Pathology of carcinoma in situ of the urinary bladder and related lesions

The current classification of urothelial neoplasms

The classification of urothelial neoplasms has been a subject of significant controversy and debate over the last decade. Only recently has a general level of agreement developed on the utility of the classification first proposed by the World Health Organization and the International Society of Urologic Pathology in 1998. Recent adoption of this scheme in therapeutic guidelines indicates the clinical utility of the system. In this review a brief historical perspective is presented, followed by a review of the classification system, the histological criteria for the specific categories and the clinical significance of these diagnoses.

Cellular morphological parameters of the human urinary bladder (malignant and normal)

The normal and malignant cellular morphological parameters (intra- and extracellular spaces of the human urinary bladder) were obtained from analysis of digital images of bladder histology sections. Then these cellular morphological parameters were compared with the same parameters obtained from the literature for the bladder tissue. However, the limited quantitative data about these parameters available in the literature for bladder cell sizes and other geometrical parameters such as extra-cellular space does not provide a scientific basis to construct accurate structural models of normal and malignant bladder tissue. Therefore, there is usually no quantitative discussion of cell sizes in literature but the measured data in this work can provide a reasonable estimation of expected morphological parameter changes of bladder tissue with pathology. To produce this quantitative information, and also, to build a suitable models in another study using electrical properties of the tissue, 10 digital images of histological sections of normal, and six sections from malignant areas of the human urinary bladder, were chosen randomly (ex vivo). Finally, the measured data showed that there is a significant difference between the cell dimensions (in basal and intermediate layers) of normal and malignant bladder tissues.

Urinary bladder biopsy with denuded mucosa: Denuding cystitis?Cytopathologic correlates

Denuding cystitis is often encountered in tissue biopsies of bladder mucosa performed by either cold-cup forceps or wire loop electrocautery to evaluate hematuria or to rule out recurrent urothelial carcinoma. Lack of urothelium in these biopsies is often a frustrating experience, leading to a nonspecific interpretation. In this study, 151 cases of denuding cystitis were retrieved from the surgical pathology files of The Johns Hopkins Hospital over a 4-year period (1996-1999). Patients under the age of 40 years and outside consultation material were excluded. Of the 151 cases of denuding cystitis, 48 patients were identified who had concurrent urinary cytologic studies. Of these patients, 35 were male (73%) and 13 were female (27%). Patient ages ranged from 43 to 85 years (mean, 67). Twenty-six of these 48 patients (54%) had at least one concurrently positive urinary cytology, which was histologically confirmed. All except three cases were high-grade urothelial carcinoma with the following histologic subtypes: flat carcinoma in situ (n = 11), noninvasive papillary (n = 9), and invasive urothelial carcinoma (n = 3). We conclude that urinary cytology is a sensitive modality that detects exfoliated carcinoma cells in patients with a histologic diagnosis of denuding cystitis. An inconclusive diagnosis of denuding cystitis on tissue might be related to biopsy method and technique, small sample size, or biopsy of cystoscopically abnormal urothelium that is denuded. A cytologic diagnosis of high-grade urothelial carcinoma in these cases leads to a timely clinical intervention for optimal patient management.

Southwest Oncology Group studies in bladder cancer

Over 50,000 patients are diagnosed annually with bladder cancer, and approximately 10,000 eventually will die of their disease. Thus, the Southwest Oncology Group (SWOG) Genitourinary Cancer Committee is committed to the study of therapeutic interventions in patients with superficial, invasive, and metastatic bladder cancer. In the past 15 years, SWOG has completed six Phase III, randomized trials. Studies in patients with superficial disease have established the role of bacillus Calmette-Guerin in patient management; and a large, randomized trial has outlined the value of neoadjuvant chemotherapy and cystectomy in patients with advanced disease. SWOG plans to build on this model by evaluating patients with residual disease after chemotherapy for possible bladder preservation while evaluating more chemotherapy for patients with persistent disease. The Genitourinary Cancer Committee will continue to seek new, active agents for metastatic disease and will participate in and support large, Phase III, international trials that seek to improve current regimens. SWOG accomplishments in bladder cancer are highlighted, and future strategies are discussed.

