Will this increase my chances of getting into a good college?

Growing up I always worked for straight A’s. I’ve never gotten anything below a B. I’ve been studying for the SATs for 6 months and I will take them this April (so I’m confident I will get a good score) my problem is my extracirricular activities aren’t remarkable. For the end of middle school and first 2 1/2 years of high school my mom had gotten cancer and her husband (not my dad) travels a lot for work. So for those years I mostly stayed home helping her with my many brothers and sisters. I didn’t get to do much, but this past summer I put in 80 hours of volunteer work at a hospital and will do that agin next summer which should bring in my total to 200+ hours. Also I have been selected for this summer program and the university of Washington. It’s for kids who hope to become surgeons. They only allow 100 kids. That should look pretty good right? Does anyone think I have a disadvantage because of my lack of extracurriculars? Or will my volunteer work and summer program make up for that? My dream school is Johns Hopkins. I’ve wanted to go there ever since I was little. Also I’m a junior. Thanks

It’ll depend very much on your grades and SAT scores. Until we know those, chancing you properly is impossible.

Schools will definitely understand a situation like yours.

Taking care of a patient at home can be considered an EC.
http://www.studypoint.com/caf/extra-curricular-activities/