Pathology and genetics of tumours of the urinary system and male genital organs

/pdf/pathology-and-genetics-of-tumours-of-the-digestive-system-3xy9cwrc3c.pdf

Pathology and genetics of tumours of the digestive system

https://repositori.upf.edu/bitstream/handle/10230/25890/Campuzano_cel_tum.pdf;sequence=1

Tumor induction by an endogenous K-ras oncogene is highly dependent on cellular context

Pathology and genetics: Tumours of the digestive system

There have been few reports on (1) the nature and pathogenesis of small cystic lesions of the pancreas, (2) their incidence, age distribution, and location, and (3) their significance as potential precursors of intraductal papillary tumors, mucinous cystic tumors, and duct cell carcinomas. Materials: Epithelial growth of small cystic lesions in 300 consecutive autopsy cases and in seven cases of small duct cell carcinoma from among 2300 elderly autopsy cases, was evaluated by histopathological analysis. One hundred eighty-six cystic lesions were found in 73 of 300 autopsy cases (24.3%). The incidence of cystic lesions increased with age. Cystic lesions were equally distributed throughout the pancreas. Epithelial atypia was histologically classified into five groups: normal epithelium; papillary hyperplasia without atypia; atypical hyperplasia; carcinomain situ; and invasive carcinoma. The incidence of each group was 47.5, 32.8, 16.4, 3.4, and 0%, respectively. Epithelia of atypical hyperplasia or carcinomain situ were more prevalent in small cystic lesions (less than 4 mm in diameter) than in larger lesions (chi-square test,p<0.05). Epithelia of dilated ductular branches adjacent to cystic lesions showed a similar degree of atypia as the epithelia of the cystic lesions themselves (p<0.01). Epithelial atypia of the main pancreatic duct was mild in all of the cases but two, and was not related to that of the cystic lesion. Among the seven cases of small duct cell carcinoma, two cases had small cancerous cystic lesions, 4.1 and 5.3 mm in diameter, within the tumor. Small cystic lesions appear to have the potential to progress to malignancy but definitive evidence has not been demonstrated. Additional studies, including molecular biological examinations, are necessary to fully understand the biology of these lesions.

Analysis of small cystic lesions of the pancreas

Three hundred and ninety-one cases of primary pancreatic tumours, excluding endocrine tumours, were studied histologically. Carcinoma of the exocrine pancreas formed the largest group (98.5 per cent), benign tumours (1.25 per cent) and other malignant tumours (0.25 per cent) formed the remainder. Ductal adenocarcinoma was the commonest type and was divided into four sub-types, papillary, well, moderately and poorly differentiated duct adenocarcinoma. The moderately and poorly differentiated tumours were the commonest types. Papillary carcinoma was separated from the well differentiated tumours by its different morphological appearances and was found to exhibit different behaviour. Other special morphological types of pancreatic carcinoma, pleomorphic, mucinous, adenosquamous, acinar, microadenocarcinoma, cystadenocarcinoma and oncocytic carcinoma were also represented. Benign microcystadenomata (four cases) were considered because of their interesting morphological features and their significance in the differential diagnosis of carcinoma. Based on the morphology and behaviour of these 391 tumours, the classification of pancreatic carcinoma is discussed and some rare types are compared with previously reported cases and discussed.

Morphological study of 391 cases of exocrine pancreatic tumours with special reference to the classification of exocrine pancreatic carcinoma.

Aim—To report the clinical and histological features and outcome of primary and secondary malignant lymphomas of the urinary bladder. 

Methods—Eleven cases of malignant lymphoma of the urinary bladder were obtained from the registry of cases at St Bartholomews and the Royal London Hospitals. The lymphomas were classified on the basis of their morphology and immunophenotype, and the clinical records were reviewed. 

