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Notes: Abstract Cancer of the colon and rectum is numerically the most major of visceral cancers in both sexes. A great proportion of colorectal cancer patients die of local problems. This report deals with the various techniques used to manage local recurrence, lung and liver metastases, and the control of pain.

Notes: Summary In order to evaluate a self-reading system for the measurement of immunocompetence in cancer prognosis, a battery of delayed-type hypersensitivity skin tests with antigens including dermatophytin, candida, Varidase (streptokinase-streptodornase), mumps, and purified protein derivative (PPD) was administered to 50 cancer patients. The resulting erythema and induration were read by both technicians and patients at 24 and 48 h after placement of the tests. In addition, another group of 85 cancer patients received two identical candida skin tests placed at the same time on either the same or the opposite arm. The results from these two groups of patients indicated that patients' readings correlated well with technicians' readings, with most of the correlation coefficients being greater than 0.8. The weakest correlations were with antigens producing a large response. There was significant variability in the two identical simultaneously placed skin tests, and the correlation coefficients were much lower. The relevance of these data to serial skin testing is discussed.

Notes: Summary In an attempt improve the response to BCG or BCG + DTIC therapy in Stage IIIB melanoma patients, we added thymosin treatment with repeated doses of 4 mg/m2 or 40 mg/m2. Twenty-eight patients were clinically and immunologically evaluable. Pretreatment immunological evaluation consisted of determination of delayed-type hypersensitivity to recall antigens, enumeration of E-rosettes in blood, and measurement of blood lymphocyte response to phytohemmagglutinin (PHA) and concanavalin A (Con-A). The disease-free interval was correlated with thymosin dose and parameters of immunocompetence. Immunocompetent melanoma patients treated with a high thymosin dose and BCG relapsed earlier than those treated with a low thymosin dose and BCG. Thus, 72% of the melanoma patients who had a PHA SI≥50 and were treated with 4 mg thymosin/m2, were disease-free at 9 months, compared with only 31% of those treated with 40 mg/m2 (P=0.02). When the dermatophytin delayed hypersensitivity response (〉10 mm induration) was used as a parameter of immunocompetence, 86% of the patients treated with 4 mg/m2, were disease-free at 9 months, as against 28% of patients treated with 40 mg thymosin/m2 (P=0.07). None of the immunoincompetent patients on high thymosin dose relapsed (0/3). The results suggest that while a high thymosin dose (40 mg/m2) may be detrimental to immunocompetent patients, it may have a beneficial effect in immunoincompetent patients. A low thymosin dose is probably not detrimental to immunocompetent melanoma patients in this study. Monitoring of the immune status prior to and during the use of thymosin in cancer immunotherapy is mandatory.

Notes: Abstract The administration of Bacillus Calmette-Guérin (BCG) has been associated with restoration of general immunocompetence, augmentation of specific tumor immunity, activation of local and regional host defense mechanisms, and stimulation of the reticuloendothelial system. There is evidence that antigens from a variety of unrelated tumors are shared with, or are similar to, antigens in BCG. However, it is uncertain whether this cross-reactivity is the basis for the antitumor activity of BCG. Numerous studies emphasize the importance of regional effects of immunotherapy. They suggest a two-step mechanism for antitumor activity that involves recognition of BCG by host defense mechanisms, followed by activation and mobilization of macrophages by specifically produced lymphokines. The several nonviable derivatives of BCG have activity comparable to BCG without many of the problems associated with viable BCG. An optimal, completely standardized BCG preparation has not yet been produced. Clinical studies on the immunotherapeutic effects of BCG and its derivatives in cancer patients indicate that in cutaneous malignant melanoma, intralesional injection of BCG causes complete regression of tumor in 65–90% of instances, with long-term remission in patients with purely cutaneous metastatic disease. In patients with disseminated malignant melanoma, studies show prolongation of remission duration and overall survival in patients undergoing chemoimmunotherapy (with BCG + imidazole carboxamide) over those receiving chemotherapy alone. In acute lymphoblastic leukemia, one study has found a greater than 90% probability of survival in patients with the microlymphoblastic type undergoing immunotherapy after 5 years, yet other studies fail to show any therapeutic advantage. In most studies in acute myeloblastic leukemia, immunochemotherapy has given both qualitative and quantitative improvements in remission duration and particularly survival. Increased survival, particularly in stage I patients, has been reported in a trial of adjuvant BCG immunotherapy in lung cancer. Other studies on carcinoma of the colon, breast, and the head and neck, soft tissue sarcomas, and genitourinary cancers, utilizing various combinations of BCG and its derivatives, and chemotherapy, surgery, or radiation therapy indicate enhanced remission duration and survival. However, more research is needed to determine the optimum therapy combination in each case, to make refinements in dose, route, and schedule of administration, to improve product characteristics, and to overcome the complications of BCG immunotherapy.

Notes: Abstract The rapidly emerging therapeutic modality of cancer immunotherapy has been applied to a carefully selected group of patients with carcinoma of the large bowel. Patient selection was based on the extent of disease at the time of definitive surgery, and the strict provision that all discernible disease was removed. Thus, 20 consecutive patients who had mesenteric lymph node involvement were subsequently allocated to receive either BCG alone or the combination of 5-FU plus BCG as adjuvant treatment to surgery. After 10 months of patient accrual, all patients were clinically free of disease. Therapy was well tolerated without significant morbidity. Although general immunocompetence of these patients has improved on treatment, it is still too early to say whether immunotherapy will be clinically beneficial. Serial determination of plasma levels of CEA was useful in ruling out suspected recurrent disease. In contrast, preoperative plasma levels of CEA in patients with Dukes' C classification were elevated in only 40%. This indicates that its value in establishing the primary diagnosis is still doubtful.