Altered mRNA expression of glycosyltransferases in human colorectal carcinomas and liver metastases

BACKGROUND/AIMS

Biosynthesis of carbohydrate structures is tissue specific and developmentally regulated by glycosyltransferases such as fucosyltransferases, sialyltransferases, and N-acetylgluco- saminyltransferases. During carcinogenesis, aberrant glycosylation leads to the development of tumour subpopulations with different adhesion properties. Therefore alterations in glycosyltransferase mRNA expression in colorectal carcinomas were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR).

METHODS

Colorectal carcinoma specimens were classified and characterised according to the WHO/UICC system. Expression of fucosyltransferases FT-I, FT-III, FT-IV, FT-V, FT-VI, and FT-VII, sialyltransferases ST3Gal-I, ST3Gal-III, ST3Gal-IV, and ST6Gal-I, beta1,4-galacto- syltransferase, and beta1,6-Nacetylgluco- saminyltransferase V (GNT-V) was screened simultaneously in extracts of 22 homogenised tumour specimens by RT-PCR and compared with corresponding mucosa from each patient. Also 12 adenomas and 17 liver metastases of colorectal carcinomas were examined.

RESULTS

GNT-V expression was enhanced in colorectal adenomas (p = 0.039), carcinomas (p<0.001), and liver metastases of colorectal carcinomas (p<0.001). Also, expression of fucosyltransferase FT-IV was increased in colorectal adenomas (p = 0.039) and carcinomas (p<0. 001). In addition, fucosyltransferase FT-I (p<0.001) and sialyltransferases ST6Gal-I (p = 0.004) and ST3Gal-III (p = 0.001) showed increased expression in carcinoma specimens. On the other hand, fucosyltransferase FT-III was less abundantly expressed in carcinomas exhibiting distant metastases (p = 0.046) and in highly invasive tumours (p = 0.041).

CONCLUSIONS

Glycosyltransferase mRNA expression is significantly altered in colorectal adenomas and carcinomas isolated from surgical specimens. RT-PCR determination of specific glycosyltransferases may be helpful for earlier detection of carcinomas and for tumour prognosis.

Three-dimensional ultrasonography: new prospects for ultrasound imaging of bone

Radiography is used for the initial evaluation of suspected bone lesions. We have shown that surface images of bone can be obtained by three-dimensional ultrasonography.

Fluorescence as a concept in colorectal lymph node diagnosis

Fluorescence detection may constitute an appropriate means in gastrointestinal cancers to diagnose lymphatic tumor spread as opposed to gamma-scintillation methods. Photodiagnostic tracers have been shown to localize rapidly in malignant cells and may enable sensitive detection of small cell aggregates in lymph nodes. To reach a detection depth of several millimeters, a broad banded unspecific tissue autofluorescence may be controlled by so-called background subtracting techniques, generally based either on fluorescence observation at several wavelengths or on dual-wavelength fluorescence excitation. Using such comparative fluorescence detection techniques, some tumor entities can be differentiated soley based upon autofluorescence characteristics. Introducing a further enhancement in sensitivity for longer life-time fluorophores by time delayed fluorescence detection we ran a pilot trial comprising 174 lymph nodes from colorectal cancer specimen from 9 patients. Metastatically involved lymph nodes could be differentiated from all other palpable nodes in the mesenteric fat at a specificity of 85% with a sensitivity of 65%. Specific fluorescence features may be useful to preselect tissue samples for further histological analysis.

