Cross-sectional observational studies reveal that cancer is more prevalent in depressed persons. Psychosocial stressors such as depression, anxiety, stressful life events, poverty, and lack of social support may favor carcinogenesis. Cancer acquired under these circumstances has a poor prognosis. Conversely, when cancer has developed in the presence of these factors, effective management or treatment of these psychosocial stressors may bring about increased survival time of the affected persons. The purpose of this narrative literature review is to examine the role that maladaptive stress responses play in cancer initiation and progression. Relevant databases, hand searches and authorative texts were critically analysed and the findings were integrated. Stress is influenced by genetic, environmental, pharmacological, and infectious factors in addition to the chronicity of depression, social isolation, and poor stress-coping capacity. Chronic psychosocial stress-induced maladaptive activation of the neuroendocrine system may dysregulate immunoinflammatory responses, alter oncogene expression, promote tumor-related angiogenesis, and accelerate growth of cancer with stimulation of neuroendocrine activity, which may favor cancer progression. The evidence that associates psychosocial stressors to cancer progression is stronger than the evidence which links the same psychosocial stressors to cancer incidence.