BCG in bladder cancer--a warning

Identification of substrains of BCG vaccine using multiplex PCR

Current methods for determining the identity of substrains of Mycobacterium bovis BCG (BCG) vaccine are labour intensive, or provide only limited substrain differentiation. In this paper we describe a multiplex PCR that distinguishes between M. tuberculosis (TB) and M. bovis and the non-pathogenic BCG strain, and also subdivides the BCG vaccine substrains investigated into seven distinct fingerprints based on six target regions in the DNA. This test is specific, rapid, reproducible and portable and is proposed as a novel test for BCG vaccine control. It offers substantial advantages over the methods currently in use. Using this test we have characterised a number of commercial BCG vaccines.

Cytogenetic monoclonality in multifocal uroepithelial carcinomas: evidence of intraluminal tumour seeding

Twenty-one multifocal urinary tract transitional cell carcinomas, mostly bladder tumours, from a total of six patients were processed for cytogenetic analysis after short-term culturing of the tumour cells. Karyotypically related, often identical, cytogenetically complex clones were found in all informative tumours from each case, including the recurrent tumours. Rearrangement of chromosome 9, leading to loss of material from the short and/or the long arm, was seen in all cases, indicating that this is an early, pathogenetically important event in transitional cell carcinogenesis. The presence of related clones with great karyotypic similarity in anatomically distinct tumours from the same bladder indicates that multifocal uroepithelial tumours have a monoclonal origin and arise via intraluminal seeding of viable cancer cells shed from the original tumour. Later lesions may develop also from cells shed from the so called second primary tumours. The relatively complex karyotypes seen in all lesions from most cases argue that the seeding of tumour cells is a late event that succeeds the acquisition by them of multiple secondary genetic abnormalities.

Bacillus Calmette-Guerin (BCG) immunotherapy for bladder cancer: review of complications and their treatment

BACKGROUND

Intravesical bacillus Calmette-Guerin (BCG) is widely used in the management of bladder cancer but because it is a living organism, local and disseminated infection may result.

METHODS

A prospective assessment of complications of this therapy in 200 patients in Queensland was performed. A review of management of complications of intravesical BCG was also carried out.

RESULTS

Major side effects were rare. Cystitis was the most common side effect, being seen to some degree in all patients, although only forcing cessation of BCG therapy in two patients. Two patients developed persistent cystitis necessitating institution of isoniazid and rifampicin. Two patients had culture-proven bladder infection that presented several months after the BCG treatment. These patients also responded to two-drug antituberculous therapy. While low-grade fever is very common with this therapy, seven patients (3.5%) had fevers of > 39 degrees C within 48 h of receiving BCG. Fevers may be an indication of severe disseminated mycobacterial infection, which has a high mortality, so it needs to be treated aggressively. Alternatively bacterial sepsis with gram-negative bacterial pathogens or a hypersensitivity reaction to BCG may cause this degree of fever, and cannot be rapidly distinguished from fulminant mycobacterial infection. One patient in the present series developed pneumonia attributed to mycobacterial dissemination.

CONCLUSIONS

The key to appropriate management of complications of BCG therapy is awareness of their possibility, even months or years after the therapy has been given. Appropriate empirical therapy in acute situations and mycobacterial culture in chronic situations can then be performed.