Reirradiation for recurrent primary central nervous system tumors: Eight-year audit from a tertiary cancer care center in South India.

BACKGROUND

Radiation therapy is a major treatment option in the management of primary central nervous system (CNS) tumors, though recurrences after primary treatment, especially in high-grade glial tumors, is a challenge for treating physician. Advances in the field of radiation have made reirradiation a feasible option in recurrent CNS tumors.

MATERIALS AND METHODS

Details of patients with primary CNS lesions who presented between 2009 and 2016, with recurrent CNS lesions, and who were treated with reirradiation were retrieved from electronic medical records, as a departmental audit, and the outcome was analyzed.

RESULTS

A total of 33 patients received reirradiation. Median follow-up was 112.7 months. Median age at presentation was 36 years. On completing initial treatment, 42.4% had no residual disease. Median time to symptomatic recurrence was 51.33 months. For reirradiation, stereotactic radiotherapy was used in 27.3%, stereotactic radiosurgery in 12.1%, and intensity-modulated radiation therapy in 36.4%. Mean cumulative 2 Gy equivalent dose (EQD2) was 111.00 ± 15.287 Gy. At the last follow-up, 57.6% of patients were alive, and 27.3% had succumbed to the disease. Median OS was 187.67 months. Three-year survival after reirradiation was 74.1%.

CONCLUSION

Our study is probably one of the first from the Indian subcontinent analyzing a series of reirradiation in primary CNS tumors. Our survival subsequent to reirradiation is comparable to that in available literature; which are also mostly retrospective. Our analysis also substantiates that younger patients, longer intervals between the two sets of radiation and biologically effective dose <100 Gy and EQD2of <100 Gy are factors that favorably improve the survival after reirradiation as has been shown in literature.