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In most populations, the occurrence of bladder cancer is 3–4 times more frequent in men than in women. 1 This reflects the more frequent exposure of men to tobacco-smoking and to occupations that imply contact with some chemicals, like aromatic amines, which are the two major recognized risk factors for bladder cancer. 2 – 5

Carcinoma of the bladder continues to be a common and serious healthcare problem. In 2001, 56,500 new cases of bladder cancer were diagnosed in the United States, and 12,600 people died of this disease. 1 Bladder cancer is the fourth most common solid tumour in men and the eighth most common in women, ranking seventh and tenth, respectively, among causes of cancer death. 1 The term ‘bladder cancer’ encompasses all primary malignancies of the bladder, but transitional cell carcinoma (TCC) is by far the most prevalent and well studied, and for these reasons is the focus of this chapter.

Non-invasive testing for bladder cancer has been carried out for many years by means of urine testing for blood, the presence of malignant cells on cytological examination and assessment of DNA ploidy in voided urine or bladder washings.

About 30% of all patients with newly diagnosed bladder cancer will present with muscle-invasive disease and about half of them will eventually die from the disease, despite mutilating surgery or polychemotherapy. The steps underlying tumour progression are invasion and metastasation. Thanks to the achievements of molecular biology, these processes are increasingly better understood. The new results arising will be eventually translated and incorporated into our current clinical knowledge. They form the basis for future strategies to manage locally advanced or metastatic bladder cancer.

Bladder cancer is a heterogeneous disease. The extent of this malignancy is highly correlated with its prognosis and with the options to treat it. Clinicians can only decide the appropriate therapy if they are informed as completely as possible how bladder cancer has affected the parent organ and its surroundings, the lymph nodes and the distant organs by possible metastases. Therefore an adequate staging system is necessary. Such a staging system should be adopted by a majority of clinicians, radiologists and pathologists. The system should provide clear-cut, standardized methodology for the classification of the extent of the disease. Only then is it possible to predict prognosis, to adequately decide treatment and to compare treatment results on an international basis. International clinical trial organizations such as EORTC (European Organization for Research and Treatment of Cancer) cannot perform their work without having an appropriate staging system.

In the Western world, the most frequently encountered pelvic diseases are neoplasms. Urinary bladder and prostate cancer are the most common diseases of the male pelvis seen by radiologists. This paper focuses on these diseases. MR (magnetic resonance) imaging is the most promising technique in visualizing these tumours, and the emphasis of this paper is on this imaging modality.

Bladder cancer is a heterogeneous disease with considerable variations of its natural history, with five-year survival rates ranging from 97–98% of a monofocal, well-differentiated and small papillary tumour to 0% of an invasive bladder cancer extending throughout the bladder wall and with gross nodal metastases. 1 Among superficial bladder cancers, tumour recurrence after initial therapy varies from 30% in patients with a solitary papillary tumour to more than 90% in patients with multiple tumours. 2 Most tumours recur in six to 12 months but remain non-invasive and pose little risk to the patient.

Surgery plays a major role in the treatment of all stages of invasive bladder cancer. The rationale for surgery in the case of invasive bladder cancer is based on the fact that the natural history of high-grade bladder cancer is to progressively invade through the lamina propria into the muscolaris propria, perivesical fat and adjacent pelvic structures. 1 Moreover, transitional cell carcinoma seems substantially resistant to radiation therapy, even though this therapeutical option hasn’t been fully evaluated. 2 , 3 Finally, other treatment modalities, such as chemotherapy and bladder sparing techniques (partial cystectomy and/or extended transurethral resection), alone or in combination, seem not to provide the same results in terms of long-term disease-specific survival rate if compared to radical cystectomy, even though no comparative data in this regard are available. 2 – 6

Radical cystectomy is the gold standard therapy for patients with invasive bladder cancer. However, in patients with locally advanced disease, survival is not completely satisfactory, promoting the development of combination therapies, and associating chemotherapy to cystectomy. 1 , 2 In patients with low local stages, radical cystectomy can be an overtreatment, according to the literature, where the absence of residual tumour (p0) on cystectomy specimens is around 12%. 3 – 6 This absence of residual tumour does not necessarily mean that patients are cured with cystectomy, however, as the five-year survival rate was 67% in Pagano’s series. 4 This decrease in survival is essentially related to the development of distant metastasis due to the presence of micrometastasis at the time of cystectomy. Consequently, a p0 after cystectomy only means that the tumour was completely removed by transurethral resection (TUR) during the clinical assessment and patients were probably overtreated because cystectomy does not have any, or at least only minimal, impact on micrometastases.

Radical cystectomy and bilateral pelvic lymph-node dissection (PLND) has been established as standard treatment for muscle-invasive bladder cancer. 1 , 2 As regards lymph-node involvement, it has clearly been shown that the presence of nodal metastasis is an indication for at least limited systemic tumour spread, and does translate into decreased survival compared to node-negative patients, despite radical surgery. However, recent data indicate that patients with minimal nodal disease and otherwise organ-confined primary bladder tumours do benefit from radical cystectomy and PLND, and that even a proportion of patients with grossly node-positive bladder cancer can be cured by surgery and thorough lymph-node dissection. 3 – 7