Group Therapy and Cancer Survival-- Where Does the Evidence Lie in 2007?

One of the most hotly debated questions within oncology over the past decade has been whether the promotion of psychological wellness can extend survival for patients with advanced cancer.^1,2 The converse—that psychiatric disorder shortens survival—seems true, with mechanisms of poor self-care and reduced adherence to anticancer treatments resultant from depressive or psychotic disorders explaining this outcome.³

But can group therapy for patients with advanced cancer help to extend survival? Three carefully conducted and methodologically sound replication studies of supportive expressive group therapy (SEGT) for women with advanced breast cancer have been completed recently without evidence of extended survival.^4-6 Just as better studies examining whether stress is a cause of cancer suggest that it is not,⁷ so, too, it seems unlikely that promoting psychological wellness will extend survival. In reviewing these studies, let us take stock of the current status of the field of psycho-oncology and what the benefits of group therapy are in this setting.

Adjusting to a diagnosis of advanced breast cancer can be one of the most challenging and overwhelming tasks of a woman's life. SEGT, a professionally led psychosocial group intervention, provides a safe and supportive environment in which women can express their cancer-related concerns and overcome any feelings of isolation and stigma that so often accompany a cancer diagnosis.

The main goals of SEGT are summarized as building bonds, expressing emotions, "detoxifying" death and dying, redefining life's priorities, fortifying families and friends, enhancing doctor-patient relationships, and improving coping.⁸ In so doing, major emphasis is placed on the role of relationships in facilitating patients' adjustment to illness, including relationships within the group itself, with family and friends, and with treating clinicians.⁹

SEGT was initially developed by Yalom's group in the 1970s for women with metastatic breast cancer. Early reports were promising and indicated an effect on psychological distress and quality of life, including reducing symp- toms of depression and self-reported pain among women with metastatic cancer.^10,11

It was not until 1989, however, that interest in and research on SEGT began to truly flourish, spurred almost entirely by the publication of a 10-year follow-up of a randomized controlled trial (RCT) of women with advanced breast cancer. In this seminal paper, Spiegel and colleagues¹² reported that women who received SEGT survived an average of 18 months longer than controls, who received only routine care. This unexpected survival benefit generated widespread interest in the intervention and stimulated investigations aimed at replicating and extending these findings.

Illustrative of the scientific interest in SEGT and the ongoing debate that it inspires, Fox demonstrated that the survival of the control patients in the original cohort was markedly poorer than a San Francisco Surveillance, Epidemiology and End Results (SEER) program sample and argued that selection biases were the explanation for the 1989 Stanford findings.¹³

In response, Goodwin and colleagues argued that while results from the original trial may have indeed lacked external validity (ie, the ability to be generalized to other groups given the nonrepresentativeness of the sample), the study itself nevertheless possessed internal validity, the hallmark and goal of randomization and randomized clinical trials, and that as a result the impact of the intervention within the study population cannot be discounted.¹⁴

Although Fox has further countered some of Goodwin and colleagues' arguments, including questioning whether the original study was indeed internally valid,¹⁵ both sides agreed that additional studies are needed to cross-validate and replicate the earlier findings.

In the Canadian Breast Expressive-Supportive Therapy (BEST) multisite study of 235 women with advanced breast cancer, survival was unaltered for those receiving SEGT compared with controls (17.9 months and 17.6 months, respectively).⁴ In California, Spiegel's group enrolled 125 women in their replication study and also failed to identify a survival benefit (SEGT, 30.7 months; controls, 33.3 months).⁶ Finally, in Melbourne, survival was not significantly prolonged in an RCT of 227 women with advanced breast cancer (SEGT, 24.0 months; controls, 18.3 months).⁵ Taken together, these 3 studies provide strong, mounting evidence that SEGT does not extend patient survival.