Clinical outcome and prognostic analysis of meningeal carcinomatosis treated by intrathecal chemotherapy

Refinement of intrathecal catheter design to enhance neuraxial distribution

BACKGROUND

Delivery of therapeutics via indwelling intrathecal catheters is highly efficacious for targeting of pain, spasticity, neuraxial cancer and neurodegenerative disorders. However, current catheter designs have some major limitations. Given limited CSF flow, fixed intrathecal volume and the large distance of the rostro-caudal spinal axis, current intrathecal delivery routes fail to achieve adequate drug distribution. Additionally open catheter systems are plagued with cellular ingrowth and debris accumulation if used intermittently.

NEW METHOD

RESULTS/COMPARISON WITH EXISTING METHOD(S): High speed imaging showed micro-valve catheters greatly increase fluid exit velocities compared to typical open-ended catheters, which prevents pooling of injectate proximal to the opening. When implanted intrathecally in rats, small injection volumes (7.5 μL) of dye or AAV9-RFP, resulted in an even rostro-caudal distribution along the spinal axis and robust transfection of neurons from cervical to lumbar dorsal root ganglia. In contrast, such injections with an open-ended catheter resulted in localized distribution and transfection proximal to the delivery site. Our poly micro-valve catheter design resulted in equivalent transfection rates of cervical DRG neurons using 100x lower titer of AAV9-RFP. Unlike open port catheters, no debris accumulation was observed in the lumen of implanted catheters, showing potential for long-term intermittent use.

CONCLUSIONS

This catheter platform, suitable for small animal models is easily scalable for human use and addresses many of the problems observed with common catheter systems.

Randomized Phase II Trial of Proton Craniospinal Irradiation Versus Photon Involved-Field Radiotherapy for Patients With Solid Tumor Leptomeningeal Metastasis

PURPOSE

Photon involved-field radiotherapy (IFRT) is the standard-of-care radiotherapy for patients with leptomeningeal metastasis (LM) from solid tumors. We tested whether proton craniospinal irradiation (pCSI) encompassing the entire CNS would result in superior CNS progression-free survival (PFS) compared with IFRT.

PATIENTS AND METHODS

We conducted a randomized, phase II trial of pCSI versus IFRT in patients with non-small-cell lung cancer and breast cancers with LM. We enrolled patients with other solid tumors to an exploratory pCSI group. For the randomized groups, patients were assigned (2:1), stratified by histology and systemic disease status, to pCSI or IFRT. The primary end point was CNS PFS. Secondary end points included overall survival (OS) and treatment-related adverse events (TAEs).

RESULTS

Between April 16, 2020, and October 11, 2021, 42 and 21 patients were randomly assigned to pCSI and IFRT, respectively. At planned interim analysis, a significant benefit in CNS PFS was observed with pCSI (median 7.5 months; 95% CI, 6.6 months to not reached) compared with IFRT (2.3 months; 95% CI, 1.2 to 5.8 months; P < .001). We also observed OS benefit with pCSI (9.9 months; 95% CI, 7.5 months to not reached) versus IFRT (6.0 months; 95% CI, 3.9 months to not reached; P = .029). There was no difference in the rate of grade 3 and 4 TAEs (P = .19). In the exploratory pCSI group, 35 patients enrolled, the median CNS PFS was 5.8 months (95% CI, 4.4 to 9.1 months) and OS was 6.6 months (95% CI, 5.4 to 11 months).

CONCLUSION

Compared with photon IFRT, we found pCSI improved CNS PFS and OS for patients with non-small-cell lung cancer and breast cancer with LM with no increase in serious TAEs.

Clinical efficacy and safety of different doses of intrathecal methotrexate in the treatment of leptomeningeal carcinomatosis: a prospective and single-arm study

OBJECTIVE

To investigate the clinical efficacy and safety of different doses of intrathecal methotrexate in the treatment of leptomeningeal carcinomatosis.

METHODS

53 patients admitted to the Second Hospital of Hebei Medical University with leptomeningeal carcinomatosis were recruited. They were divided into two groups: 15-mg-group received 15 mg methotrexate intrathecally, while the other received 10 mg methotrexate. All patients were followed up to 31 December 2020 or until death. Primary endpoint was the response rate. Secondary endpoints were survival and safety. Treatment-related adverse events were recorded.