Results—There were six primary lymphomas: three extranodal marginal zone lymphomas of mucosa associated lymphoid tissue (MALT) type and three diffuse large B cell lymphomas. Of the five secondary cases, four were diffuse large B cell lymphomas, one secondary to a systemic follicular follicle centre lymphoma, and one nodular sclerosis Hodgkins disease. Four patients with secondary lymphoma for whom follow up was available had died of disease within 13 months of diagnosis. Primary lymphomas followed a more indolent course. In one case, there was evidence of transformation from low grade MALT-type to diffuse large B cell lymphoma. The most common presenting symptom was haematuria. Cystoscopic appearances were of solid, sometimes necrotic tumours resembling transitional cell carcinoma, and in one case the tumours were multiple. These cases represented 0.2% of all bladder neoplasms. 

Conclusions—Diffuse large B cell lymphoma and MALT-type lymphoma are the most common primary malignant lymphomas of the bladder. Lymphoepithelial lesions in MALT-type lymphoma involve transitional epithelium, and their presence in high grade lymphoma suggests a primary origin owing to transformation of low grade MALT-type lymphoma. Primary and secondary diffuse large B cell lymphomas of the bladder are histologically similar, but the prognosis of the former is favourable. 

Key Words: bladder • lymphoma • mucosa associated lymphoid tissue lymphoma

https://jcp.bmj.com/content/jclinpath/53/6/458.full.pdf

Malignant lymphoma of the urinary bladder: a clinicopathological study of 11 cases

One hundred cases of transitional cell carcinoma of the 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.

https://jcp.bmj.com/content/jclinpath/42/11/1227.2.full.pdf

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

A retrospective analysis of the prognostic value of pretreatment histology and expression of human chorionic gonadotrophin (B-hCG) was carried out in 100 invasive (T2/T3) transitional cell carcinomas of the bladder treated in a uniform manner. After transurethral resection of the tumour, all patients received a course of radical radiotherapy, with salvage cystectomy for those who failed to respond. Forty-nine of 100 patients responded to radiation; thus 51 did not. Forty-seven of 60 (78%) patients whose tumours contained areas of squamous differentiation and 22 of 29 (76%) of tumours staining positively for HCG failed to respond to radiotherapy. Twenty-two of 23 (96%) patients with tumours that had both these features did not respond to radiotherapy. The other histological features studied (grade of tumour, necrosis, inflammation, vascular invasion, and growth pattern) appeared unrelated to each other or to clinical outcome.

Human chorionic gonadotrophin expression and histological findings as predictors of response to radiotherapy in carcinoma of the bladder

Three cases of cutaneous mixed tumor with atypical features are described. These biphasic tumors comprise cords and nests of often plasmacytoid cells with areas of tubule formation, set in a chondroid stroma. The tumor cells show immunohistochemical positivity for both CAM 5.2 and S-100 and ultrastructural features of myoepithelium. The atypical histological features of an infiltrative margin, satellite tumor nodules, and tumor necrosis, which were present in these cases, have been described in malignant chondroid syringoma; however, a review of the small number of previous case reports demonstrates that histological appearances did not always correspond with apparent malignant potential in this tumor. The term atypical mixed tumor is recommended for tumors in which there are histological features of malignancy, especially local invasion, without proven metastases. Complete excision of the tumor and careful follow-up are advised, as at present the malignant potential of these tumors cannot be reliably predicted from their histological appearance.

Atypical mixed tumor of the skin: histologic, immunohistochemical, and ultrastructural features in three cases and a review of the criteria for malignancy.

S. I. Baithun

Papers

Morphological study of 391 cases of exocrine pancreatic tumours with special reference to the classification of exocrine pancreatic carcinoma.

Malignant lymphoma of the urinary bladder: a clinicopathological study of 11 cases

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

Human chorionic gonadotrophin expression and histological findings as predictors of response to radiotherapy in carcinoma of the bladder

Atypical mixed tumor of the skin: histologic, immunohistochemical, and ultrastructural features in three cases and a review of the criteria for malignancy.