Sentinel lymph node dissection in breast cancer

During the last years, the efficacy and reliability of the sentinel lymph node biopsy (snb) as a minimal invasive diagnostic procedure for the nodal status has been intensively evaluated. After the widespread clinical use in the staging of melanoma patients the snb is currently introduced in the clinical management of breast cancer patients. We present our experience with this method during 3, 5 years and discuss its potential and pitfalls. From 11/95 to 3/99 we performed sentinel node detection in 146 patients with breast cancer stage I to III, consisting of 127 patients with pT1/2-tumors and 19 patients with pT3/4-tumors. We used the radionuclid method including preoperative lymphoscintigraphy and intraoperative gamma-probe detection. The detection rate varied with the tumor size between 94% for tumors with a diameter < 1 cm, 85% (1-3 cm), 70% (3-5 cm) and 63% (> 5 cm). The accuracy of the snb in the prediction of the nodal status changed also with the tumor diameter between 100% for very small tumors (< 1 cm), 97% (1-3 cm), 88% (3-5 cm) and 67% (> 5 cm). In the subgroup of patients restricted to T1-2-tumors (n = 106). 57 patients (53%) showed true negative snb. 38 patients (36%) revealed tumor cells in the H&E-staining and an additional 7 patients (7%) solely in the immunohistochemical staining. 4 (4%) of these patients, all of them from the first half of the study period, underwent false-negative snb, 3 of them showing lymphangiosis carcinomatosa. The presented results show, that snb using the radionuclid method is a reliable method for the evaluation of the nodal status in early breast cancer patients with a tumor size up to ca. 3 cm. Therefore the sn procedure should be restricted to small tumors with clinically uninvolved axillary nodes or patients with a ductal carcinoma in situ (DCIS) to rule out invasiveness.

Telemedicine: the new must for surgery

The vision of telesurgery comprises a multitude of new communicative elements influencing the way surgeons will treat their patients in the future. The first prerequisite for effective telecommunication is to digitize surgical data. Many medical imaging modalities provide primarily digital data sets, and digital image communication is already entering clinical practice under the labels of teleradiology and telepathology. However, for any surgical purpose, images must refer to tissues. Three-dimensional image reconstruction is warranted, and if such data shall be useful during surgery, different image sources must be combined into some virtual, multiparametric body model and matched to an intraoperatively distorted organ contour. A multitude of detail problems arise, beginning with image standards, data interfaces, data transport, image fusion, registering, contour matching, and, once the data are integrated, all the aspects of surgery-suitable data display and interaction. We refer here to several demonstration projects illustrating such a complex surgical data set and its interactive telecommunication. In all instances, telecommunication was to enable a concentration of distributed medical intelligence at the site where the patient was treated. With further technological development, such telesurgical applications will have a growing influence on patient management and surgical decision making. In the very near future, computer-aided navigation and robotic assistance, based on the same surgical data sets, will be available to all fields of surgery. How decisive the role these methods will play for specific procedures or diseases needs to be determined.

EUS-guided fine needle biopsy: minimally invasive access to metastatic or recurrent cancer

OBJECTIVE

Endoscopic ultrasound (EUS) is a sensitive technique for preoperative staging of gastrointestinal tumors. However, the value of this technique in the diagnosis of metastatic or recurrent disease is limited by the inability to differentiate malignant and benign lesions. We have prospectively investigated the role of EUS-guided biopsy in the evaluation of peri-intestinal tumors.

METHODS

EUS-guided biopsy was performed in 167 patients with thoracic, intra-abdominal or pelvic lesions. The upper gastrointestinal tract was examined with a flexible echoendoscope equipped with a 7.5 MHz curved array transducer. For transrectal EUS a rigid endoprobe with a bifocal multiplane transducer (10 MHz) was used. Both instruments allowed to observe the biopsy procedure exactly in the longitudinal scan plane.

RESULTS

Real time ultrasonography guidance of the biopsy needle enabled precise tissue sampling even of small lesions with a diameter of 1 cm. Overall EUS-guided fine needle biopsy yielded tissue samples for histopathologic or cytologic analysis in of 151 of 167 patients. Histology demonstrated benign lesions in 71 of 74 patients and malignant tumors in 68 of 93 patients. EUS-guided fine needle biopsy failed to provide the correct diagnosis in 28 cases. The overall sensitivity and specificity of EUS-guided biopsy in the diagnosis of malignancy were 73 and 96%, respectively. The histopathological results changed the clinical and endosonographic diagnosis in 49 patients. No complications were observed related to the biopsy.

