Cancer Symptoms

Medically Reviewed by Poonam Sachdev on January 02, 2024
6 min read

No matter your age or health, it’s good to know the possible signs and symptoms of cancer. Although they aren’t enough to diagnose the disease, they can be clues for you and your doctor and help find and treat any problem as soon as possible. Cancer treatment works best early on when a tumor is small and hasn’t spread.

These symptoms don’t always mean cancer. In fact, the cause is usually something less worrisome, because lots of common conditions have the same symptoms. It’s important to see your doctor so they can take a closer look at your health and you can take action if needed.

Common early signs and symptoms of cancer in both men and women include:

  • Pain. Bone cancer often hurts 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 see a doctor if you don't know why it’s happening or if it doesn’t go away.
  • Weight loss without trying. Almost half of people who have cancer lose weight. It’s often one of the signs that they notice first.
  • 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 lasts more than 3 days, call your doctor. Some blood cancers, such as lymphoma, cause a fever for days or even weeks.
  • Changes in your skin. Have your doctor look at unusual or new moles, bumps, or marks on your body to be sure skin cancer isn’t lurking. Your skin can also provide clues to other kinds of cancers. If you notice skin changes such as darkening, a yellow or red hue, itching, increased hair growth, or an unexplained rash, it could be a sign of liver, ovarian, or kidney cancer or lymphoma.
  • Sores that don’t heal. Spots that bleed and won’t go away are also signs of skin cancer. Oral cancer can start as sores in your mouth. If you smoke, chew tobacco, or drink a lot of alcohol, you’re at higher risk.
  • Cough or hoarseness that doesn’t go away. A cough is one sign of lung cancer, and hoarseness may mean cancer of your voice box (larynx) or thyroid gland.
  • Unusual bleeding. Cancer can make blood show up where it shouldn’t be. Blood in your poop can be a symptom of colon or rectal cancer. Also, tumors along your urinary tract can cause blood in your urine.
  • Anemia. This is when your body doesn’t have enough red blood cells, which are made in your bone marrow. Cancers such as leukemia, lymphoma, and multiple myeloma can damage your marrow. Tumors that spread there from other places might crowd out regular red blood cells.

The most common cancers in men are prostate, lung, and colorectal.

Symptoms of cancer in men include:

  • Trouble peeing: A swollen prostate can make it hard to pee, or it may result in frequent urination. Tell your doctor if you have pain when you pee or blood in your urine.
  • A lump, pain, or ache in your scrotum. This might mean testicular cancer.

The types that affect women most are breast, lung, and colorectal cancers. Women can also have cancer of the uterus, endometrium, cervix, vagina, or vulva.

Watch out for:

Vaginal bleeding or discharge: Get checked out if it happens between periods or after menopause. Endometrial cancer, which develops in the lining of the uterus, 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 can cause indigestion or nausea. Cancer isn’t the only illness that changes your appetite, but check with your doctor if you’ve had trouble eating for 2 weeks or longer.

Belly pain and bloating: In most cases, you feel gassy, crampy, and bloated because of something minor. Talk to your doctor if you have these types of symptoms that 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.

If you have any possible cancer symptoms, you should let your doctor know. Depending on your symptoms and your health history, the doctor may order some tests to find out if cancer or another health problem is the cause.

To diagnose cancer, doctors might use blood tests and imaging tests such as CT scans and biopsies, in which tissue, cells, or fluid are taken from your body and examined under a microscope.

Even if you have no symptoms, it's important to see your health care providers regularly and to get any cancer screening tests recommended for you. These are tests that can catch cancer before any symptoms start, giving you the best chance for successful treatment.

Depending on your age, health history, family history, and sex assigned at birth, you might get screening tests for cancers of the breast, cervix, colon and rectum, or lungs. Some people at high risk for certain cancers may be offered added screening tests.

But keep in mind that even if you've had all the screening tests recommended for you, you could still develop cancer. You should still talk to your doctor about any new or worsening symptoms that could signal cancer or another health problem.

How long can you have cancer without knowing?

There's no simple answer, as there are many forms of cancer, and many factors influence how quickly any cancer grows and spreads enough to cause symptoms. But it is possible to have cancer for years without knowing it. For example, tumors of the colon and rectum usually grow slowly, starting out as growths called polyps. 

Which cancers are hard to detect?

Some cancers are hard to detect because there's no reliable screening test and they tend to grow and spread to an advanced stage before causing symptoms. These include cancers of the pancreas, brain, and ovaries.

Which is the easiest cancer to detect?

Skin cancers are one of the easiest ones to find, for an obvious reason -- you can see them growing on your skin. A dermatologist can tell you whether a new or changing mole or other growth on your skin is cause for concern. If the doctor thinks a growth could be cancer, they'll remove it and have it tested in a lab. That's the only way to know for sure.

What are the first signs of cancer?

The first signs depend on the type of cancer. The first sign of breast cancer might be a painless lump in the breast. A nagging cough might be the first sign of lung cancer. A sore inside your mouth could be a sign of oral cancer. But all of those symptoms have other possible causes as well.

What are the top causes of cancer?

In the U.S., scientists have ranked the top five preventable causes in this order: cigarette smoking, excess body weight, drinking alcohol, ultraviolet radiation exposure (mostly from the sun and tanning beds), and physical inactivity. Other preventable causes include diets low in fruits and vegetables or high in processed meat, and infection with the human papillomavirus (HPV). About 4 in 10 cancers are caused by such preventable factors. Other risk factors for cancer are things you can't change, such as your age or your genes. It's important to keep in mind that doctors still don't know why one person develops cancer and another doesn't, even if they have similar backgrounds or lifestyles.