• Basics of Cancer
• Tumor Biology
• Common Risk Factors
• Clinical Staging
• Clinical Presentation
• Diagnosis
• Treatments of Cancer
• Comparison of Cancer Treatment
• Prevention

Cancer patients can exhibit both that are either disease-specific or disease non-specific. Disease-specific symptoms relate to one specific disease and can be used as clues in diagnosis. The symptoms are mostly caused by the compression upon organs due to the overly growth of the tumors. Some of the generalized symptoms occur when substances produced during the growth of tumors enter into the blood circulation. For example, the steroid-like excretions into the body of lung cancer patients may affect the calcium level within the blood, resulting in neural and muscular malfunctions, causing fatigue and dizziness.

1. Non-disease-specific symptoms

• Weight Loss: Occurs in most patients
• Fever: Occurs in almost every type of tumors. It is sometimes due to infections with an weakened immune system during cancer therapies.
• Fatigue: attributed to multiple factors, including physiological, psychological and environmental, etc. Most patients have fevers.
• Pain: Mainly due to compression from the tumor.
• Discoloration of the skin: deepened complexion, pigmentation, reddening, rashes, itches, and hair-overgrowth.

• Bowel movement and changes in urination pattern: chronic constipation, diarrhea, changes in stool shape may indicate colon cancer. Dysuria, bloody urine and malfunction of bladder may indicate tumors in bladder or prostate.
• Intractable pain: persistent oral pain may indicate oral cancer.
• Unusual hemorrhage and excretion: Blood in sputum can be a symptom of lung cancer. Occult blood in defecate indicates colorectal cancer. Endometrium or cervical hemorrhage may indicate endometrial cancer. Bloody urine is a symptom of bladder or kidney cancer. Bloody excretion of nipples may indicates breast cancer.
• Lumps in breast or other locations: Tumors in breasts, testicles, lymph nodes and other soft tissues often present as mass or lumps noticeable by touch.
• Indigestion and dysphagia: These symptoms indicate stomach cancer, esophageal cancer and nasopharyngeal cancer.
• Warts or distinct change in birth mark, etc.: If these skin marks show signs of discoloration, blurring margin, or significant enlargement, malignancies such as melanoma may exist.
• Persistent coughs and hoarseness: intractable coughs may be symptoms of lung cancer, as hoarseness may be the symptom of pharyngeal or thyroid cancer. Often times, appearance of such symptoms indicates cancers at late stages.

Different presentations of benign and malignant tumors

	Benign Tumors	Malignant Tumors
Local symptoms	Slow growth, smooth surface, clear margin, movable by touch, symptoms related to compression.	Fast growth, expansion in a short period of time, uneven surface, unclear margin. Other than obstruction and compression, the tumor affects functions of the organ and creates necrotic ulcer, which leads to infections (e.g. acute hemotysis in stomach patients)
Generalized symptoms	Normally, no generalized symptom, except for tumors in the endocrine system. Not life-threatening except those in vital organs such as the brain	Generalized symptoms present. Weight loss, fever and loss of appetite appear in early stages. Late stage patient has anemia and is often under a state called cahexia, which often causes death if not treated in time

3. Other presentations

• Paraneoplastic syndrome:Paraneoplastic syndrome is a group of symptoms caused by biologically active excretions secreted by tumorous tissues. These symptoms include: itches, dermatitis, pulmonary oriented osteohypertrophy, peripheral neuritis, migratory thrombosis venous infection, glucocorticoid hyperplasia, chronic anemia, leukmoid reactions, etc.
  
• Cahexia: Cahexia is characterized by anorexia, malnutrition, anemia, electrolyte disturbance, decrease in blood protein and signs of weakness, which may cause distortion of human internal metabolism and death.