· Stage 0 (Ta or Tis, N0, M0): Cancer cells found only on the inner lining of the bladder (This stage is often called Stage Ta).
· Stage I (T1, N0, M0): Cancer cells have proliferated to the layer beyond the inner lining of the urinary bladder but not to the muscles of the urinary bladder.
· Stage II (T2, N0, M0): Cancer cells have proliferated to the muscles in the bladder wall but not to the fatty tissue that surrounds the urinary bladder.
· Stage III (T3 or T4a, N0, M0): Cancer cells have proliferated to the fatty tissue surrounding the urinary bladder and to the prostate gland, vagina, or uterus, but not to the lymph nodes or other organs.
· Stage IV: Cancer cells have proliferated to the lymph nodes, pelvic or abdominal wall, and/or other organs (Figure 2.3 & 2.4).
· Recurrent: Cancer recurred in the urinary bladder or in another nearby organ after being treated.
BC cells are described as well differentiated, moderately differentiated, or poorly differentiated. Differentiation is a term used to describe how clearly the cancer cells can be distinguished from the surrounding normal tissues and how normal or abnormal the cells look.
· GX: Grade cannot be assessed.
G1: Well-differentiated cancers have very clear boundaries and cells that look relatively normal. They usually do not grow and spread rapidly.
G2: Moderately differentiated cancer has more abnormal looking cells and cell boundaries.
G3-4: Poorly differentiated cancers have less-clearly defined boundaries and cells that look very abnormal. They often grow and spread rapidly.
In 1998, World Health Organization/International Society of Urological Pathology (WHO/ISUP) classified BC tumors to define group of patients with different clinical outcomes (Busch & Algaba, 2002). The present recommended nomenclature (2004) is similar to the WHO/ISUP classification 1998, but the diagnostic criteria have been further defined (Eble et al., 2004). The latest 2004 classification avoid ambiguous grading such as grade I/II or II/III. The new system classifies tumors in two categories.
1. Papillary Urothelial Neoplasm of Low Malignant Potential (PUNLMP):
The papillae of PUNLMP are discrete, slender and none fused and are lined by multilayered urothelium with minimal to absence of cytologic atypia. The cell density is more than normal. The nuclei are slightly enlarged and tumors are predominantly diploid. Mitosis is rare and has a basal location.
2. Papillary Urothelial Neoplasm of High Malignant Potential (PUNHMP):
The tumor is characterized by a papillary architecture in which the papillae are frequently fused and branching. In contrast to UNLMP, it is easy to recognize more marked variations in nuclear polarity, shape, and size and chromatin pattern. The nuclei often show pleomorphic with moderate to marked variation in size and irregular chromatin distribution. Mitosis is frequent, may be atypical and occur at any level, including the surface.
BC is the fourth common cancer among all other cancers (Siegel et al., 2016) and is the second most common genitourinary malignancy (United Cancer Society, 2010). BC occurs primarily in men older than 60 years of age and roughly twice as frequently in white compared to black men. BC is nearly 3-4 times more common in men than in women (Shariat et al., 2010). The incidence in India is comparatively low and it is 3.2 in males and 0.7 in females/hundred thousand people (Sinha et al., 2003)