Abstract
A late-onset treatment-related changes (TRCs), which represent radiographic radiation necrosis (RN), frequently occur after stereotactic radiosurgery (SRS) for brain metastases and often need surgical treatment. This study aimed to validate the true pathology and investigate clinical implication of surgically resected TRCs on advanced magnetic resonance imaging (MRI). Retrospective analyses of 86 patients who underwent surgical resection after radiosurgery of brain metastases were performed. Fifty-four patients displayed TRCs on preoperative MRI, comprising pure RN in 19 patients (TRC-RN group) and mixed viable tumor cells in 35 patients (TRC-PD group). Thirty-two patients revealed the consistent diagnosis of progressive disease in both MRI and histopathology (PD–PD group). The TRC-PD group showed larger prescription isodose volume (9.4 cm3) than the TRC-RN (4.06 cm3, p = 0.014) group and a shorter time interval from SRS to preoperative MRI diagnosis (median 4.07 months) than the PD–PD group (median 8.77 months, p = 0.004). Progression-free survival was significantly different among the three groups (p < 0.001), but not between TRC-RN and TRC-PD (post hoc test, p = 1.00), while no difference was observed in overall survival (p = 0.067). Brain metastases featured as TRCs after SRS frequently contained viable tumor cells. However, this histologic heterogeneity had a minor impact on benign local prognosis of TRCs after surgical resection.
Highlights
A late-onset treatment-related changes (TRCs), which represent radiographic radiation necrosis (RN), frequently occur after stereotactic radiosurgery (SRS) for brain metastases and often need surgical treatment
As no patient who was diagnosed as progressive disease (PD) in preoperative magnetic resonance imaging (MRI) and RN in histologic diagnosis after surgical resection, patients were classified into three groups in final analyses; TRC-RN, TRC-PD, and PD–PD groups
We investigated the clinical implication of TRC-PD representing patients with discrepant radiopathology and surgical histopathology
Summary
A late-onset treatment-related changes (TRCs), which represent radiographic radiation necrosis (RN), frequently occur after stereotactic radiosurgery (SRS) for brain metastases and often need surgical treatment. This study aimed to validate the true pathology and investigate clinical implication of surgically resected TRCs on advanced magnetic resonance imaging (MRI). Brain metastases featured as TRCs after SRS frequently contained viable tumor cells. This histologic heterogeneity had a minor impact on benign local prognosis of TRCs after surgical resection. Current guidelines for management of brain metastases (BM) include stereotactic radiosurgery (SRS) or radiotherapy as a key modality for local control with high efficacy[3,4,5]. Differentiating TRC from progressive disease (PD) has been a matter of debate for managing patients with TRC, because both present similar imaging appearance in conventional magnetic resonance imaging (MRI) of enlarged, heterogeneous rim enhancement in the T1-weighted s equence[6,7]. TRC has been variously classified according to the time after irradiation, and a pathological
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
