gms | German Medical Science

Objective: Little is known about growth of glioblastoma. While meningiomas tend to grow proportionally slow, glioblastoma volume tends to explode in a short period of time. Since these tumours are highly aggressive, operative resection, if possible, should be planned shortly after diagnosis.

How long should a waiting period for glioblastoma resection be at most for optimal outcome?

Methods: In this retrospective, preliminary study the data of 102 patients were screened for diagnostic and pre-operative MRI-scans, which lay at least 7 days apart. Tumour volume was estimated in 27 cases. Diagnostic MRI-scans and pre-operative MRI-scans were compared. Volume was estimated using the BrainLab^© cranial planning tool (Smart Brush). Waiting time and tumour growth were estimated, as were means and standard deviations (SD).

Results: In 27 cases, patients waited longer than 7 days for surgery, the least waiting time was 8 days, at most patients waited for 63 days. Mean and SD of waiting time between diagnostic MRI and pre-operative MRI were 21,33 ± 12,75 days. The mean age was 64 ± 12 years. Sizes of the tumours ranged from 0,18 to 55,9 cm³ with a mean of 21,48 ± 16,12 cm³ in diagnostic scans and from 0,8 to 56,1 cm³ with a mean of 25,99 ± 17,92 cm³ in pre-operative scans. 23 tumours grew significantly while 3 shrunk. Mean absolute growth was 4,5 ± 7,59 cm³ (from -16,6 cm³ to 25,9 cm³), while relative growth was 97,65 ± 222,94 % (from -54,6 to 1111,1 %). Correlation is moderately high with 0,57 between waiting time and tumour growth.

Conclusion: Not only time seems to determine tumour growth, but also factors, which are not visible in MRI scans. That is why an operative resection of possible glioblastoma should be planned as soon as possible to prevent exponential growth, which leads to greater neurological damage and could make resection quite more difficult. Further studies should focus on patient’s outcome.