I've been having intermittent right shoulder pain (ache) for 4 months now. I do have mid-upper back pain which my chiropractor has told me I keep sublaxing. I'm 23, 195 (was 226 June 3rd until I started exercising and eating healthy) and ever since I lost 30 pounds my back problems have cleared up immensely, but sometimes do randomly act up. My biggest issue has just been the shoulder ache. Should I be highly concerned about lung cancer?