Circulating epithelial tumor cell analysis in CSF in patients with leptomeningeal metastases.

OBJECTIVE: The primary objective was to determine the sensitivity and specificity of epithelial cell adhesion molecule (EpCAM) immunoflow cytometry circulating tumor cells (CTC) analysis in CSF in patients with suspected leptomeningeal metastases (LM). The secondary objective was to explore the distribution of driver mutations in the primary tumor, plasma, cell free CSF (cfCSF), and isolated CTC from CSF in non-small cell lung cancer (NSCLC). METHODS: We tested the performance of the CTC assay vs CSF cytology in a prospective study in 81 patients with a clinical suspicion of LM but a nonconfirmatory MRI. In an NSCLC subcohort, we analyzed circulating tumor (ct)DNA of the selected driver mutations by digital droplet PCR (ddPCR). RESULTS: The sensitivity of the CTC assay was 94% (95% confidence interval [CI] 80-99) and the specificity was 100% (95% CI 91-100) at the optimal cutoff of 0.9 CTC/mL. The sensitivity of cytology was 76% (95% CI 58-89). Twelve of the 23 patients with NSCLC had mutated epidermal growth factor receptor (EGFR). All 5 tested patients with LM demonstrated the primary EGFR driver mutation in cfCSF. The driver mutation could also be detected in CTC isolated from CSF. CONCLUSION: CTC in CSF are detected with a high sensitivity for the diagnosis of LM. ddPCR can determine EGFR mutations in both cfCSF and isolated CTC from CSF of patients with EGFR-mutated NSCLC and LM. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that EpCAM-based immunoflow cytometry analysis of CSF accurately identifies patients with LM.

Integration of rare cell capture technology into cytologic evaluation of cerebrospinal fluid specimens from patients with solid tumors and suspected leptomeningeal metastasis.

INTRODUCTION: Dissemination of tumor to the leptomeninges, subarachnoid space, and cerebrospinal fluid (CSF) is termed leptomeningeal metastasis (LM) and occurs in approximately 5% of patients with solid tumors. LM is associated with dismal clinical prognosis, and routine cytologic and radiologic methods for diagnosing LM have limited sensitivity. The CellSearch immunomagnetic rare cell capture assay is FDA-approved to detect circulating tumor cells (CTCs) in peripheral blood, but whether it may have a role in identifying CSF CTCs is still unclear. MATERIAL AND METHODS: CSF specimens from 20 patients with clinically suspected solid tumor LM collected from 2 institutions between October 2016 and January 2019 were evaluated with routine CSF cytology and underwent concurrent CTC testing with the CellSearch assay (Menarini-Silicon Biosystems, Huntingdon Valley, PA). The results of CTC testing were compared to routine CSF cytology and radiologic studies for detecting LM. RESULTS: The CellSearch assay achieved a sensitivity of 88.9% and specificity of 100% for detecting LM (using a threshold of 1 CTC/mL of CSF as the definition of a positive CTC result). One patient with negative CSF cytology but positive CTCs developed positive cytology 37 days later. CONCLUSIONS: In this proof-of-principle pilot study, we demonstrate that the CellSearch assay can be successfully integrated with the routine CSF cytologic workflow to aid in the diagnosis of solid tumor LM. Importantly, CTCs detected by this rare cell capture assay are found in a subset of patients with non-positive routine CSF cytology, which may have significant implications for patient management.

Breast cancer leptomeningeal metastasis: the results of combined treatment and the comparison of methotrexate and liposomal cytarabine as intra-cerebrospinal fluid chemotherapy.

BACKGROUND: This was a prospective observational study to assess the results of the treatment of patients with breast cancer leptomeningeal metastasis (LM) and to compare the efficacy of methotrexate and liposomal cytarabine in patients treated intrathecally by lumbar puncture. PATIENTS AND METHODS: In this prospective observational study, 149 consecutive patients with breast cancer and LM treated between the years 1999 and 2011 were assessed. Multimodality treatment methods were used: systemic therapy in 77 patients, radiotherapy in 92 patients, intrathecal methotrexate in 81 patients, and intrathecal liposomal cytarabine in 15 patients. RESULTS: The median survival of all patients was 4.2 months. The median survival of patients in whom systemic intravenous/oral treatment was used was 6 months, in those who did not have systemic treatment, the median survival was 2 months (P < .001). The median survival of patients treated with intrathecal methotrexate was 4.2 months; in patients treated with intrathecal liposomal cytarabine, the median survival was 4.6 months, and in patients who did not receive intrathecal treatment, the median survival was 3.7 months (P = .717). Median survival after whole-brain radiotherapy was 4.6 months and with no radiotherapy, it was 3.2 months (P = .028). Multivariate analysis revealed a Karnofsky performance status (KPS) of > 70. Systemic intravenous/oral treatment and bone as a site of metastasis were factors prolonging survival from LM. CONCLUSION: Among treatment methods, only systemic therapy prolonged survival in patients with LM. Neither radiotherapy nor lumbar intrathecal therapy influenced survival in those patients; however, both methods alleviated signs and symptoms of LM. No difference in survival was observed in patients treated intrathecally with methotrexate and those treated with liposomal cytarabine. Treatment with both drugs was comparable.

Carcinomatous meningitis in a patient with metastatic breast cancer.

Metastases are defined as the appearance of neoplasms in parts of the body remote from the site of the primary tumor. Metastasis can occur through one of three processes: direct seeding of body cavities or surfaces, lymphatic spread, and hematogenous spread. The importance of laboratory utilization in the diagnosis of metastasis is explored using a case study of a 39-year-old female with metastatic breast carcinoma to the brain. This case study was carried out using clinical records, laboratory results, pathology reports, and physician interviews. Cerebrospinal fluid was obtained and examined in hematology, chemistry, and microbiology. Tissue from the breast was examined both before and after chemotherapy. Morphologic comparisons of both primary and metastatic tumor cells were carried out. The breast tissue showed infiltrating mammary carcinoma, ductal type, with 8/11 auxiliary lymph nodes showing metastasis. Evaluations of cerebrospinal fluid cell count results revealed the presence of malignant cells in remarkable numbers. Based on cytological and hematological results, a diagnosis of meningeal carcinomatosis was determined and treatment was started. Following the intrathecal chemotherapy, serial cerebrospinal fluid examinations showed the percentage of malignant cells decreased and no cells were detected 11 days after treatment. Metastasis, including meningeal carcinomatosis is a common occurrence with breast carcinoma. An effective chemotherapeutic treatment is evaluated for this disease when an accurate diagnosis is made. As demonstrated by this case study, proper use of the laboratory can help establish the diagnosis of metastasis.

Detection of tumor-derived DNA in cerebrospinal fluid.

The sensitivity of PCR-based methods for the detection of DNA offers opportunities for tumor diagnosis from the small amounts of tumor-derived DNA released into body fluids. We report the detection of tumor DNA in the cerebrospinal fluid (CSF) of two patients with intracranial neoplasms. One patient had a metastatic breast carcinoma which contained amplified HER-2/neu genes, and amplified HER-2/neu gene sequences were present in her CSF. The other patient had a glioblastoma which contained amplified epidermal growth factor receptor (EGFR) genes, and amplified EGFR gene sequences were present in her CSF. This report demonstrates that CSF sometimes contains tumor-derived DNA and suggests that PCR examination of CSF DNA may be diagnostically useful.