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This article, published in the journal Cytopathology, discusses the diagnosis of myelomatous meningitis through cerebrospinal fluid cytology examination. Myelomatous meningitis is a rare complication of multiple myeloma, a neoplastic plasma cell disorder. The article presents a case study of a 72-year-old woman with a history of IgA-lambda multiple myeloma who developed symptoms of headache, disequilibrium, and neurological deficits. Cerebrospinal fluid analysis, combined with immunocytochemistry, confirmed the presence of myeloma cells in the central nervous system, leading to a diagnosis of myelomatous meningitis. The article emphasizes the importance of prompt diagnosis and multidisciplinary approaches in managing this condition. [Extracted from the article]

Lidong Jiao,1 Min Wei,1 Yongjuan Fu2 1Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, People’s Republic of China; 2Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, People’s Republic of ChinaCorrespondence: Lidong Jiao Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 ChangChun Street, XiCheng District, Beijing, 100053, People’s Republic of China Tel +86-10-83198814 Email jlddr2021@163.comObjective: To explore the disease manifestations and radiological characteristics of patients with meningeal carcinomatosis (MC) combined with myelopathy.Patients and Methods: The detailed medical information of patients who suffered from MC with myelopathy in record system were collected and reviewed.Results: In these patients, five cases were male and two cases were female. The age was from fifteen to fifty-seven years. In the course of disease, tumor cells were discovered in cerebrospinal fluid of three patients and in biopsy samples of four patients. Cerebrospinal fluid (CSF) test results showed white blood cell counts increased in seven patients, protein increased in six patients and glucose reduced in five patients. In addition, MRI revealed that the white matter abnormalities showed in all cases and pia mater was enhanced in four patients, meningeal enhanced was observed in three patients. All patients were given appropriate therapy during hospitalization. Follow-up result showed that all patients passed away two to five months after diagnosis.Conclusion: MC causes spinal membrane, spinal nerve root to be involved besides, also can produce the matter of myelopathy. Early detection of intramedullary lesion is conducive to strengthening the awareness of the diagnosis of MC.Keywords: meningeal carcinomatosis, myelopathy, histopathological investigation, CSF cytology

Introduction: Leptomeningeal carcinomatosis (LC) is diagnosed in 4-15% of cancer patients, and most cases (70%) are in the advanced phase of the disease. In only 5-10% of patients with LC, it is the initial manifestation of cancer. Case report: We present a case of a 46-year-old man with leptomeningeal carcinomatosis as the first manifestation of type B highgrade lymphoma. Cerebrospinal fluid (CSF) showed pleocytosis with a predominance of mononuclear cells, hyperproteinorrhachia, and glucose consumption. CSF cytology was negative for malignant cells in two samples. Magnetic resonance imaging and CSF flow cytometry gave the diagnosis. Discussion: LC is a diagnostic challenge. Differential diagnosis arises with infectious processes (tuberculosis) and autoimmune diseases. In cerebrospinal fluid, flow cytometry (FCM) has a higher sensitivity than cytology for the diagnosis of LC. [ABSTRACT FROM AUTHOR]

Medulloblastoma Ependymoma Atypical teratoid/rhabdoid tumour Ganglioneuroblastoma Which of the following represents the typical immunochemical profile of this tumour? Cerebrospinal fluid, CSF cytology, atypical teratoid rhabdoid tumour, brain tumour, cytology, rhabdoid tumour Keywords: atypical teratoid rhabdoid tumour; brain tumour; cerebrospinal fluid; CSF cytology; cytology; rhabdoid tumour EN atypical teratoid rhabdoid tumour brain tumour cerebrospinal fluid CSF cytology cytology rhabdoid tumour 153 156 4 12/22/21 20220101 NES 220101 An atypical teratoid rhabdoid tumour (AT/RT) is an extremely rare malignant neoplasm. [Extracted from the article]