CONCLUSIONS

EUS-guided needle biopsy is a safe and efficient method for tissue sampling of peri-intestinal lesions. This minimally invasive technique provides adequate biopsies and improves the diagnostic value of endoscopic ultrasonography considerably.

Accuracy of endorectal ultrasound after preoperative radiochemotherapy in locally advanced rectal cancer

OBJECTIVES

Factors limiting the accuracy of endorectal ultrasound in staging, locally advanced primary rectal cancer after preoperative neoadjuvant radiochemotherapy (RCT) were evaluated.

METHODS

Patients (n = 84) with initial locally advanced rectal cancer (uT3/uT4) undergoing R0 resection were investigated after preoperative treatment that combined radiotherapy up to 45 Gy with two cycles of chemotherapy (5-FU and leucovorin on d 1-5 and 22-28). At 4 to 6 weeks after completion of RCT and before tumor resection, preoperative endoluminal ultrasound was performed.

RESULTS

The accuracy to predict the depth of tumor infiltration (T-category) was found to correlate with downstaging. The T-category was correctly staged before surgery in 15 of the 51 responders (29%) and in 27 of 33 nonresponders (82%), whereas misinterpretation occurred in 36 of the responders (71%) and in 6 of the nonresponders (18%) (p < 0.001). Neither tumor distance from anal verge nor tumor location correlated with the staging accuracy. Lymph node involvement was correctly assessed in 48 patients (57%). Wall invasion was correctly ascertained in 42 patients (50%), with under estimation in 11 patients (13%) and overestimation in 31 patients (37%).

CONCLUSIONS

After radiochemotherapy, endosonography does not provide a satisfactory accuracy for preoperative staging of rectal cancer. New interpretation and diagnostic criteria are needed for the prediction of treatment response.

Intravenous administration of recombinant adenoviruses causes thrombocytopenia, anemia and erythroblastosis in rabbits

BACKGROUND

Recombinant adenoviruses are highly efficient gene transfer vehicles but their administration to mammals is accompanied by a strong inflammatory response. The present study reports additional side effects observed during adenoviral gene transfer studies in rabbits.

METHODS

Hematological and serological parameters, the course of viremia and the organ distribution were analyzed after in vivo administration of E1-deleted adenoviruses in rabbits.

RESULTS

The systemic administration of a therapeutic dose of 5 x 10(11) infectious particles/kg (infusion time 20 min) led to an average reduction of 80-90% in the platelet count within 48 h. Full recovery took 10-14 days. Virus administration induced a strong but transient erythroblastosis (peaking 24 h after administration) which settled 48 h later. Normochromic anemia occurred over the next 10 days with hemoglobin levels dropping by about 40% to reach the lowest level 10 days after administration and taking two months for full recovery. Dose-dependent thrombocytopenia was also found in mice, but neither erythroblastosis nor anemia was observed (in equivalent doses). The hematological findings did not improve after local injection via the portal vein. Local and systemic administration led to a comparable course of viremia. Only minor differences were found in the biodistribution of viruses between local and systemic administration. Large amounts of viral DNA and transgene expression were found in the lungs, the kidneys and the ovaries, even after local administration via the portal vein.

CONCLUSIONS

Local intravenous injection via the portal vein does not prevent systemic spread of viral vectors and the occurrence of vector-related side effects. The hematological changes observed in rabbits suggest the need for careful monitoring of hematological and rheological parameters in clinical trials.

