Karl Christoph Sproll

Publications of Karl Christoph Sproll

• CT-scan is a valuable tool to detect mandibular involvement in oral cancer patients.

  Authors: Jörg Handschel, Christian Naujoks, Rita A Depprich, Norbert R Kübler, Patric Kröpil, Julia Kuhlemann, Theresa Maria Jansen, Inga Boeck, Karl Christoph Sproll

  Oral oncology. 12/2011;

  In patients with oral squamous cell carcinomas (OSSC) it is desirable to avoid unnecessary bone resection without neglecting the overall surgical treatment goal of tumor-free margins. WhereasIn patients with oral squamous cell carcinomas (OSSC) it is desirable to avoid unnecessary bone resection without neglecting the overall surgical treatment goal of tumor-free margins. Whereas computed tomography (CT) is most commonly used to detect mandibular invasion, there are conflicting reports regarding the accuracy of CT. Therefore, the aim of this study was to reinvestigate the accuracy of CT in predicting mandibular involvement by OSSC. One hundred and seven patients with OSSC who received a mandibulectomy were included. Before treatment all patients underwent a contrast-enhanced multi-detector CT. Axial 3 or 1.25mm thick images were reconstructed for evaluation in overlapping technique and displayed in a bone (1400/400HU) and a soft tissue window (350/50HU). CT scans were examined by three investigators and compared with the histological findings. The radiological examination showed a high interrater reliability (Cronbachs alpha 0.982). Comparing the radiological findings with the histological results the CT showed 8 false-positive results and 8 false-negative patients. The quality criteria for detecting bone involvement of OSSC by CT were calculated as follows: sensitivity 82.6%; specificity 86.9%; positive predictive value 82.6%; negative predictive value 86.9%. However, in all false-positive patients a sagittal bone defect of 15.1mm could be found presumably caused by pressure of the tumor, but no histologically detectable bone infiltration. Modern CT (1-2mm sections) is a valuable tool for surgical treatment planning. If bone invasion is detected, a mandibulectomy seems always reasonable. In radiologically negative cases histological assessment is necessary to detect mandibular involvement.

• Is there a role for the Fas-/Fas-Ligand pathway in chemoresistance of human squamous cell carcinomas of the head and neck (SCCHN)?

  Authors: Karl Christoph Sproll, Hilmar Balló, Thomas K Hoffmann, Kathrin Scheckenbach, Ursula Koldovsky, Vera Balz, Dieter Hafner, Uwe Ramp, Henning Bier

  Oral oncology. 08/2008;

  The aim of the present investigation was to determine the expression of the Fas-receptor/ligand system in established cell lines of squamous cell carcinomas of the head and neck (SCCHN), and to studyThe aim of the present investigation was to determine the expression of the Fas-receptor/ligand system in established cell lines of squamous cell carcinomas of the head and neck (SCCHN), and to study it's functional impact on chemotherapy-induced apoptosis in these SCCHN cell lines. We observed constitutive expression of Fas and FasL in 13 SCCHN cell lines by RT-PCR, Southern-blotting and immunocytochemistry, respectively. Administration of the agonistic Fas-antibody CH-11 led to a significant reduction of viable cells in the colorimetric MTT-assay in 5 out of 13 (38%) cell lines tested and preincubation with Interferon-gamma (IFN-gamma) rendered 3 (23%) primarily resistant cell lines sensitive. Cisplatin (cDDP) and bleomycin (BLM) caused dose-dependent cytotoxicity in all cell lines as determined by the 50% inhibitory concentration (IC(50)) and induction of apoptosis. Furthermore, both antineoplastic agents led to an enhanced surface expression of Fas and FasL in all cell lines, and this effect was independent of the respective p53-status. This upregulation of Fas/FasL surface expression increased preexisting Fas-sensitivity only, but failed to make primarily resistant cell lines undergo Fas-mediated growth reduction or apoptosis. Vice versa, blockade of Fas-receptor-ligand-interactions by monoclonal antibodies directed against FasL was able to attenuate the cytotoxic effect of cDDP and BLM in 2 out of 5 (40%) cell lines tested only. In conclusion, in contrast to many other solid tumors, the Fas/FasL-system does not seem to play an exclusive role in anticancer drug mediated apoptosis in SCCHN.

• Nonvascularized iliac bone grafts for mandibular reconstruction--requirements and limitations.

  Authors: Jörg Handschel, Hirama Hassanyar, Rita A Depprich, Michelle A Ommerborn, Karl Christoph Sproll, Matthias Hofer, Norbert R Kübler, Christian Naujoks

  In vivo (Athens, Greece). 25(5):795-9.

  Treatment of intraoral malignant tumors often leads to continuity defects of the mandible. Whereas the use of free vascularised flaps has shortcomings regarding donor site morbidity and aTreatment of intraoral malignant tumors often leads to continuity defects of the mandible. Whereas the use of free vascularised flaps has shortcomings regarding donor site morbidity and a worse-fitting bone geometry, the nonvascularized iliac crest graft could be an alternative option. The purpose of this study was to describe the treatment outcome with nonvascularized iliac crest grafts over a 10-year period and to determine possible limitations of their use. Eighty-four patients with bicortical nonvascularized iliac crest grafts for mandibular reconstruction were examined at least one year after reconstruction. Patients' records and the radiological and/or surgical data were analyzed. Sixty-three patients (75%) showed complete healing, in 20 patients the treatment was not successful and in one patient the treatment result was unclear. Interestingly, comparing the successfully and the unsuccessfully treated patients, only the irradiation dose played a crucial role. Neither defect length nor defect localisation, nor time interval between resection and reconstruction were statistically significant parameters in graft success. Comparing only patients with malignancies, the non-irradiated patients had a higher success rate (77.3%). The nonvaslcularized iliac crest graft seems to be a reasonably reliable treatment option for reconstruction of mandibular defects up to about 5-6 cm in size. Radiotherapy is a strong confounder reducing the success rate. Necessary constraints are sufficient soft tissue conditions. However, primary reconstruction by free flaps (e.g. fibula flap) has a higher success rate in literature and should be preferred whenever possible.