12 Potential Signs of Cancer (& What To Do)

Updated in October 2023

Cancer in any part of the body can cause expected symptoms like weight loss (even if you are not actively partaking in a weight loss diet or exercising intensely), fatigue and persistent pain. However, to confirm a diagnosis, several tests will need to be done to rule out other illnesses.

Normally, cancer is diagnosed with a patient presents with specific symptoms that can occur at any time of the day without a concrete explanation, Symptoms can also continue to emerge with another condition that was not adequately treated. This can occur, for example, when a gastric ulcer evolves to stomach cancer. 

If a patient presents with signs of symptoms that may suggest cancer, it is important for the doctor to complete a thorough assessment on the patient’s health status, taking their family history into consideration as well. This way, if cancer is determined, then treatment can start as early as possible, which can increase the probability of a cure. 

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Top signs of cancer

Symptoms that you should not ignore include:

1. Weight loss without dieting or exercise 

Rapid weight loss of up to 10% of your weight within 1 month without partaking in a diet or exercising intensely is a frequent symptoms of the development of cancer. This particularly happens with cancer that occurs in the pancreas, stomach or esophagus, but it can also happen with other types. 

2. Intense fatigue after simple tasks  

It is relatively common for people with a new cancer to present with anemia or loss of blood through the stool. This can lead to decreased red blood cells and a reduction of oxygen in the blood, causing extreme fatigue even after small tasks (like going up the stairs or making a bed). 

This fatigue can also occur with lung cancer if the tumor is affecting healthy cells and decreasing respiratory function. This type of fatigue gradually gets worse over time. In addition, people with more advanced cancers can also have fatigue in the morning, soon after waking, even if they slept well throughout the night. 

3. Persistent pain

Pain localized to a specific spot is common with various types of pain, like brain cancer, bone cancer, ovarian cancer, testicular cancer or intestinal cancer. In most cases, this pain does not improve with rest and it is not caused be intense exrcise or other illnesses (like arthritis or a muscular injury). This type of pain is constant and does not decrease with cold or warm compresses. It usually only improves with strong analgesics. 

4. Fever that comes and goes without taking medication 

An irregular fever can be the sign of cancer, like leukemia or lymphoma. It often emerges when the immune system has been weakened. Generally, fever emerges for a few days, and then disappears without having to take any medication. It then returns and continues to be unstable, without the accompaniment of any symptoms like it happens with the flu. 

5. Stool changes

Having intestinal changes, like very hard stool or diarrhea that lasts for more than.6 months, can be a sign of cancer. In addition, some cases of cancer, it is also common to have significant changes to stool habits, like having constipation that lasts for days alternating with diarrhea that lasts for days, very swollen abdomen, blood in the stool, nausea and vomiting. 

This variation in stool habits is usually persistent and is not related to factors like food intake or other intestinal illnesses (like irritable bowel syndrome). 

6. Pain with urination or dark urine

Patients with a new cancer may have pain with urination, urine with blood, or urinary frequency. These are the most common symptoms in cancers that occur in the bladder or prostate. This symptoms can also be a sign of a urinary tract infection, however, and therefore an infection should be ruled out before confirming a cancer diagnosis.

7. Prolonged healing time of wounds 

Wounds can emerge in any part of the body, like the mouth, skin or vagina, for example. However, if they take longer than 1 month to heal, this can be a sign of a cancer in its early stages. It means that the immune system is weakened and that there are a decreased amount of platelets available to help with healing. In the meantime, this delay also occurs with diabetics, and can be a sign of uncontrolled diabetes. 

8. Bleeding

Bleeding can also be a sign of cancer that emerges in the early or advances stages. Patients may notice blood when coughing, in the stool, in the urine or from nipple, depending on where the cancer is growing. 

Vaginal bleeding unrelated to menstruation, dark discharge, urinary frequency or menstrual cramps can also be a sign of cancer. 

9. Skin spots 

Cancer can cause skin changes, like bruising, yellow skin, red spots, purple pinpoints or dry skin that itches. 