Lymphomatosis cerebri (LC) and cauda equina lymphoma are both rare forms of primary central nervous system lymphoma (PCNSL). LC is characterized by diffuse bilateral non-enhancing (or partially enhancing) inltrative lesions without mass effect, which can be easily confused with other forms of leukoencephalopathy and, thus, lead to delays in diagnosis. For the first time, a case of LC concomitant with cauda equina involvement confirmed by brain stereotactic biopsy is presented. This case highlights the necessity of using a multimodal strategy in diagnosing PCNSL, including multimodal magnetic resonance, cerebral spinal fluid cytology, flow cytometry and fluorodeoxyglucose positron emission tomography/computed tomography. [ABSTRACT FROM AUTHOR]

Abstract Background Primary central nervous system lymphoma (PCNSL) is the most prevalent brain, spinal cord, eyes, and leptomeningeal lymphoma. It is often misdiagnosed due to an unspecific presentation or unavailable biopsy and results in a poor prognosis. Although the craniocerebral imaging examination of PCNSL has some characteristics, it is limited, and atypical cases are especially difficult to identify with intracranial tumours and other diseases. The biopsy, as the gold standard for PCNSL diagnosis, is not eligible for all patients suspected of having PCNSL. Case presentation This report documents a woman who presented with a three-month history of numbness and weakness in the right leg. She was treated with drugs at a local hospital for one month. She developed demyelination lesions and her symptoms were aggravated. The patient was admitted to the Department of Nerve Infection and Immunology at Tiantan Hospital. Head magnetic resonance imaging (MRI) enhanced scanning indicated significant inflammatory demyelinating disease, and lymphoma was not excluded. CSF revealed a high protein level and CSF cytology detected abnormal cells, PCNSL was eventually presumed according to positive CSF cytology and cytological detection of the cerebrospinal fluid flow. Conclusions PCNSL is a highly invasive tumour. With the development of technologies such as cerebrospinal fluid cytology and flow cytology, CSF analysis has become one of the definite diagnosis methods, and the tumour cell finding in CSF is the only reliable basis for diagnosis. Flow cytometric analysis and gene rearrangement testing also provide objective evidence.

Abstract Background Cerebrospinal fluid (CSF) analysis is a crucial method in the diagnostic process for suspected subarachnoid hemorrhage (SAH), especially when cerebral imaging is negative or inconclusive. CSF cytology (detection of erythrophages or siderophages) is used to determine whether a bloodstained CSF resembles a genuine SAH. Whether erythrophages may develop in vitro after a traumatic puncture in case of delayed CSF analysis is unclear. An in vitro development of erythrophages after traumatic puncture would diminish the diagnostic properties of CSF analysis. We assessed whether erythrophagocytosis is detectable in CSF after an imitated traumatic lumbar puncture. Methods We mimicked a traumatic lumbar puncture by mixing surplus CSF with whole blood from the same patient. From this mixture, cytological specimens were obtained immediately and repeatedly at time intervals of 1 h, until 7 h after mixing, or until the mixture was exhausted. Each cytological specimen was microscopically examined independently by four experienced CSF cytologists for the presence of erythrophages. Results We studied 401 CSF cytological specimens of 96 punctures in 90 patients. We could not identify any erythrophages in all cytological specimens. Fleiss’ Kappa for interrater-reliability was 1.0. Conclusions We did not find evidence for an in vitro erythrophagocytosis after a mimicked traumatic lumbar puncture. Therefore, the occurrence of erythrophages in CSF cytology can be regarded as a reliable sign of an autochthonous bleeding in the subarachnoid space. Our results support the crucial role of CSF analysis in clinical practice in case of a suspected SAH but negative cerebral imaging.

