"Recently, a survey performed on 200 patients who were using medicinal cannabis during the first months after its introduction in the Netherlands was published.49 The survey showed that most of the respondents had previous experiences with cannabis use for medicinal purposes or with synthetic cannabinoids such as dronabinol, whereas a minority of 40% were “new” users. Most patients were satisfied using medicinal cannabis; only 10% of patients reported moderate to more severe transitory adverse effects. In about half of the users, the patients themselves took the initiative to suggest medicinal cannabis to their treating physicians as a therapeutic option, whereas in about 30% of users the initiative was taken by the involved general practitioner or medical specialist. In the remaining 20% of users, it was a joint initiative of both patient and clinician."

Source

de Jong, Floris A.; Engels, Frederike K.; Mathijssen, Ron H.J.; Zuylen, Lia van; and Verweij, Jaap, "Medicinal Cannabis in Oncology Practice: Still a Bridge Too Far?," Journal of Clinical Oncology (Alexandria, VA: American Society of Clinical Oncology, May 2005) Vol. 23, No. 13, p. 2889.
https://www.ncbi.nlm.nih.gov/…
http://ascopubs.org/doi/full/…