The CancerWeb Report, What's New In Cancer: January, 1997
Cancer in General

• Psychological stress and cancer, no relationship? - The perennial question of an association between cancer and stressful life events never seems to have a definitive answer. In many cases the stress studied and the symptoms used as indicators of psychological stress may be too generalized to give a definitive answer, while in other studies, insufficient allowance has been made for altered psychological state in response to developing cancer. It is clear that definitive answers demand very definitive questions, together with good study design. A report by the Danish Cancer Society, appearing in the January, 1997 issue of the British Journal of Cancer, examined the effect of a very definitive stress, cancer in a child, on the cancer incidence and non-cancer mortality in 11,231 parents. It covered the records of children who developed cancer between 1943 to 1985, and cancer and death among their parents up to 1992. There were 1665 cancers diagnosed and 2137 non-cancer related deaths among the parents, versus expected figures of 1702 and 2333, respectively, based on national rates. The data provided no support for an effect of even such a stressful experience, and testified to the resilience of humans even to extreme psychological stress. (Johansen, Br J Cancer 75:144, 1997)

  ---

• New approach to suicide gene' treatment of cancer - The idea of introducing into cancer cells a suicide gene' which converts an otherwise harmless pro-drug into a potent cell-killing agent only within the target cells, is an intriguing approach to gene therapy of cancer. The most-often used system is herpes simplex virus thymidine kinase and the pro-drug ganciclovir. However, the limitation is that ganciclovir only kills cells during the S-phase of their cell cycle in which only a small proportion of cells will be at any given time. A report from St. Thomas' Hospital, London, appearing in the December, 1996 issue of Gene Therapy, describes a promising alternative. These researchers used the nitroreductase B enzyme from the common gut bacterium Escherichia coli and a range of nitrogen-containing compounds on which the enzyme works. Using a V79 cell line, they found the best result with a compound code-named CB1954 with a 770-fold increase in cell kill when the gene had been inserted into the cells; there also was a 97-fold increase in cell kill with nitrofurazone, and 9- to 50-fold increase with other nitro compounds. While far from being ready for clinical use, the approach does point the way to great increases in the selectivity of previously poorly-selective chemotherapy drugs. (Bailey, Gene Ther 3:1143, 1996)

  ---

• Outpatient management is appropriate for patients treated with high-dose chemotherapy and stem cell rescue - At a time when hospital stays have been drastically reduced in length under primarily cost-motivated pressures, it is essential that there should be solid clinical data to back up early discharge or support more prolonged hospital stay when necessary. That is why a report in the January, 1997 issue of the Journal of Clinical Oncology is important. Clinicians at the Scripps Clinic in La Jolla, California, determined that outpatient management was both safe and acceptable for patients undergoing high-dose chemotherapy with autologous stem-cell support for both hematologic and solid cancers. This conclusion was reached in a study of 113 patients who underwent 165 treatment cycles. Initially, the patients were hospitalized for the chemotherapy and then maintained as outpatients, unless there were troublesome toxicities (STOT); later all treatment was on an outpatient basis (TOT). 85% of all patients were agreeable to the outpatient status, and length of hospital stay was reduced from 18.3 days to 8.2 (STOT) and 2.8 (TOT) days. (Meisenberg, J Clin Oncol 15:11, 1997)