Presentation of a variation of the chorioallantoic membrane set up as a potential model for individual therapy for squamous cell carcinoma of the oropharynx.

The chorioallantoic membrane of fertilized chicken eggs in an early phase of breeding presents an approved test situation for the growth and treatment of human cancer cells.These models work due to the inoculation of cells into the membrane that stays within the egg shell during the time of investigation. In this study a modification of this model is presented. Samples of native tumors, rather than cell lines, are transplanted into the membrane and the body of the egg is taken out of the shell and placed in a plastic bowl. These modifications lead to an enhanced accessibility to the chorioallantoic membrane and the surrounding vessels thus facilitating intra venous access and application of pharmaceuticals and a focused radiotherapy. With the current modifications the embryo was kept alive and additionally, the vascularized tumor environment was preserved.

The role of beta-catenin mutation and SOX9 expression in sex cord-stromal tumours of the testis.

The WHO classification of testis tumours includes the group of sex cord-stromal tumours. They are divided into several histological types, i.e. Leydig cell (LCT) and Sertoli cell tumours (SCT). Based on the physiological expression of ß-catenin in normal testis/Sertoli cells, it was previously shown that SCT can carry a ß-catenin mutation, causing a nuclear positivity for ß-catenin and cyclin D1. Furthermore, it could be shown that the stabilization of ß-catenin in Sertoli cells causes the loss of the Sertoli cell marker SOX9. We wanted to know whether the stabilization of ß-catenin in sex cord-stromal tumours influences SOX-9 expression and thus could be used in the diagnosis of sex cord-stromal tumours. Therefore, 53 cases of sex cord-stromal tumours and tumour-like lesions were investigated for their immunohistochemical expressions of ß-catenin, cyclin D1 and SOX9. In addition, mutation analyses of the ß-catenin gene (exon 3; CTNNB1) were performed. ß-catenin mutation in SCT results in nuclear ß-catenin and cyclin-D1 expressions on immunohistochemical analysis. The nuclear expression/stabilization of ß-catenin causes the loss of SOX9 in these tumours. In contrast, SOX9 is considerably expressed in non-mutated SCT as well as in Sertoli cells of non-neoplastic testes. In summary, immunohistochemical analyses of ß-catenin and SOX9 are useful to distinguish SCT from other sex cord-stromal tumours of the testis. Furthermore, the presence of SOX9 indicates that the cells of origin may be Sertoli cells.

[Principles of surgery for retroperitoneal sarcoma]. / Chirurgische Therapieprinzipien bei retroperitonealen Sarkomen.

The successful treatment of retroperitoneal soft tissue sarcomas requires an experienced team consisting of not only surgeons but also pathologists and radiologists with a high case load in these tumours. The decisive step in the preoperative work-up of these, often late detected, tumours is their reliable grading as well as, if necessary, recognition of the sarcoma subtype as a basis for determining the direction of treatment. Imaging methods provide essential information with regard to the detection of infiltration of neighbouring structures and organs. Magnetic resonance imaging (MRI) is the most suitable method for this purpose. Punch needle biopsy is to be preferred over fine-needle biopsy in all cases for histological confirmation. The surgical standard procedure for the majority of the patients comprises multivisceral resection as principle, with additional colon resection, nephrectomy, and resection of abdominal wall musculature or, respectively, the psoas muscle in order to achieve an R0 resection of the retroperitoneal compartment. If only small margins of clearance are to be expected, a preoperative (neoadjuvant) treatment with radiation and/or chemotherapy even in combination with deep wave hyperthermia for high grade sarcomas should be strongly considered. Adjuvant postoperative radiation therapy often cannot be adequately applied due to the occupation of the former tumour bed by abdominal organs that were displaced by the mass effect, especially the radiation-sensitive small bowel. The optimal treatment strategy for these patients must be discussed in a multidisciplinary tumour board prior to any diagnostic or therapeutic procedure.

Spongiotic pericytoma: a benign neoplasm deriving from the perisinusoidal (Ito) cells in rat liver.

Spongiosis hepatis has been known for some time to develop frequently in livers of rats and fish treated with hepatocarcinogens and was considered to derive from the perisinusoidal (Ito) cells (PSC). Using rat liver treated with N-nitrosomorpholine at different dose levels, we studied the cellular composition and origin as well as the proliferation kinetics of spongiosis hepatis by immunohistochemical demonstration of desmin, vimentin, and alpha-smooth-muscle actin, and by autoradiographic determination of [3H]-thymidine incorporation, respectively. The vast majority of the cells forming spongiosis hepatis were positive for desmin and vimentin but negative for alpha-smooth-muscle actin, confirming the cellular origin of spongiosis hepatis from PSC. In addition, immunohistochemical demonstration of desmin and vimentin revealed that spongiosis hepatis is an integral part of larger lesions consisting of focal PSC aggregates. These aggregates show a significantly increased incorporation of [3H]-thymidine compared with PSC in the extrafocal tissue and in the liver tissue of untreated control animals. In stop experiments, this increased labeling index was maintained many months after withdrawal of the carcinogen, in line with the earlier observation of a progressive behavior of spongiosis hepatis. We conclude that PSC may give rise to proliferative lesions appearing as PSC aggregates associated with more or less pronounced spongiosis hepatis. The persistence, the proliferative activity, and the slow expansive growth of these lesions suggest a benign neoplastic behavior. We therefore propose to classify these lesions as spongiotic pericytoma. Malignant tumors possibly originating from spongiotic pericytoma should consequently by classified as perisinusoidal (Ito) cell sarcomas.

Streptokinase dissolution of a right atrial thrombus associated with a temporary pacemaker.

Thrombosis of intravascular catheters is a well-recognized and potentially serious complication, which has been treated successfully with thrombolytic agents. A routine echocardiogram in a patient with a temporary transvenous pacemaker demonstrated a large thrombus attached to the pacing electrode. This was dissolved successfully and uneventfully with high-dose intravenous streptokinase therapy. To our knowledge, this is the first report of the successful lysis of a right atrial thrombus complicating a temporary transvenous pacemaker.