context: No matter your age or health, it's good to know possible signs and symptoms of cancer. By themselves, they aren't enough to diagnose the disease. But they can provide clues to you and your doctor so that you can find and treat it as soon as possible. Treatment works best when your cancer is still small and hasn't spread. Early treatment gives you a better shot at curing your cancer. To be clear: These symptoms don't always mean cancer. There are plenty of common ailments that can make you feel this way. That's why you go to the doctor -- to take to take a closer look at your health and take action. Pain: Bone cancer often hurt from the beginning. Some brain tumors cause headaches that last for days and don't get better with treatment. Pain can also be a late sign of cancer, so it's good to see a doctor if you don't know why you have it or it doesn't go away. Weight loss without trying: It's common to lose weight when you have cancer. It's often one of the signs of cancer that people notice first. Almost half the people with cancer lose weight by the time they get diagnosed. Fatigue: If you're tired all the time and rest doesn't help, tell your doctor. Leukemia often wears you out, or you could have blood loss from colon or stomach cancer. Cancer-related weight loss can leave you exhausted, too. Fever: If it's high or sticks around for more than 3 days, call your doctor. Some blood cancers, like lymphoma, cause a fever that lasts for days or even weeks. Changes in your skin: Get unusual or new moles, bumps, or marks on your body checked. You want to be sure skin cancer isn't lurking. Your skin can also provide clues to other kinds of cancers. If it's darkened, looks yellow or red, itches, sprouts more hair, or if you have an unexplained rash, let your doctor take a look. It could be a sign of liver, ovarian, or kidney cancer. Sores that don't heal: Spots that bleed and won't go away are also signs of skin cancer. If you're a smoker, chew tobacco, or drink a lot of alcohol, you're at higher risk of oral cancer. It sometimes starts as sores in your mouth. The three most common cancers in men are prostate, lung, and colorectal. Keep an eye out for: Cough or hoarseness that won't go away: See the doctor if a cough is severe, lasts more than 3 weeks, or you see blood when you cough. Trouble peeing: A swollen prostate can make it hard to go, or it may make you have to go a lot. Tell your doctor if you have pain when you pee or blood in your urine. Change in bowel habits. Diarrhea or constipation that lasts for more than 4 weeks can be a sign of colorectal cancer. Blood in your poop isn't normal. Tell your doctor. The types that affect women most are breast, lung, and colorectal cancer. Women can also have cancer of the uterus, endometrium, cervix, vagina, or vulva. Keep an eye out for: Bleeding or discharge: Get checked out if it happens between periods or after menopause. Endometrial cancer can make you bleed when you don't expect it. Changes in appetite: Ovarian cancer can make you feel full or make it hard to eat. Other cancers that only women get can cause indigestion or nausea. Cancer isn't the only illness that brings on changes in your appetite, but keep it in mind if you've had trouble eating for 2 weeks or longer. Belly pain and bloating: In most cases, feeling gassy, crampy, and bloated are not due to cancer, but check with your doctor if you are having these types of symptoms that persist and don't go away. Breast changes: Tell the doctor if: Your breasts feel different. You find lumps. You notice sudden changes in size. You have discharge from your nipples. You see spots or other changes in the skin around your nipples.