Clinical importance of squamous metaplasia in invasive transitional cell carcinoma of the bladder.

Abstract

SUMMARY One hundred cases oftransitional cell carcinoma ofthe bladder were studied to determine whether squamous metaplasia and other histological features within the bladder can be of value in predicting outcome of treatment with radiotherapy. Sixty cases showed the changes of squamous metaplasia, and of this group 46 (78%) failed to respond to radiotherapy. A significant response rate of 90% was seen in the 40 tumours without squamous metaplasia.It is concluded that transitional cell carcinomas of the bladder showing squamous metaplasia are mainly resistant to radiotherapy and alternative treatment methods should be sought.The heterogeneity of invasive bladder carcinoma has prompted many studies of histological features in an attempt to relate these to prognosis.`13 Most studies have been performed on radical cystectomy specimens, and there is little information about the histological features in transurethral resection material which may be relevant to the prognosis of patients, especially those treated with radiotherapy.The presence of squamous metaplasia is well recognised in transitional cell carcinoma of the bladder,45 but its importance for prognosis is not known. It has been shown that squamous cell carcinoma of the bladder is more resistant to radiotherapy than its transitional cell counterpart,67 and this aroused our interest in the responsiveness to radiotherapy of transitional cell carcinomas showing squamous metaplasia.It has been suggested that if radioresponsiveness of the tumour could be predicted more accurately before irradiation then non-responders could be offered alternative treatment including early cystectomy. We therefore undertook a study to determine whether the histological features of invasive transitional cell carcinoma of the bladder were related to or could be used to predict the response of the tumour to radiotherapy. Material and methodsFrom the records of the departments of urology and histopathology at this hospital 111 patients with muscle invasive transitional cell carcinoma of the bladder were identified (International Union Against Cancer (UICC) and American (Jewett) classification Accepted for publication 6 October 1988 stage T2/T3).' These patients presented between 1980 and 1985 and had received radiotherapy. Six cases with invasion of the prostate (UICC stage 4) were excluded as this group is recognised as having a poor prognosis and as being resistant to radiotherapy.8 In five cases the original pathology material was unavailable, thus leaving 100 cases. The mean age of patients was 68 3 years, range 33-85. There were 78 men and 22 women.The histological sections were processed from tissue fixed in 10% formol saline by standard techniques and stained with haematoxylin and eosin. The original tumours before treatment had been reviewed independently by three pathologists (JM, RZ, SB) unaware of the clinical outcome. Between one and seven blocks of tissue were available in each case (mean 2.6).The sections were assessed for grade using the WHO classification,5 degree and...

Urothelial Carcinoma with Squamous Differentiation is Associated with High Tumor Stage and Pelvic Lymph-Node Metastasis

“…2 Squamous differentiation, defined by the presence of intercellular bridges, keratinization, or both, is the most common variant, occurring in up to 20% of urothelial carcinomas of the bladder, followed by glandular differentiation. [3][4][5][6][7][8][9][10] Although urothelial carcinoma with squamous differentiation may be associated with poor prognosis, conflicting data have been reported regarding the role of squamous differentiation in unfavorable clinical outcomes. 7,[10][11][12][13][14][15][16] Because it is not uncommon for squamous differentiation to concurrently occur with other histological variants of urothelial carcinoma, such as micropapillary, glandular, and sarcomatoid differentiation, studies that report on mixed urothelial carcinoma variants may contribute to the discrepancies.…”

Selective Immunohistochemical Markers to Distinguish Between Metastatic High-Grade Urothelial Carcinoma and Primary Poorly Differentiated Invasive Squamous Cell Carcinoma of the Lung

“…2 Classifying UCas can be difficult in poorly differentiated tumors, as up to 60% display squamous features and because the pathologist is often faced with the task of making a diagnosis from biopsy specimens with limited tumor sampling. 3 Pure primary squamous cell carcinoma of the bladder is a relatively uncommon tumor, but it often presents at an advanced stage and has been associated with poor patient outcome. 4 The clinical need to discern primary bladder carcinomas from those secondarily arising in the genitourinary tract has sparked much interest in the discovery of molecular markers to distinguish UCa and guide prognostication.…”

1593 Comparative Outcomes of Pure Squamous Cell Carcinoma and Urothelial Carcinoma With Squamous Differentiation in Patients Treated With Radical Cystectomy

“…6,7 The incidence of SqD varies considerably among published series because no strict pathological criteria have been defined. 7,14,15 Histologically SqD is characterized by the presence of intercellular bridges or keratinization. The WHO recommended classifying SqD as a urothelial carcinoma and reserving the diagnosis of SCC for tumors composed of pure squamous cell carcinoma.…”