In a substantial study of three thousand breast cancer patients, all of whom were nurses, completed in 2006, researchers found that women without close friends had a mortality rate of four times that of women with a close circle of friends.
In another study of 514 women, 239 were diagnosed with breast cancer. One of the results of this study was that those with the least social support were nine times as likely to develop cancer following a stressful life event. In fact, most psychooncology studies have found a positive correlation between survival time after cancer diagnosis and the amount and quality of social support.
Price M, Tennant C, and Butow P. The role of psychosocial factors in the development of breast carcinoma: Part II: Life event stressors, social support, defense style, and emotional control and their interactions. Cancer, 2001;91(4):686-697.
Waxler-Morrison N, Hislop T, Meares B, and Kan L. Effects of social relationships on survival for women with breast cancer: a prospective study. Society for Science in Medicine, 1991;33:177-183.
Maunsell E, Brisson J, and Deschenes L. Social support and survival among women with breast cancer. Cancer, 1995;76:631-637.
Brown J, Butow P, Culjak G, Coates A, and Dunn S. Psychosocial predictors of outcome: Time to relapse and survival in patients with early stage melanoma. Brittish J of Cancer, 2000;83:1448-1453.