Melanoma is a form of skin cancer that develops from pigment-producing cells (melanocytes) and can become aggressive, spreading through the body. When melanoma cells travel from the original site to establish new tumors in distant organs or tissues, the disease is termed metastatic melanoma (stage IV disease). This spread typically occurs through the lymphatic system or the bloodstream, leading to secondary growths far from the primary tumor. The symptoms experienced by a patient depend entirely on the specific location where the cancer has traveled and the organs it has begun to affect. Understanding these potential signs is important for individuals who have received a melanoma diagnosis, as prompt recognition of changes can inform timely therapeutic decisions.
Generalized Symptoms of Widespread Disease
Cancer that has spread throughout the body often triggers non-specific systemic reactions indicating advanced disease progression. One of the most frequently reported symptoms is profound, persistent fatigue (malaise), which does not improve with rest. This exhaustion is thought to be related to the body’s ongoing inflammatory response and the increased metabolic demands of the growing tumors. Another common sign is unexplained weight loss, defined as losing ten pounds or more without intentional dieting or physical activity changes. This reduction is frequently accompanied by a noticeable loss of appetite (anorexia). Patients may also experience a persistent low-grade fever or drenching night sweats, reactions to cancer cells releasing substances into the bloodstream.
Signs of Visceral Organ Involvement
Melanoma frequently metastasizes to internal organs, and symptoms are linked to the functional disruption of the affected system.
Lungs
The lungs are one of the most common sites for distant spread, and involvement here can manifest as a persistent cough that does not resolve. Patients may also experience shortness of breath (dyspnea), which occurs as tumors restrict the lung’s capacity to exchange oxygen. In some instances, the tumors can cause irritation leading to chest pain or the coughing up of blood, known as hemoptysis.
Liver
Spread to the liver can cause symptoms related to its diminished function in processing waste and filtering blood. Patients may notice discomfort or pain in the upper-right quadrant of the abdomen. As tumors interfere with bile ducts, a patient may develop jaundice (yellowing of the skin and eyes). Loss of appetite and swelling in the abdomen, known as ascites, from fluid buildup are also indications of hepatic involvement.
Skeletal System
When melanoma reaches the skeletal system, it can cause significant, persistent, and worsening bone pain, sometimes without relief from typical medication. The presence of tumors within the bone can weaken the structure, leading to unexplained fractures from minor trauma or stress. In some cases, the breakdown of bone tissue releases excessive calcium into the blood, resulting in a condition called hypercalcemia.
Symptoms of Hypercalcemia
- Extreme thirst
- Frequent urination
- Confusion
- Abdominal pain
Neurological Manifestations of Metastasis
Metastasis to the central nervous system (CNS), including the brain and spinal cord, is a serious complication of advanced melanoma. Symptoms are often severe, resulting from tumors creating pressure within the skull or spinal column. Severe or persistent headaches are a frequent complaint, sometimes worsening in the morning or when a person bends over. The presence of tumor lesions can disrupt normal electrical activity in the brain, leading to seizures. Patients may also experience changes in vision, such as blurriness, double vision, or loss of peripheral sight. Cognitive changes are also common, presenting as memory problems, confusion, or altered personality traits. Depending on the brain region affected, patients may notice difficulties with balance or walking (ataxia), or develop weakness and numbness in the limbs. Due to the unique nature of melanoma cells, brain metastases have a higher tendency to bleed compared to other cancers, which can lead to a sudden onset of severe neurological deficits requiring immediate intervention.
Monitoring Local Recurrence and Urgent Medical Consultation
Individuals previously treated for melanoma must maintain vigilance for signs of local recurrence or regional spread, often manifesting on or under the skin. Local recurrence is defined as the reappearance of melanoma within a few centimeters of the original surgical scar. Spread can also occur through the lymphatic channels between the primary site and the closest lymph node basin. These regional metastases can appear as new lumps or firm nodules under the skin (satellite or in-transit metastases), which may be painless initially. Swelling or hardness in the lymph nodes (neck, armpit, or groin) can indicate spread to the regional lymphatic system. Any new lump, discoloration, or area of firmness in a previously treated region must be reported to the oncology team. Any new, persistent, or worsening symptom, whether systemic or localized to an organ, should trigger immediate consultation with a medical professional. The appearance of symptoms like a severe headache, an unexplained seizure, or sudden breathing difficulty constitutes a medical emergency. Reporting these changes promptly allows the healthcare team to perform diagnostic imaging and adjust the management plan to address the evolving nature of the disease.