Mollaret's meningitis refers to the classical description by Pierre Mollaret of recurrent episodes of fever and meningism lasting 2-5 days, followed by spontaneous recovery. It remains a rare entity and most often is attributed to reactivation of latent Herpes Simplex virus (HSV)-2 virus. Though considered self-limiting and innocuous, there are exceptional cases in which neurological sequelae have been reported. From a clinician's perspective, narrowing down the diagnosis may not be straightforward and would require judicious use of investigations. Here we report two cases of Mollaret's meningitis, both of whom had negative cerebrospinal fluid (CSF) polymerase chain reaction (PCR) for HSV. These reports also highlight an unusual pattern of presentation of this rare entity and the utility of CSF cytology in clinching the diagnosis. [ABSTRACT FROM AUTHOR]

Primary central nervous system lymphoma (PCNSL) is a very rare tumor of increasing incidence. It is often misdiagnosed due to the unspecific presentation or unavailable biopsy, and results in poor prognosis. PCNSL involved the spinal cord is extremely sparse. Here we report a gentleman presented with one-year history of progressive tremor in the left limbs and slight dysarthria as well as three-month history of paraparesis, tinnitus and insomnia. MR images disclosed the swollen cerebellum and cauda equine, with contrast enhancement in both meninges and nerve roots. The cerebrospinal fluid (CSF) revealed extremely high protein level. Tubercular meningitis was considered and anti-tuberculosis therapy was given for weeks but without relief. With progressive deterioration, the PCNSL was eventually presumed according to positive CSF cytology and exclusion of systemic involvement. However, the patient passed away within days. We then reviewed the current diagnostic methods of PCNSL. The biopsy, as the gold standard for PCNSL diagnosis, is not eligible for all patients suspected PCNSL. The presurgical diagnostic algorithm of PCNSL has been fixed by clinicians and we suggest the early and repeated CSF cytology should be included for definitive diagnosis. [ABSTRACT FROM AUTHOR]

Melanoma is the most frequent solid tumor associated with leptomeningeal metastasis (LM). The usual diagnostic tools, that is, cytomorphological assessment of cerebro-spinal fluid (CSF) and gadolinium-enhanced MRI of the entire neuraxis both lack effectiveness. The CellSearch Veridex technology for the detection of circulating tumor cells (CTC) in blood was designed for the follow-up and prognosis of breast, prostate, colorectal, and lung cancer, which express EpCAM markers. We have previously adapted this technology to detect malignant cells in the CSF of breast cancer LM. Our objective here was to check if this technology would also allow the detection and the enumeration of CTC in the CSF of melanoma patients presenting with LM although melanoma does not express EpCAM markers. On the occasion of the intrathecal treatment of LM in 2 melanoma patients, 5 mL of CSF and 7.5 mL of blood were collected on CellSave Preservative Tubes and analyzed within 3 days after CSF sampling using a melanoma-dedicated kit. The CellSearch Veridex technology was then adapted to direct enrichment, enumeration, and visualization of melanoma cells in the CSF. CD146+, HMW-MAA+, CD34−, and CD45− cells with typical morphology could be observed and enumerated sequentially with reproducible results, corresponding to CSF melanoma cells (CSFMC). In contrast to the current gold standard cytomorphological analysis, this new approach allowed a precise quantification of CSFMC in all samples concomitantly analyzed. This methodology, established on a limited volume of sample and allowing delayed processing, could prove of great interest in the diagnosis and follow-up of melanoma patients with LM. [ABSTRACT FROM AUTHOR]

Background: The diagnosis of leptomeningeal metastasis (LM) in patients with solid tumors remains difficult. The usual diagnostic methods of cytomorphological assessment of cerebro-spinal fluid (CSF) and gadolinium enhanced MRI of the entire neuraxis lack both specificity and sensitivity. The Veridex CellSearchW technology has been designed for the detection of circulating tumor cells (CTC) in blood from cancer patients and validated for the follow-up and prognosis of breast, prostate, colorectal, and lung cancer. Our aim was to adapt this technology for the detection and the enumeration of tumor cells in the CSF of breast cancer patients presenting with LM. Methods: On the occasion of a randomized phase III study evaluating the role of the intrathecal treatment in LM from breast cancer (DEPOSEIN, EudraCT N°: 2010-023134-23), the CellSearchW technology was adapted to direct enrichment, enumeration and visualization of tumor cells in 5 mL CSF samples, collected on CellSaveW Preservative Tubes and analyzed within 3 days after CSF sampling. Results: Sixteen CSF of 8 patients with primary breast cancer presenting with LM were studied. EpCAM+/cytokeratin + cells with typical morphology could be observed and enumerated sequentially with reproducible results in low or elevated numbers in 8 patients. Conclusion: This methodology, established on a limited volume of sample and allowing delayed processing, could prove of great interest in the diagnosis and follow-up of cancer patients with LM, especially to appreciatethe efficacy of chemotherapy. [ABSTRACT FROM AUTHOR]

