Metastatic squamous cell carcinoma in cerebrospinal fluid: why a rare diagnosis on cytology?

BACKGROUND: Squamous cell carcinoma metastatic to cerebrospinal fluid (CSF) is a rare diagnosis on cytology, and thereby more challenging in comparison to an adenocarcinoma metastatic to CSF. We recently encountered a case of metastatic squamous cell carcinoma in CSF. The primary site was unknown. A review of the literature was performed to understand why this is a rare diagnosis in cytology. CASE: A 56-year-old male was diagnosed with a keratinizing squamous cell carcinoma involving multiple lymph nodes in the neck. On extensive clinical and radiologic evaluation, a primary could not be identified. Subsequently, the patient presented with sudden loss of vision (in the right eye), nausea and vomiting. MRIs of the lumbar spine and optic nerve were suggestive of leptomeningeal and perineural seeding, respectively. Cytologic evaluation of CSF revealed a few atypical, round hyperchromatic cells which were confirmed as epithelial cells through immunocytochemistry for a broad-spectrum keratin. The diagnosis of metastatic carcinoma consistent with squamous cell carcinoma was rendered. CONCLUSION: Definitive diagnosis of metastatic squamous cell carcinoma is challenging unless clinical evidence is present. Besides other factors, the mode of spread to CSF may be responsible for this less common diagnosis.

[Retrospective study of a series of 26 carcinomatous meningitis secondary to lung cancer]. / Etude rétrospective d'une série de 26 cas de méningite carcinomateuse secondaire à un cancer bronchique.

Carcinomatous meningitis occur in approximately 5 to 18% of bronchial carcinoma. We report here the analysis of a retrospective study of 26 cases of carcinomatous meningitis secondary to a bronchial carcinoma. The most frequently involved histological types are adenocarcinoma and small cell lung cancer. The diagnosis is difficult because of the clinical polymorphism and the inconstant presence of neoplasic cells in the cerebrospinal fluid. The prognosis is very poor with a median survival time of 4 weeks. Development of new molecules as well as an earlier diagnosis could contribute to improve the outcome.

Failure of dithiothreitol and pronase to reveal a false-positive cryptococcal antigen determination in cerebrospinal fluid.

A patient with squamous cell carcinoma of the lung and a serum rheumatoid factor (RF) of 1:1,280 had a positive cerebrospinal fluid (CSF) latex agglutination test (LAT) for cryptococcal antigen, in culture-negative, India-ink-negative CSF. Pretreatment of the sample of CSF with 2-mercaptoethanol (2-ME) ablated the antigen titer and established the presence of a false-positive LAT, whereas CSF pretreated with dithiothreitol (DTT) and pronase continued to yield a false-positive result. The differing ability of pronase, DTT, and 2-ME to eliminate interfering substances from CSF has not been previously described. Moreover, because RF is unlikely to cross the blood-brain barrier, the authors postulated that malignant disease was responsible for the patient's false-positive LAT in CSF. Hence, the authors report the case to emphasize that false-positive LAT results in CSF are unlikely to be produced by RF and to underscore the benefit of using enzymatic and sulfhydryl-reducing agents when the validity of the initial test results are in doubt. Such a procedure will optimize the chances of accurately identifying false-positive LAT results in CSF.

[An autopsy case of primary intracranial squamous cell carcinoma].

An autopsied case of primary intracranial squamous cell carcinoma (PISCC) is reported, and 25 previously reported cases of PISCC, followed by the Garcia's criteria, are reviewed. A 72-year-old female was admitted to our service with chief complaints of headache and nausea on March 30, 1988. She had no neurological deficits on admission. However, CT examination revealed a round mass lesion in the left hypothalamus with dislocation of the brain stem. The cerebrospinal fluid (CSF) examination showed squamous cell carcinoma cytologically, and slightly higher levels of beta-HCG (13.0 ng/ml) and CEA (14.2 ng/ml). Because of progressive worsening in the level of her consciousness, total removal of a suprasellar tumor was performed on April 19, 1988. Gross appearance of the tumor was yellowish, soft and encapsulated. Histologically, it was squamous cell carcinoma. She did well for several days after the operation, then deteriorated. Finally she expired because of dissemination of the carcinoma on May 14, 1988. Postmortem examination revealed a large mass of squamous cell carcinoma in her right cerebellopontine angle. Except for that in the brain, no cancer was found in her body. Immunohistological study of the tumor specimen demonstrated positive for HCG in some of the large-sized neoplastic cells. Twenty-six cases of PISCC have been reported previously, so far. However, 21 cases out of the 26 PISCC were thought to have originated from intracranial epidermoid, one from the dermoid and the other one from craniopharyngioma. In the other three cases of PISCC, including the present case, the origin of the tumor was not able to be identified.(ABSTRACT TRUNCATED AT 250 WORDS)

Meningeal metastasis of squamous-cell carcinoma of the uterine cervix: case report and review of the literature.

Cervical squamous carcinoma metastatic to the central nervous system is an uncommon occurrence. Only eight such cases are reported in the literature. This is a case report of such a metastasis with emphasis on the cytologic features seen in the tumor cells found in the spinal fluid, along with a review of the literature.

Primary intracranial epidermoid carcinoma.

The cytologic findings in the cerebrospinal fluid in a case of primary intracranial epidermoid carcinoma are presented. The presence of a few squamous cells showing hyaline cytoplasm compatible with keratinization suggested the possible nature of the tomographically observed lesion. These tumors may arise in congenital epidermoid cysts at the base of the brain. Because of their location and meningeal spread, such tumors may cause severe symptoms and death despite a minute size, as illustrated by this case.