[Primitive neuroectodermal tumor of the testis. Molecular analysis and discussion of genesis]. / Primitiver neuroektodermaler Tumor im Hoden. Molekulare Analyse und Diskussion der Entstehung.

We describe a case of a testicular primitive neuroectodermal tumor (PNET) with intratubular germ cell neoplasia of the adjacent testicular parenchyma. The occurrence of testicular PNET is rare because malignant transformation of testicular germ cell tumors into somatic malignancy is uncommon. Based on morphological, immunohistochemical and molecular pathological findings these tumors resemble central PNETs as they otherwise typically occur in children without rearrangement of the Ewing sarcoma breakpoint region (EWSR) gene on chromosome 22. This case also showed no evidence for a translocation.

[Birt-Hogg-Dubé syndrome : bilateral oncocytic kidney tumors in a patient]. / Birt-Hogg-Dubé-Syndrom : Bilateraler onkozytischer Hybridtumor der Niere.

We report on a rare case of bilateral oncocytic kidney tumors in a patient with Birt-Hogg-Dubé syndrome (BHD). BHD is an autosomal inherited cancer syndrome associated with multiple kidney tumors, benign cutaneous tumors, and pulmonary cysts with spontaneous pneumothorax. To date about 50 BHD families have been described. Patients are best treated with nephron-sparing surgery. Close follow-up is mandatory because recurrence in previously operated kidneys and metastatic tumor progression can occur. Family members at risk should also early be screened for BHD.

T-level downstaging and complete pathologic response after preoperative long-term radiochemotherapy for locally advanced rectal cancer.

Advantages of neoadjuvant chemoradiotherapy for locally advanced carcinoma of the middle and the lower third of the rectum are downstaging and downsizing of the tumor. Results of pathologic results are affected by post-treatment tissue changes and may influence the choice of surgical procedure. Forty-three consecutive patients (27 male, 16 female; mean age 64 years) were operated after receiving a long-term chemoradiotherapy during a period of 16 months. The data of initial staging procedure (high resolution magnetic resonance imaging) and results of pathological examination of the surgical specimens were analyzed. Regression of tumor was assessed by the absence of vital tumor cells and the post-treatment fibrotic tissue alterations. Regression of tumor size was seen in 42/43 patients leading to an improved T-stage in 27 patients. R0-resection was possible in all cases, although there was a perirectal tumor infiltration to less than 2 mm to circumference of the surgical specimen in 2 cases and unexpected small liver metastasis in 5 cases. Complete remission rate was 23.3% (10 cases). Detecting small amounts of vital tumor cells in altered tissue after chemoradiotherapy is a major problem of pathological examination procedure and should be taken into consideration by the surgeons. The choice of operation (resection vs. abdominoperineal extirpation vs. local excision) should be committed to the initial imaging procedure and not to any restaging procedure after neoadjuvant chemoradiotherapy.

Differentiation towards gastric foveolar, mucopeptic and intestinal goblet cells in gallbladder adenocarcinomas.

Cellular differentiation in 22 surgically removed adenocarcinomas of the gallbladder was immunohistochemically studied with antibodies specific to mucins of gastric foveolar cells (M1), (pseudo)pyloric cells (M2) and intestinal goblet cells (M3), and also with antibodies against pepsinogen II and chromogranin A. More than 70% of tumours (16 of 22 cases) displayed gastric- and/or intestinal-type differentiation, most of which (12 of 16 cases) showed both types of differentiation. Two tumours showed an organoid growth pattern similar to the normal gastric mucosa. The presence of endocrine cells positive for chromogranin A was closely related to that of gastric- and/or intestinal-type cells. The present findings clearly indicate the multidirectional differentiation of gallbladder adenocarcinomas and suggest that most gallbladder adenocarcinomas develop and progress under induction of gastric and intestinal differentiation.

[Glomus tumor--a rare stomach tumor]. / Der Glomustumor--ein seltener Magentumor.

We report on a 72 year old woman with a large glomus tumor of the stomach is given. The difficulty of preoperative diagnostics is described, and the importance of immediate section of microscopic examination during surgery in order to minimize the extent of resection is shown. Gastric glomus tumors are rare, benign, and normally solitary lesions in the antrum or pyloric region. When the exact intraoperative diagnosis is possible, a local excision is seen as a sufficient treatment.

Assessment of proliferative activity in carcinomas of the human alimentary tract by Ki-67 immunostaining.