RESULTS

The intrathecal chemotherapy was regularly maintained in 42 cases. Most primary cancers were lung (60.4%), stomach (18.9%) or breast (5.7%). The clinical response rate was higher in the 15 mg group than the 10 mg group (62.5 vs. 34.5%, P = 0.042). In the 15 mg group, two cases showed myelosuppression and one case showed seizures. In the 10 mg group, one patient appeared fever, three patients appeared myelosuppression and one showed leukoencephalopathy. However, there were no serious irreversible adverse reactions in neither of the two groups. In terms of survival, the median survival was 15.7 weeks in the 15 mg group and 27.1 weeks in the 10 mg group (P = 0.116). Multivariate analysis showed that only targeted therapy improved the survival (P < 0.0001, HR = 5.386).

CONCLUSION

Increased dose of methotrexate did not prolong the overall survival, but it was more effective in relieving clinical symptoms with no increased adverse reactions. Targeted therapy might improve the survival.

Classification of Leptomeningeal Metastases from Solid Organ Malignancies and Clinical Outcomes: Series from a Cancer Research Centre

Leptomeningeal metastases (LMs) are a critical neurological manifestation of solid organ malignancies. Early diagnosis and prompt treatment is necessary to improve outcomes. We classified LM on the basis of cytological or histological and imaging studies. A total of 14 patients of LM from solid organ malignancies diagnosed between July 2016 and December 2018 were included in the series. LM was classified based on cerebrospinal fluid (CSF) cytology and magnetic resonance imaging (MRI) findings. Survival outcomes were noted. LM from carcinoma of breast and lung accounted for most of the cases. Type I LM was seen in 12 patients while 2 accounted for type II LM. Median overall survival (OS) was 40.5 days. Newer-generation tyrosine kinase inhibitor (TKI) therapy seems promising in the treatment of LM. Classification of LM based on cytology/histology and imaging findings allows early diagnosis and treatment. Newer-generation TKIs should be used for the treatment of LM if indicated.

Management of leptomeningeal carcinomatosis and challenges of trial design

PURPOSE OF REVIEW

Highlight recent data in lung and breast cancer leptomeningeal disease and address clinical trials that are open for patients.

RECENT FINDINGS

Patients with lung and breast cancer leptomeningeal disease have survival outcomes of less than 1 year, despite advances in treatment strategy. Efforts to develop liquid biopsy biomarkers of disease progression from cerebrospinal fluid and plasma are underway. There are over 10 clinical trials open for patients with leptomeningeal disease, half of which use immunotherapy.

SUMMARY

Consortium-based, multicenter clinical trials for patients with leptomeningeal disease are urgently needed to expand the treatment armamentarium.

Seizure prevalence, contributing factors, and prognostic factors in patients with leptomeningeal disease

BACKGROUND

To determine seizure prevalence and contributing factors in patients with leptomeningeal disease (LMD).

METHODS

Authors performed a retrospective review of 79 consecutive patients with a diagnosis of LMD. Associations between categorical variables were assessed using Chi-Square tests or Fisher's Exact tests. Survival was plotted with Kaplan Meier curves. Variables with a log-rank p-value of <0.20 were entered into a Cox Proportional Hazard regression analysis.

RESULTS

Seizure prevalence in those with and without brain metastases was 22%. Of those who seized, 65% were admitted for this at least once while only one patient required intubation. Primary malignancy, type or route of chemotherapy administration, form of radiation therapy (craniospinal, focal, or whole brain), surgical treatment, location of LMD, and number of brain metastases did not influence seizure development. Only 13% of patients who never had seizures were on a prophylactic AED (anti-epileptic drug). In patients who had brain metastasis, there was no significant difference in prevalence of seizure before versus after LMD diagnosis suggesting that LMD does not significantly increase the risk of seizure compared to brain metastasis alone. A multivariate analysis revealed that while males trended toward inferior survival, only performance status and treatment with systemic chemotherapy showed a significant association with survival. Median survival time of patients after LMD diagnosis was four months.

CONCLUSION

The prevalence of seizure in LMD patients is 22%. There were no statistically significant predisposing factors to seizure development. ECOG and use of systemic chemotherapy were found to be significant prognostic factors.