This particular study didn't find a link ... are there any that did (and controlled for other carcinogenic activities like smoking tobacco)?
Probably some government studies. So I won't waste my time looking them up for you.
But, let's have some fun and guess.
On the one side we have tobacco, linked to cancer. Then we have homegrown marijuana with 50% more carcinogens than tobacco, 4X the tar, unfiltered smoke drawn deep into the lungs and held there, smoked allllll the way down to the last crud-filled molecule ... I don't know. Whaddya think? Think maybe there might also be a link to cancer?
It took decades of cigarette smoking by millions of Americans before the links between tobacco and lung cancer and other lung diseases were shown.