Clinical significance of thymidylate synthase expression in bladder cancer

BACKGROUND

The purpose of the present paper was to investigate the clinical significance of thymidylate synthase (TS) expression in bladder cancer and its association with proliferation markers, such as p53, Ki-67, and proliferating cell nuclear antigen (PCNA).

METHODS

Thymidylate synthase gene expression in 54 patients with bladder cancer was measured by the reverse transcription polymerase chain reaction (RT-PCR) method using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. The TS expression was also examined immunohistochemically. Immunohistochemical studies of p53, Ki-67, and PCNA expression were carried out to examine the correlation between TS expression and the expression of proliferation markers in the tumors. Prognostic and clinical outcome factors such as vascular invasion and distant metastasis were also examined along with TS expression.

RESULTS

Twenty-four patients with invasive bladder cancer had TS levels of 5.07 +/- 0.77 (mean +/- SE), while 30 patients with superficial bladder cancer had TS levels of 2.28 +/- 0.38. There was a significant difference in TS levels between invasive and superficial bladder cancer (P = 0.001). There was a positive correlation between TS expression and each proliferation marker of p53 (r = 0.686, P < 0.01), Ki-67 (r = 0.715, P < 0.0001) or PCNA expressions (r = 0.670, P < 0.0001) in these patients. Patients with high TS levels (TS > or = 2.63, the median value) had significantly higher rates of vascular invasion and distant metastasis. Kaplan-Meier analysis demonstrated that patients with high TS levels (TS > or = 2.63) had unfavorable prognosis compared to patients with low TS levels (TS < 2.63; P = 0.034). Furthermore, patients with high TS staining had a significantly poorer prognosis than those with low staining (P = 0.012).

CONCLUSION

Determination of level of TS expression may help in the selection of an appropriate treatment for bladder cancer because TS expression influences the biological characteristic of bladder tumor.

Morphologic expressions of urothelial carcinoma in situ: a detailed evaluation of its histologic patterns with emphasis on carcinoma in situ with microinvasion

The recently proposed World Health Organization/International Society of Urological Pathology (WHO/ISUP) consensus classification of flat urothelial lesions expands the definition traditionally used for urothelial (transitional cell) carcinoma in situ (CIS), basing its diagnosis predominantly on the severity of cytologic changes. Lesions now encompassed within the diagnosis of CIS exhibit an array of cytologic and architectural features, which have not been documented in detail. In this study, cases were examined with respect to histologic patterns and microinvasion (invasion into the lamina propria to a depth of less than 2 mm). Five major patterns of CIS, often occurring in the same specimen (160 patterns in 77 cases), were noted. Common to each pattern was the presence of high-grade cytologic atypia, the definitional feature. The patterns found include 1) large cell CIS with pleomorphism (57%), in which the cells had abundant cytoplasm and nuclear pleomorphism; 2) large cell CIS without nuclear pleomorphism (48%); 3) small cell CIS (14%), in which the cytoplasm was relatively scant and pleomorphism was usually minimal; 4) clinging CIS (40%), in which the urothelium was denuded with a patchy, usually single layer of atypical cells; and 5) cancerization of urothelium (16%) with either pagetoid spread (clusters or isolated single cells) or undermining or overriding of the normal urothelium. Carcinoma in situ with microinvasion into the lamina propria (13 cases: 3 of 77 CIS cases studied above and 10 additional cases) was evident as invasive cells with retraction artifact mimicking vascular invasion (77%, 10 cases); nests, irregular cords, and strands, or isolated single cells with desmoplasia (8%, 1 case); or absent stromal response (15%, 2 cases). Although the diagnostic terminology for all of these patterns, for the purposes of the surgical pathology report, should be simply urothelial CIS with no specific mention of the morphologic pattern, awareness of the histologic diversity of CIS will facilitate the diagnosis of this therapeutically and biologically critical flat lesion of the urothelium. These lesions may be associated with microinvasion, which may be clinically unsuspected and histologically subtle.

Diagnosis and grading of bladder cancer and associated lesions

Standardized classification and grading of urothelial carcinoma has now been achieved internationally. Uniformity of pathologic reporting should improve the comparability of different studies and therapies and provide more accurate information to urologists in managing patients.

