Cancer is serious business.

Heavy.  Cruel.  Vicious.  When the patient is a young person, the prospect of cancer seems even worse.  But most people with cancer, and their friends and families, are capable of enjoying moments of happiness and laughter.  Joseph Gordon-Levitt brings the full sad-to-happy spectrum of emotions in his excellent portrayal of a 27-year-old with a tumor on his spine.

This movie’s title “50/50” refers to Joseph Gordon-Levitt’s character’s chance of surviving his cancer.  It is also the approximate ratio of grim content to light content in the film.

Seth Rogen, as Gordon-Levitt’s best friend, provides the movie’s biggest laughs, many coming from his crude sexual advice.  Gordon-Levitt’s reaction to the pot-laced baked goods he consumes during chemotherapy scores some hearty chuckles as well. The funny business in “50/50” is more than just comic relief, it’s a major part of the movie.

Anna Kendrick plays Gordon-Levitt’s rookie therapist whose counsel he regards lightly during early visits.  Her suggestions are met with relative indifference, but she keeps plugging away.  Kendrick delivers a strong performance.  Angelica Huston plays Gordon-Levitt’s mom and Bryce Dallas Howard is Gordon-Levitt’s girlfriend.

Should a person going through cancer treatment see this movie?  If she or he has a good sense of humor and is not in great pain, the answer is yes.  If she or he is depressed and/or physically uncomfortable, stay away.  For the cancer-free public, your feelings about this movie will, I think, parallel your general feelings about Seth Rogen.

“50/50” is rated R for raunchy.