Microsatellite alterations in serum DNA of patients with colorectal cancer

Cell-free DNA in the blood of cancer patients has been shown to harbor microsatellite alterations frequently matching those of the primary tumors. The aim of this study was to assess the prevalence of allelic loss and instability of serum DNA microsatellites in colorectal cancers. DNA extracted from preoperative sera and microdissected tumors of 27 patients with colorectal adenocarcinoma were allelotyped for nine markers on chromosome arms 1p, 5q, 8p, 12p, 15q, 17p, 17q, and 18q. In all tumors, expression of MLH1 and MSH2 was explored immunohistochemically. Microsatellite alterations comprising loss of heterozygosity (LOH) or microsatellite instability (MSI) were present in 26 of 27 (96%) tumors and in 16 of 27 (59%) serum samples. Using stringent criteria, serum MSI was significantly (p < 0.02) more detectable than serum LOH. Of the three patients with high-grade MSI (more than two unstable loci) present in tumor and serum DNA, two had MSH2-negative tumors on immunohistochemical testing. No significant association of tumor stage or clinical outcome with serum microsatellite alterations of LOH or MSI type could be demonstrated. Although the DNA-shedding phenotype of tumors remains to be elucidated, its detection by serum DNA microsatellite analysis seems to be useful for the diagnosis and monitoring of neoplasms, including colorectal cancers with and without MSI.

Three-dimensional endoluminal ultrasound: a new method for the evaluation of gastrointestinal tumors

BACKGROUND

The purpose of the present study was to evaluate the feasibility of three-dimensional endoluminal ultrasound of gastrointestinal tumors.

METHODS

Sixteen patients with esophageal, gastric, or colorectal tumors underwent endoscopic ultrasound. Three-dimensional ultrasound data were obtained from multiple serial images of a miniprobe (360 degrees, 12.5 MHz) and processed on a PC-based 3D workstation.

RESULTS

Adequate three-dimensional ultrasound scans were obtained in eight patients with esophageal cancer and five patients with colorectal cancer. Three-dimensional image processing enabled visualization of the data as a multiplanar display or as a life-like three-dimensional view. The availability of arbitrary scan planes improved the assessment of local tumor spread and the spatial relation of the tumor to relevant adjacent structures (e.g., major vessels). Three-dimensional presentations provided realistic views of the anatomy and facilitated the interpretation of the ultrasound images.

CONCLUSIONS

Three-dimensional display and the ability to review endoluminal ultrasound data interactively may improve the staging of gastrointestinal tumors. These preliminary data encourage further evaluation of this technique.

Altered mRNA expression of glycosyltransferases in human gastric carcinomas

Biosynthesis of carbohydrate structures is tissue-specific and developmentally regulated by glycosyltransferases like fucosyl-, sialyl- and N-acetylglucosaminyltransferases. During carcinogenesis, aberrant glycosylation leads to the development of tumor subpopulations with different adhesion properties. The aim of this contribution was to directly compare mRNA expression of several glycosyltransferases in surgical specimens of gastric carcinomas. Carcinoma specimens were classified and characterized according to the WHO/UICC system. In each case, the expression of 12 glycosyltransferase enzymes was studied simultaneously by RT-PCR. For semi-quantitative analysis, amplification of the sample sequence was compared with that of beta-actin, co-amplified within the same tube. Expression of N-acetylglucosaminyltransferase V in gastric carcinomas was significantly enhanced compared to normal tissue. Also, expression of sialyltransferase ST3Gal-IV and fucosyltransferase FT-IV was significantly enhanced in carcinoma tissue. No significant differences in glycosyltransferase expression were found in samples positive for Helicobacter pylori or between the different gastric regions. Thus, carcinogenesis is characterized by specific alterations in mRNA expression of several glycosyltransferases. Future studies will show whether RT-PCR detection of the expression of these enzymes could be helpful for prognostic purposes.

[Preoperative classification of malignant stomach tumors]

Based on the case report of a 51 year-old patient presenting with a lymphoepithelioma like gastric cancer, we discuss the diagnostic challenge to differentiate this entity from gastric non-Hodgkin lymphoma. Since high-level lymphoid stromal reactions are rarely associated with gastric adenocarcinoma, misinterpretation can occur easily. In addition to the lymphoepithelioma like gastric cancer that is often associated with a demonstrable EBV association of the tumor cells, synchronous development of gastric carcinoma and lymphoma must be considered. Establishment of a correct diagnosis requires multiple, deep and multifocally sampled gastric biopsies, and immunohistochemical and molecular techniques to supplement conventional histology. Only through this procedure are correct characterization and classification of these unusual gastric neoplasms possible.

