Meningeal carcinomatosis in patients with breast carcinoma. Clinical features, prognostic factors, and results of a high-dose intrathecal methotrexate regimen.

BACKGROUND

This retrospective study evaluates the results of a regimen of high-dose intrathecal methotrexate and the prognostic factors for the response in patients with meningeal from breast carcinoma.

METHODS

From 1979 to 1994, 68 breast carcinoma patients were diagnosed with meningeal carcinomatosis at a mean age of 52 years. All but two had previous metastatic involvement. The proportion of lobular and ductal carcinomas was balanced. Malignant cells were present in cerebrospinal fluid (CSF) samples from 61 patients, whereas the 7 remaining patients had increased CSF protein associated with computerized tomographic scan evidence of meningeal metastases. From 1989, 41 of the patients received a regimen of high-dose intrathecal methotrexate with systemic folinic acid rescue (HD-MTX+FA): intrathecal MTX, 15 mg daily x 5 days, repeated every 2 weeks, and intrathecal hydrocortisone acetate, 125 mg on Day 1, and folinic acid, 10 mg intramuscularly 12 hours after each MTX injection. Systemic treatment and radiation therapy were usually associated. Patients treated before 1988 received intrathecal MTX in conventional doses (15 mg once a week).

RESULTS

Clinical objective response, defined as a neurological improvement for at least one month, was achieved in 17 patients (41%) and stabilization in 14 (34%) treated with the HD-MTX+FA regimen. The response rate was significantly higher compared with that of the group treated with the conventional doses (P = 0.03). Median survival was 14 weeks for patients treated with the HD-MTX+FA regimen, compared with 7 weeks for patients who received conventional doses of MTX (P = 0.01). Grade 3 or 4 neutropenia was the main toxicity that occurred in 16 16 patients (39%) treated with the HD-MTX+FA regimen, and in 7 patients (33%) treated with conventional doses of MTX. In a univariate analysis, three parameters were singled out as having a favorable prognostic value for response to therapy; controlled systemic disease at diagnosis (P < 0.05), low initial CSF protein level (P < 0.05), and concomitant systemic chemotherapy during intrathecal therapy (P < 0.02). Multivariate analysis was not performed because the sample size was too small.

CONCLUSIONS

Although this study was retrospective, the intrathecal HD-MTX+FA regimen appears to be a more efficient strategy than conventional doses of MTX to induce neurologic improvement and perhaps better survival. It should be recommended in combination with systemic chemotherapy for selected patients with meningeal carcinomatosis from breast carcinoma who are likely to benefit from intensive therapy, i.e., patients with a CSF protein level less than 5 g/L and in whom systemic disease has been controlled.