Due to the availability of effective systemic therapies and closer surveillance during follow-up, the number of patients diagnosed with recurrent BM is increasing [1–4]. However, the inevitable question of how to treat these patients adequately after cerebral progression still remains unsolved, especially for patients maintaining a good clinical condition over a longer period of time before BM recurrence . Most studies with respect to treatment of recurrent BM focus on a single treatment option such as (re-) radiosurgery or re-irradiation .
Surgery is well established as a first-line treatment for larger and symptomatic BM. However, the role of surgery for pretreated, recurrent BM is not yet defined, and only scarce data, originating from the pre-molecular era, are available. Only a few studies have reported on the feasibility of (re-)surgery in patients with single or multiple recurrent BM [8, 9, 13, 14]. They included narrowly defined patient cohorts previously treated by either surgery [8, 15] or sRS [14, 16], and reported median survival rates after resection of between 7.5 and 11.5 months. With 11.1 months the survival rate in the present study was within the range of the previously reported data.
The high rate of fatal cerebral progression in this series compared to previous studies may be due to the fact that besides surgery, most therapeutic options are used, leading to a lack of salvage treatment in the case of further cerebral progression. As surgical resection may result in rapid symptom release by reducing the mass effect, the subsequent improvement in the patient’s clinical condition, possibly in combination with a re-evaluation of the tumor’s molecular status, may represent the major benefit of surgery. Since a fair clinical status is a prerequisite for radio-oncological and a tailored adjuvant treatment, this may positively influence the outcome, as observed before . However, this benefit could not be observed with statistical significance for the patients in the present study.
Probably, the specific condition of this study’s population offers an explanation since it comprises patients who had already undergone extensive oncological treatment. Possible subsequent development of resistance may leave few remaining therapeutic approaches.
In cases of extensive pretreatment by radiotherapy, resection might therefore be the only local treatment option left. As the cerebral progression partly reflects treatment failure of previous irradiation, the negligible impact of postoperative radiotherapeutic measures on either EFS or OS in this present study is not surprising.
The major argument for surgery in this patient cohort may be seen in the clinical improvement which is, in line with the current literature, the strongest predictor for further survival after recurrent BM treatment [4, 8, 16].
As opposed to the clinical improvement mentioned above, the postoperative complication rate was high and included a critical number of life-threatening complications. This is in contrast to other studies reporting on resection in the setting of initial BM diagnosis, where neurosurgery was usually well tolerated and proved to be feasible and safe [8, 14–16, 18, 19].
The high incidence of complications may be explained by the general condition of oncological patients. The underlying malignancy and/or multiple varied (systemic) pre-treatments would impair wound healing and hemostasis, and increase cardio-pulmonary complications [4, 20]. Furthermore, patient age was described as independently correlating with clinical outcome, since comorbidities are more common in elderly patients [4, 21, 22]. In this context, the indication for re-resection of BM must be based upon multidisciplinary consent that takes into account the patients´ general condition, the possible (and probable) clinical benefit, and the availability of further treatments.