It is not known whether the HER2 status of malignant CSF cells coincides with that of the original breast carcinoma cells. We investigated whether CSF cytology specimens were suitable to evaluate HER2 status by fluorescence in situ hybridization (FISH) in patient with leptomeningeal metastasis (LM). Both formalin-fixed paraffin-embedded (FFPE) breast cancer tissue and liquid based CSF cytology specimens were evaluated for HER2 status in 16 patients with LM. We evaluated HER2 gene amplification using FISH on destained CSF cytology slides containing a minimum of 20 malignant cells per slide, and compared these with the HER2 status by immunohistochemistry (IHC) or FISH in FFPE tissues. HER2 was considered positive when the HER2:CEP17 ratio was ≥2.0 or IHC 3+. Of 16 cases, four were HER2 positive and 12 were HER2 negative by FISH analysis in CSF cytology. All CSF-positive cases were HER2 positive by IHC in FFPE tissue. Of 12 HER2 FISH-negative cases in CSF cytology, 10 were HER2 negative (IHC 0 or 1+) and two were IHC 2+ in FFPE tissue. Two IHC 2+ cases had HER2:CEP17 ratios of 1.27 and 2.1, respectively, by FISH in FFPE tissue. As a result, the HER2 status concordance rate between metastatic breast cancer cells in CSF and FFPE primary tissue by IHC and FISH was very high. When CSF cytology specimens were appropriately prepared and had adequate cellularity without dry artifacts, the CSF cytology was suitable to evaluate HER2 status by FISH analysis in patients with LM. [ABSTRACT FROM AUTHOR]

Abstract: Acute leukemia presenting with central nervous system (CNS) signs and symptoms is uncommon and prone to be misdiagnosed. Here, we report nine patients with acute leukemia, including five patients with acute lymphoblastic leukemia (ALL) and four patients with acute myeloid leukemia (AML). These patients presented with symptoms suggestive of involvement of multiple cranial nerves, the spinal cord, and meningeal involvement. Moreover, we found that all these patients unexpectedly showed the presence of blasts in the cerebrospinal fluid (CSF) but not in the peripheral blood despite repeated examinations. Bone marrow examination confirmed the presence of acute leukemia in these patients. Seven patients died within 18months of diagnosis and two patients developed stable disease. Our findings show a novel presenting feature of acute leukemia and highlight the importance of CSF cytology in the diagnosis of acute leukemia. [ABSTRACT FROM AUTHOR]

Neoplastic meningitis is a diffuse dissemination of tumour cells in the cerebrospinal fluid (CSF), leptomeninges, or both. It occurs in approximately 5-10% of malignant diseases, most often in breast cancer, lung cancer, melanoma, and B-cell lymphoma. Symptoms of neoplastic meningitis include head or back pain, cranial nerve palsies, diffuse radicular symptoms, and psychiatric disturbances. Magnetic resonance imaging shows nodular contrast enhancement lining the CSF spaces. Positive CSF cytology requires optimal sampling and processing, and the treatment of neoplastic meningitis must be individualized. The CSF dissemination can be treated with intrathecal chemotherapy with methotrexate or Ara-C. Radiotherapy should be applied only to symptomatic solid spinal manifestations or fast progressing cranial nerve palsies. Systemic chemotherapy is needed to control solid manifestations or, in the case of substances entering the CSF, to support intrathecal chemotherapy. [ABSTRACT FROM AUTHOR]

