Local bacillus Calmette-Guerin therapy for superficial bladder cancer: clinical, histological and ultrastructural patterns

Intratumoral cancer chemotherapy and immunotherapy: opportunities for nonsystemic preoperative drug delivery

The recent literature documents the growing interest in local intratumoral chemotherapy as well as systemic preoperative chemotherapy with evidence for improved outcomes using these therapeutic modalities. Nevertheless, with few exceptions, the conventional wisdom and standard of care for clinical and surgical oncology remains surgery followed by radiation and/or systemic chemotherapy, as deemed appropriate based on clinical findings. This, in spite of the fact that the toxicity of conventional systemic chemotherapy and immunotherapy affords limited effectiveness and frequently compromises the quality of life for patients. Indeed, with systemic chemotherapy, the oncologist (and the patient) often walks a fine line between attempting tumour remission with prolonged survival and damaging the patient's vital functions to the point of death. In this context, it has probably been obvious for more than 100 years, due in part to the pioneering work of Ehrlich (1878), that targeted or localized drug delivery should be a major goal of chemotherapy. However, there is still only limited clinical use of nonsystemic intratumoral chemotherapy for even those high mortality cancers which are characterized by well defined primary lesions i.e. breast, colorectal, lung, prostate, and skin. There has been a proliferation of intratumoral chemotherapy and immunotherapy research during the past two to three years. It is therefore the objective of this review to focus much more attention upon intratumoral therapeutic concepts which could limit adverse systemic events and which might combine clinically feasible methods for localized preoperative chemotherapy and/or immunotherapy with surgery. Since our review of intratumoral chemoimmunotherapy almost 20 years ago (McLaughlin & Goldberg 1983), there have been few comprehensive reviews of this field; only one of broad scope (Brincker 1993), three devoted specifically to gliomas (Tomita 1991; Walter et al. 1995; Haroun & Brem 2000), one on hepatomas (Venook 2000), one concerning veterinary applications (Theon 1998), and one older review of dermatological applications (Goette 1981). However, none have shed light on practical opportunities for combining intratumoral therapy with subsequent surgical resection. Given the state-of-the-art in clinical and surgical oncology, and the advances that have been made in intratumoral drug delivery, minimally invasive tumour access i.e. fine needle biopsy, new drugs and drug delivery systems, and preoperative chemotherapy, it is timely to present a review of studies which may suggest future opportunities for safer, more effective, and clinically practical non-systemic therapy.

On the mode of action of intravesical bacillus Calmette-Guérin: in vitro characterization of BCG-activated killer cells

Previously we had shown that, upon activation with viable bacillus Calmette-Guérin (BCG), peripheral blood mononuclear cells (PBMNC) could be rendered cytotoxic against otherwise insensitive natural killer (NK)-resistant bladder cancer cell lines. This phenomenon had been termed the BCG-activated killer (BAK) cell phenomenon. By means of depletion and enrichment procedures of mononuclear cell subpopulations derived from BCG-activated PBMNC we further characterized the cytolytic BAK effector cells functionally in an in vitro cytotoxicity assay against the bladder carcinoma cell line BT-A and phenotypically in their pathway of activation. Neither macrophages nor CD4+ T-helper/inducer cells exerted cytotoxic BAK activity. This cytotoxicity was restricted to the CD8+CD56+ subpopulation of T-cytotoxic/NK cells. Furthermore, activation of BAK cells via interferon gamma (IFN-gamma) was evidenced by the complete inhibition of BAK cell generation with an IFN-gamma antibody.

Intravesical Bacillus Calmette-Guérin with the Danish strain for treatment of carcinoma in situ of the bladder

We report our experience of the treatment of carcinoma in situ (CIS) using intravesical therapy with the Danish Bacillus Calmette-Guérin (BCG) strain 331 (SSI). Forty-two patients received treatment, 11 had primary and 31 secondary CIS. The median follow-up period was 26 months (range 3-68). Patients received 6 weekly instillations (1 course) and non-responders an additional 6 instillations at 2-week intervals (2 courses). The complete response rate was 59% for 1-course patients, 33% for the 2-course patients and 68% for the entire series. Patients were considered treatment failures if they suffered progression to invasive cancer, metastasis or died from transitional cell carcinoma. BCG treatment was more effective in primary than in secondary CIS, with a complete response rate of 80% versus 65% and with no failures versus 35%. Patients with persistent CIS after the first course of BCG had a greater risk of failure than responders: 50% versus 17%. Patients with persistent CIS after the second course had a 75% failure rate. This suggests that cystectomy should be considered for non-responders following a 6-week course and recommended to those not responding to 2 courses. Ten patients had CIS in the prostatic urethra. All responded to BCG treatment; 2 suffered from recurrent CIS 1 associated with invasive urethral tumour. The incidence and severity of side effects were similar to those reported with other strains of BCG. One patient with primary CIS failed to complete the treatment owing to "BCG-itis".

Morphological aspects of the interaction of Bacillus Calmette-Guérin with urothelial bladder cells in vivo and in vitro: relevance for antitumor activity?

Intravesical administration of Bacillus Calmette-Guérin (BCG) has been shown to be effective in the treatment of patients with superficial bladder cancer. For a better understanding of the mechanism of this antitumor activity, scanning and transmission electron microscope (SEM, TEM) studies were carried out to investigate morphological aspects of the interaction of BCG with the bladder wall in vivo and in vitro. Adherence of BCG to the bladder wall in vivo was studied 1 and 24 h after single or multiple (6x) BCG instillations in intact and in electrocauterized guinea pig bladders. Despite extensive search with SEM for its presence, virtually no BCG was found on the intact urothelium, and BCG was only occasionally observed in the coagulation lesions. SEM and TEM studies revealed adherence and phagocytosis of BCG by the T24 human bladder carcinoma cell line in vitro. Time sequence studies on the phagocytosis and fate of BCG showed that T24 cells are capable of progressively degrading the mycobacteria in phagolysosomes. However, BCG did not alter MHC class II antigen expression on T24 cells in vitro. In contrast, 54 urine sediments and bladder washings of 11 bladder cancer patients, taken prior to or after several intravesical BCG instillations, failed to demonstrate urothelial (tumor) cells showing evidence of BCG phagocytosis (682 cells screened by TEM), while BCG was phagocytized avidly by leukocytes. These data suggest that a direct interaction of BCG with urothelial bladder cells in vivo can be called in question.