Possible factors affecting response to intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy for carcinoma in situ of the bladder: a multivariate analysis

To evaluate clinicopathological factors affecting response to intravesical instillation therapy with the bacillus Calmette-Guérin (BCG) Tokyo 172 strain for carcinoma in situ (CIS) of the bladder, we reviewed data for 84 patients treated between 1985 and 1996. Median follow-up was 56 months. The patients comprised three groups: primary (only the in situ lesion, 31 patients), subsequent (found after treatment of a gross neoplasm, 20), and concomitant (found together with a gross neoplasm, 33). A complete response was found in 62 (74%) of the 84 patients. Intravesical BCG therapy eradicated tumour cells in 74% of the primary group, 70% of the subsequent group, and 76% of the concomitant group. Multivariate logistic regression analysis revealed that the presence of gross haematuria and patient age were significantly associated with a complete response to the intravesical BCG therapy (p<0.05). On the other hand, gender, irritative bladder symptoms, type of extent of CIS, histological grade of CIS, BCG dose, and number of times BCG was given did not exert any significant influence. The 5-year recurrence rate was 33% for the 62 patients for whom a complete response was once achieved. Patients aged 60 or older had a higher probability of recurrence than those less than 60 years of age (p<0.05). Disease progression was found in 13% of the 84 patients and total cystectomy was performed in 19%. The present finding that patient age is related to the response to intravesical BCG therapy may point to a role for the reduced host immunocompetence in elderly individuals.

Intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy for carcinoma in situ of the bladder

To evaluate the clinical response to intravesical instillation therapy with bacillus Calmette-Guérin (BCG) Tokyo 172 strain for carcinoma in situ (CIS) of the bladder and subsequent patient prognosis, we reviewed data for 30 patients treated between 1985 and 1994. Median follow-up was 56 months. The CIS cases comprised two groups: primary (19 patients) and subsequent to development of a gross neoplasm (11 patients). Either 40 mg (n = 20) or 80 mg (n = 10) doses of BCG were instilled weekly for 8 weeks. This intravesical therapy resulted in apparent eradication of tumour cells in 25 of the 30 patients for a complete response (CR) rate of 83%, with no difference found between primary and secondary groups. Tumours later recurred in 6 of the 25 patients (24%) and disease progression was found in only 3 (12%). In contrast, progression occurred in 3 of 5 patients (60%) for which a complete response was not achieved with intravesical BCG therapy. The difference between these two groups was significant (p = 0.04). Total cystectomy was performed in 2 of 25 CR patients (8%) first and in 4 of the 5 unresponsive (80%), the statistical difference being highly significant (p = 0.003). The 5-year survival rate was 96% for the study subjects as a whole. In conclusion, CIS unresponsive to BCG therapy should be treated with immediate total cystectomy while cases demonstrating a complete response should be followed up for a long period.

Carcinoma in situ of the urinary bladder. Clues to host involvement in human carcinogenesis

BACKGROUND

Carcinoma in situ (CIS) of the urinary bladder is a neoplasm of uncertain biologic behavior. It rarely occurs as the primary disease and exists most often in association with high grade, invasive tumors. The unfavorable prognosis ascribed to CIS may not be due to tumor-related factors but to low host resistance or to host-tumor relationships established for previous or co-incident invasive cancers. The scant available evidence indicates that a large proportion of patients with primary CIS have a low frequency of muscle invasion and death from disease.

METHODS

Of 2000 patients with bladder neoplasms in our pathology files and tumor registry, 102 had CIS confirmed on histologic review. There were 29 cases of primary CIS and 73 cases of secondary CIS. These cases were compared, with an emphasis on patient outcome.

RESULTS

The data indicate that primary and secondary CIS are histologically identical lesions whose effect on patients is related mainly to the presence of multifocal disease, often associated with previous or coincident invasive cancers. Progression or death from disease is unusual among patients presenting with primary CIS but common among individuals with CIS associated with other bladder cancers.

CONCLUSION

The authors suggest that the appearance of urothelial CIS identifies patients with at least localized resistance to the development of invasive bladder cancer. The degree of patient resistance to carcinogenic events leading to bladder carcinoma is manifested by the type, grade, and stage of their initial neoplasms.