. Microscopic examination revealed invasion of pigment into the Virchow-Robin space and cortex. Immunohistochemical examination of biopsy samples showed that cells were immunopositive for HMB45 and S-100 and immunonegative for melan-A with a Ki-67-positive percentage of 3%. No obvious atypia or nuclear mitosis was observed. Pathohistologic results of biopsied meninges confirmed the diagnosis of diffuse meningeal melanomatosis. The disease was aggravated with the occurrence of brain atrophy, recurrent seizure, and declined higher cortical function.

CONCLUSIONS

This case report illustrates that brain atrophy in meningeal melanomatosis is associated with a progressive decline of higher cortical function.

Cell-in-cell phenomena in cancer

Cell-in-cell structures are reported in numerous cancers, and their presence is an indicator for poor prognosis. Mechanistic studies have identified how cancer cells manage to ingest whole neighbouring cells to form such structures, and the consequences of cell-in-cell formation on cancer progression have been elucidated. In this Opinion article, we discuss how two related cell-in-cell processes, cell cannibalism and entosis, are regulated and how these mechanisms promote cancer progression. We propose that cannibalistic activity is a hallmark of cancer that results in part from selection by metabolic stress and serves to feed aggressive cancer cells.

Neoplastic Meningitis: A Study from a Tertiary Care Hospital from Coastal India

Introduction:

Neoplastic involvement of cerebrospinal fluid (CSF) secondary to known or unknown primaries elsewhere is a poor prognostic factor and is equivalent to stage IV disease.

Aim:

The aim of the study is to analyse the cytological features of neoplastic meningitis in a tertiary care center.

Materials and Methods:

A retrospective study of 400 consecutive CSF samples was done in the cytology laboratory of our hospital. The fluid obtained by spinal tap was sent for microbiological, biochemical and cytological evaluation. Smears that showed the presence of malignant cells were included in this study.

Results:

Out of 400 cases, 36 (9%) showed neoplastic meningitis. Of which, 13 cases (36%) revealed leukemic infiltration, 2 (6%) lymphomatous infiltration and 21 (58%) carcinomatous meningitis. The leukemia cases included seven cases of acute lymphoblastic leukemia and six cases of acute myeloid leukemia. Among the carcinomatous meningitis cases, eight were metastasis from carcinoma breast, six from lung carcinoma and one each from malignancies of gallbladder, stomach and retinoblastoma. Four cases were metastatic adenocarcinoma from unknown primary. Pleocytosis was a significant finding seen in 58% cases (n = 21). Elevated protein and hypoglychorrhachia was noted in 68% cases (n = 18).

Conclusion:

A combined diagnostic approach including biochemical, microbiological and pathological evaluation was useful in eliminating infectious meningitis and confirming neoplastic meningitis in these cases. Cytology should be performed on cerebrospinal specimens from all patients with known or suspected malignancy with meningismus. Detection of malignant cells on cytological examination of CSF is the diagnostic gold standard for neoplastic meningitis.

Thinprep plus Papanicolaou stain method is more sensitive than cytospin-coupled Wright Giems stain method in cerebrospinal fluid cytology for diagnosis of leptomeningeal metastasis from solid tumors

BACKGROUND

The present study was designed to determine whether the Thinprep plus Papanicolaou stain (Thinprep) method is more sensitive than the Cytospin-coupled Wright-Giemsa (WG) stain (Cytospin) method in diagnosis of leptomeningeal metastasis (LM) from malignant solid tumors in cerebrospinal fluid (CSF). We also explored if the Thinprep method could be used in the differential diagnosis of the type of primary tumor cells based on the morphology of tumor cells in CSF samples.

METHODS

The morphological features of tumor cells in fresh CSF samples were analyzed using both methods. The tumor cell detection rates were compared between the two methods.

RESULTS

Using the Thinprep method, we found that each type of tumor cells in the CSF samples had specific identifiable morphological features linked to their primary cancer origins, such as adenocarcinomas originated from the lungs, breast, and stomach, and lung squamous cell carcinomas, small cell lung cancer, large-cell neuroendocrine lung cancer, hepatocellular carcinoma, and malignant melanoma. In a retrospective study with 88 LM patients, cancer cells were detected in 80 out of the 88 CSF samples. In the comparative study with 45 LM patients, the initial detection rate of the Thinprep method was significantly higher than that of the Cytospin method (73.3% vs. 57.8%, P<0.01). The cell morphology was better preserved and subcellular structures were clearer using the Thinprep method, compared to the Cytospin method.

CONCLUSIONS

The Thinprep method is more sensitive and suitable for LM diagnosis in CSF in patients with malignant solid tumors than the Cytospin method. The Thinprep method may facilitate primary tumor detection and help design early treatment regimens for LM patients with tumors of unknown primary origin.