Copyright of Der Onkologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archiv für Psychiatrie und Nervenkrankheiten is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archiv für Psychiatrie und Nervenkrankheiten is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archiv für Psychiatrie und Nervenkrankheiten is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A 43-year-old man died from the complications of astrocytoma metastasis. He first noticed symptoms of a lumbar disc prolapse in 1979. In 1987 a pilocytic astrocytoma (grade I) of the spinal cauda was removed. In 1989 a tumor recidivation at the same site was partially removed. Histology showed a grade II astrocytoma. Two months later the patient developed symptoms of increased intracerebral pressure. CSF cytology showed polymorphic giant tumor cells with hyperchromatic nuclei and a glioblastoma of the cerebral ventricles was diagnosed. The patient died from cardiovascular complications. The post-mortem investigation revealed an astrocytoma of the conus medullaris with an anaplastic ventral area (grade IV). This area was inaccessible to the biopsy. It is believed that tumor metastases from anaplastic parts spread along the spinal cord and brainstem and finally invaded the brain and cerebral ventricles. [ABSTRACT FROM AUTHOR]

This paper reviews the diagnostic role of monoclonal antibody immunohistochemistry in a series of 189 brain tumour biopsies and 22 cases of neoplastic meningitis. The diagnostic monoclonal antibody panel, which includes markers for glial, neural, epithelial and lymphoid differentiation antigens, was used to test a wide variety of cerebral and spinal tumours by indirect immunofluorescence and immunoperoxidase techniques on unfixed frozen sections. Gliomas, meningiomas, schwannomas, medulloblastomas, choroid plexus tumours, cerebral lymphomas and metastatic carcinomas could all be reliably differentiated by means of their characterisctic antigenics profiles, as defined by their patterns of reactivity with the antibody panel. Confident diagnosis was possible even in very poorly differentiated tumours and in biopsies distorted by surgical squeeze artefact, where paucity of morphological clues made diagnosis by conventional histological methods difficult or impossible. It was estimated that use of the antibody panel was responsible for, or made a significant contribution towards the final diagnosis in approximately 20% of cases. The monoclonal reagents were also found to be of great value in the detection and characterisation of neoplastic cells in CSF specimens from patients with malignant meningitis. Malignant cells were detected in 73% of cases and characterised in 16% of cases by routine cytological techniques. Employing monoclonal immunocytology however, these figures were improved to 95% and 95% respectively. Our findings suggest that patients with neoplastic meningtitis can be spared prolonged investigation and inappropriate management by the early detection and characterisation of malignant cells in CSF using panels of monoclonal antibodies. [ABSTRACT FROM AUTHOR]

Copyright of Archiv für Psychiatrie und Nervenkrankheiten is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Medulloblastoma is one of the commonest primary CNS malignancies in children. Leptomeningeal dissemination and distant metastasis have been associated with medulloblastoma, but intramedullary metastases are very rare. CSF cytology and contrast-enhanced MRI are the main modalities used to diagnose leptomeningeal dissemination. However, intramedullary metastases are best picked up with contrast-enhanced axial sequences on MR imaging. In this report, a patient with medulloblastoma who developed intramedullary metastasis is described. The role of imaging and CSF cytology in diagnosing the spread along the CSF pathways is reviewed. Allusions are made to the possible mechanism of intramedullary metastasis in these tumors. [ABSTRACT FROM AUTHOR]

Cerebrospinal fluid (CSF) evaluation for total and differential cell count is a common practice in pathology for evaluation of various disease conditions. Although rare, these CSF samples yield interesting and unusual morphological findings, which are not only of academic interest, but also may play key roles in diagnosis. For diagnosing metastatic carcinoma in brain and meninges, CSF examination is one of the important tools along with imaging studies. Metaplastic breast carcinoma (MBC) encompasses a rare (<1% of all breast cancers), aggressive and highly heterogeneous group of tumors. MBC is almost always estrogen receptor, progesterone receptor and Her2 negative (triple negative) and shows frequent early distant metastases as well as sub-optimal response to systemic therapies. The involvement of leptomeninges is most commonly associated with these triple- negative subtypes. In this report, we present an unusual case of malignant cells with prominent intracytoplasmic granules in CSF smears of a 46-year-old female with metastatic MBC with acinar differentiation. An extensive review of literature in English language did not return any other reports of a similar finding., (© 2020 Wiley Periodicals LLC.)