In addition, color, shape or size changes to moles, freckles or wrinkles can also be a sign of skin cancer or another type of cancer. 

10. Lumps or swollen lymph nodes

Swollen lymph nodes or lumps can appear in any region of the body, like in the breast or testicles. In addition, bloating or swelling of the abdomen can occur, due to an increase in liver size, as well as swelling in the armpits, groin and neck.

11. Frequent choking 

Some patients with cancer may have difficulty swallowing, resulting in choking and persistent coughs. This particularly happens with cancers in the stomach, esophagus or pharynx. 

Swollen lymph nodes in the neck, increased abdominal volume, bruising and bone pain are symptoms associated with leukemia. 

12. Hoarseness and coughing that lasts for over 3 weeks 

Having a persistent cough, shortness of breath and a hoarse voice can be a sign of cancer in the lungs, larynx or thyroid. The presence of a persistent dry cough, accompanied by back pain and intense fatigue can be a sign of lung cancer. 

Other symptoms that can indicate breast cancer are changes to breast size, redness, crusting or wounds close to the nipples, or nipple discharge.  

What to do if you suspect cancer  

If you suspect cancer, you should go to your doctor to complete blood testing, like PSA and CEA, which are tumor markers in the blood that will increase in the presence of cancer. 

In addition, the doctor may order an ultrasound or MRI to observe any affected organs, and in some cases, more imaging or a biopsy are required. 

Though lab testing and imaging, the doctor is able to identify the type of cancer and determine the severity. They can see whether the cancer has metastasized and what the response to treatment may be. 

Being aware of signs and symptoms 

It is important to monitor for signs of symptoms of cancer and to see your doctor if you suspect you have any. Treatment for cancer is much more efficient when cancer is diagnosed in its early stages, and it is less likely to spread to other parts of the body, increasing the chances of a cure.  

There are no signs of symptoms that you should ignore, especially if they persist for more than 1 month. 

Treatment options 

After the cancer is diagnosed, the doctor will indicate the state of the tumor and the treatment options available. Treatment can vary depending on the age of the patient and the type of cancer present. Options include: 


Surgery may be completed to remove the whole tumor, parts of it, or just other tissue that may have been affected by it. This type of treatment is indicated for tumors that occur with colon cancer, breast cancer and prostate cancer, as these areas are the easiest to operate. .


This involves the exposure of ionized radiation to the tumor to decrease its size. It can be prescribed before or after surgery.

The patient will not feel anything during treatment, however side effects may occur following radiation, like nausea, vomiting, diarrhea, and red or sensitive skin. These usually last for a few days. Rest is important when recovering from radiation. 


Sometimes referred to as just chemo, chemotherapy is characterized by the administration of a cocktail of medication. It can be taken as pills, injections or injections, administered at the hospital or at a treatment center. 

Chemotherapy can consist of just one medication or it can be a combination of medications to be taken as pills or injectables. Side effects of chemotherapy can include anemia, hair loss, nausea, vomiting, diarrhea, mouth ulcers or fertility changes. Prolonged chemotherapy, however, can lead to leukemia (a type of blood cancer), however this is very rare.  


These are medications that can make the body able to recognize cancerous cells, making it able to combat the cancer more efficiently. The majority of immunotherapy treatments are injectable and act throughout the body. It can cause symptoms, however, like allergic reactions, itching, fever, headache, muscular pain or nausea. 

Hormone therapy 

These are medications that serve to combat hormones that are associated with tumor growth. Side effects of hormone therapy depend on the medication used, but they can include impotence, menstrual changes, infertility, breast sensitivity, nausea, headache or vomiting. 

Bone marrow transplant 

This option is used for blood cancers, like leukemia. It aims to replace cancerous bone marrow with healthy bone marrow. Before the transplant, the patient will receive high doses of chemo or radiation to destroy cancerous cells and normal bone marrow cells, so that they can receive the transplanted bone marrow from a compatible match. Side effects of this treatment include infections, anemia, or rejection of the transplanted bone marrow.