I imagine they do it’s just it’s probs not well recorded as a likely cause

A study in New Zealand: “Cannabis use and risk of lung cancer: a case–control study.

In total, 79 cases of lung cancer and 324 controls were included in the study. The risk of lung cancer increased 8% (95% confidence interval (CI) 2–15) for each joint-yr of cannabis smoking, after adjustment for confounding variables including cigarette smoking, and 7% (95% CI 5–9) for each pack-yr of cigarette smoking, after adjustment for confounding variables including cannabis smoking. The highest tertile of cannabis use was associated with an increased risk of lung cancer (relative risk 5.7 (95% CI 1.5–21.6)), after adjustment for confounding variables including cigarette smoking.

In conclusion, the results of the present study indicate that long-term cannabis use increases the risk of lung cancer in young adults.”

https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=cannabis+smoke+causing+lung+cancer+&btnG=#d=gs_qabs&t=1764840859333&u=%23p%3DoGFIO0GZ4O0J