I agree… the journal is a bit of a complex math problem to try and piece together. In certain places the mOS chart is too overlapping to distinguish.
I analyzed the other 2 charts (MGMT methylated -unmethylated) looking for additional censored ticks. I found 2 additional censored ticks in the section between 19 - 20 month and one additional in the section between 24 – 26 month.
Conclusion : I count 30 censored ticks between 18 and 23.1 month and 37 censored ticks between 23.1 and 36 month. 30 + 37 = 67.