Radiotherapy versus observation following surgical resection of atypical meningioma (the ROAM trial).

Kaur et al 1 have produced a timely systematic review on the role of adjuvant radiotherapy for atypical meningioma (AM) and malignant meningioma. Their review highlights the paucity of good quality prospective studies and the urgent need for prospective clinical trials for AM. Kaur et al 1 identify extent of resection (EOR) as an important prognostic factor but fail to comment on how this was defined. In 1957 Simpson 2 described a classification system that is still used today. The Simpson classification predates CT and MRI and is based upon the neurosurgeon ′ s assessment. Recently, several authors have questioned the use of Simpson grading in modern neurosurgery as a prognostic factor for risk of tumor recurrence, 3 instead proposing a change that defines EOR as either gross total resection (GTR) or subtotal resection (STR). In a recent review paper, GTR was described as Simpson 1 – 3, that is, no residual solid tumor, while STR equated to Simpson 4 – 5. 4 These definitions have been endorsed by both the European Organisation for Research and Treatment of Cancer (EORTC) and the Radiation Therapy Oncology Group (RTOG), and most prospective clinical trials for meningioma adopt this definition. The latest World Health Organization classification 5 has led to increased reporting of AM, 6 – 8 and there continues to be a marked institutional variation in patient management, particularly the use of early adjuvant radiotherapy. 9,10 Despite me-ningiomas being considered relatively radioresistant, radiotherapy remains the only available adjuvant therapy for these tumors in routine clinical practice. The role of early adju-vant radiotherapy for patients with AM who undergo a GTR, however, remains to be defined, 1 leading to a lack of class I evidence. 11 Of these retrospective studies, patient numbers in the radiotherapy and observation arms are frequently unequal, and the relatively short median time to recurrence emphasizes the nonbenign nature of these tumors. Moreover, the treatment decision (ie, adjuvant radiotherapy vs no adjuvant radio-therapy) after surgery is likely to depend on the patient ′ s pretreatment characteristics. As in any retrospective analysis, there are differences in known and unknown prognostic factors , which may be associated with patient outcome. As such, the assessment of the radiotherapy effect in these studies suffers from bias caused by confounding by indication. 12 One further major limitation of all these studies is the lack of data on health-related quality of life. Kaur et al …