The monoclonal antibody (MAb) Ki-67, which is directed against a proliferation-associated nuclear antigen, was used to measure tumor proliferation in 165 carcinomas of the esophagus, stomach, colon and rectum with an indirect immunoperoxidase technique. The percentage of Ki-67-positive tumor cells (Ki-67 index) was evaluated with the point-counting method. The Ki-67 index in gastric cancers (mean, 24.8%; standard deviation, 11.1%) was significantly lower than in tumors of the esophagus (35.7 +/- 12.6%), colon (37.6 +/- 15.2%), and rectum (34.3 +/- 16.4%). A wide range of the Ki-67 index (5.9-75.3%) could be observed within the various tumor types. In recurrent colorectal carcinomas, the Ki-67 index significantly increased to 51.9%. The Ki-67 index was independent of pathologic (e.g., TNM-stage, grading, tumor volume, tumor site) and clinical variables (age and gender of the patients). A marked heterogeneity of Ki-67 expression within different tumor stages was noted. Statistically significant regional variations in tumor proliferation existed between different areas within the same tumor.

[The disease picture of melorheostosis]. / Zum Krankheitsbild der Melorheostose.

The rare syndrome of Lér's melorheostosis is described on the basis of a case encountered in one of our own patients, a 29 year old male patient. Particular attention is given to the symptoms, the specific results of clinical examination, and the differential diagnosis.

Assessment of cell proliferation in colorectal carcinomas using the monoclonal antibody Ki-67. Correlation with pathohistologic criteria and influence of irradiation.

Cell proliferation was measured by a three-step immunoperoxidase technique on cryostat sections of 61 resected colorectal adenocarcinomas using the monoclonal antibody Ki-67 that is directed against a proliferation-associated nuclear antigen. The percentage of Ki-67-positive cells was quantified with the point-counting method. The frequency distribution of the percentage of Ki-67-positive tumor cells in 52 unirradiated carcinomas was gaussian with a mean of 38.7% (range, 7.7% to 75.3%). Analysis of the unirradiated tumors showed no relation between Ki-67 staining and various clinicopathologic features including age, sex, tumor volume, tumor differentiation, location, and tumor stage. Although some tumors demonstrated intratumor heterogeneity of immunoreactivity, there was no significant difference in proliferative activity among peripheral, intermediate, and central tumor areas. Whereas the Ki-67 index increased to 47.1% in recurrent carcinomas, it decreased significantly to 24.7% in rectal carcinomas given radiotherapy before surgery. Therefore, Ki-67 immunostaining might be used as a tool to select and monitor patients with colorectal cancers who might benefit from radiotherapy. The marked differences of Ki-67 expression among different tumors may relate to heterogeneity in growth kinetics and may therefore carry prognostic implications.

Critical evaluation of histochemical and immunochemical methods for the demonstration of vascular supply in rectal and oesophageal cancer.

The vascularisation of rectal and oesophageal carcinomas and of normal mucosa was studied using histochemical and immunohistochemical methods. Endothelial cells were stained for alkaline phosphatase (AP) using an azo-dye procedure. Histochemical results were compared with the immunohistochemical identification of endothelial cells using the monoclonal antibody BW 200 recognising an epitope restricted to human endothelial cells. In the AP experiments the simultaneous reactivity of stromal tissue often precluded the exact evaluation of tumour blood vessels. Immunohistochemistry facilitated the identification of vessels in neoplastic tissues and allowed a quantitative analysis of vascular volume by means of point-counting. Vascular volumes of normal tissues exceeded those of tumours by a factor of 1.6. This immunohistochemical technique has potential application in studying the importance of tumour blood supply in man, especially in relation to radiotherapy.

Lung extravascular volume during venovenous bypass with extracorporeal CO2-removal in dogs.

Extracorporeal circulation can cause lung damage, which would be especially counterproductive during extracorporeal gas exchange for the treatment of acute respiratory failure. To test the hypothesis that partial venovenous bypass with extracorporeal CO2-removal combined with low-frequency positive pressure ventilation (ECCO2R-LFPPV) can adversely affect lung fluid balance, extravascular thermal lung volume (ETV) and hemodynamics were assessed before, during and after ECCO2R-LFPPV in normal closed chest dogs. In series I dogs (n = 6) subjected to 10 h of ECCO2R-LFPPV, ETV did not change significantly from control (7.1 ml/kg +/- 0.99 SE) during or after bypass. Gravimetric extravascular lung water and lung histology after bypass were found to be normal. In series II dogs (n = 5), subjected to shorter periods of ECCO2R-LFPPV, ETV also remained unchanged. In contrast to previous reports using sheep, pulmonary arterial hypertension during bypass was not observed. Thus, ECCO2R-LFPPV was not associated with increased lung water, pulmonary hypertension or morphological lung changes under the conditions studied and does not seem to cause lung damage in normal lungs.