Comprehensive Review of Cancer-Related Diseases and Their Major Types

Abstract

Cancer represents a broad collection of disorders in which the normal mechanisms controlling cell growth, division and survival become disrupted. Genomic alterations, epigenetic changes and external influences can allow abnormal cells to multiply beyond normal limits. With progression, malignant cells may infiltrate neighbouring tissues and travel to distant organs through metastasis. Important biological features include resistance to programmed cell death, persistent stimulation of blood-vessel formation, genomic instability and reduced recognition by the immune system. The occurrence of cancer differs according to age, sex, geographical region and socioeconomic conditions, making it a major worldwide cause of illness and death. Developments in molecular biology have clarified the roles of oncogenes, tumour-suppressor genes and cellular signalling pathways. These advances have supported more selective treatments and the growth of personalized oncology. Current management may include surgery, radiation, chemotherapy, targeted medicines and immunotherapy. Nevertheless, tumour heterogeneity, treatment resistance and the difficulty of preventing cancer at population level remain important challenges. Continued research is therefore required to improve prevention, diagnosis and treatment outcomes.