[Foreign body-induced thoracic actinomycosis as differential mediastinal space-occupying lesion diagnosis]

Thoracic actinomycosis is a rare disease often mistaken for malignancy. Untreated actinomycosis is associated with high mortality, the disease should, thus, be considered early. We report the case of a 58-year-old male patient who was referred to us for a suspected thoracic sarcoma. He had 6-month a history of hemoptysis, and there was severe deterioration in his general health. Only in a roundabout way was the diagnosis of thoracic actinomycosis established; it was caused by an aspirated chicken bone, as found by bronchoscopy. All symptoms rapidly regressed by antibiotic therapy and definitive healing was obtained. In the diagnostic work up of thoracic masses that may represent inflammatory diseases, lymphoma, thymus-associated, sarcomatous and germ-cell tumors, bronchoscopy is of primary diagnostic importance.

A rare malformation of the pancreaticobiliary junction long common channel choledochal cyst and pancreas divisum in a patient with pancreatic cancer

Congenital variants of the pancreaticobiliary junction are rare anomalies that are usually diagnosed in childhood because of recurrent abdominal pain and jaundice. These lesions are associated with several pancreaticobiliary diseases including pancreatitis and malignancy. We observed a rare anomaly of the pancreaticobiliary tract with a combination of several ductal malformations, i.e., choledochal cyst, long common channel and incomplete pancreas divisum in a patient with pancreatic cancer.

Development of a time-domain optical mammograph and first in vivo applications

We have developed a laser-pulse mammograph capable of recording optical mammograms within approximately 3 min by measuring time-resolved transmittance at each of typically 1500 scan positions, 2.5 mm apart. As a first application two patients who have tumors were investigated successfully. From measured distributions of times of flight of photons corrected for edge effects we derived (1) characteristic quantities, such as photon counts in selected time windows, to generate optical mammograms; (2) effective transport scattering and absorption coefficients of breast tissue at each scan position, assuming the breast to be homogeneous; and (3) optical properties of a selected tumor by applying the theory of diffraction of photon density waves by spherical inhomogeneity. Mammograms recorded at different lateral offsets between source and detector fiber were used to estimate the depth of inhomogeneities.

GLI gene expression in bone and soft tissue sarcomas of adult patients correlates with tumor grade

The GLI gene encodes a transcription factor harboring five zinc finger motifs that bind to DNA in a sequence-specific manner. The gene was originally identified because of its amplification in a human glioblastoma, and previous studies have shown it to be amplified in a significant proportion of mesenchymal tumors, such as childhood sarcomas. Here we evaluate GLI gene expression in bone and soft tissue sarcomas of adult patients. Samples from 40 patients (37 sarcomas and 3 benign mesenchymal tumors) and samples of 15 normal mesenchymal tissues were examined for GLI gene amplification and expression by Southern hybridization, reverse transcription-PCR of tissue RNA, and immunohistochemistry, using a new polyclonal GLI antibody developed against an epitope outside of the zinc finger region. In contrast to childhood sarcomas, amplification of the GLI gene was not observed in sarcomas of adult patients. Although GLI gene expression in sarcomas was significantly higher than that in normal mesenchymal tissues (P < 0.0001), the levels were very variable. Attempts to correlate the expression data with different pathophysiological parameters only showed a significant relationship to tumor grade. Based on these data, increased levels of GLI gene expression may be indicative of the aggressiveness of the tumor.

Preoperative treatment of rectal cancer with radiation, chemotherapy and hyperthermia: analysis of treatment efficacy and heat-shock response

Preoperative treatment of locally advanced rectal cancer with radiation, chemotherapy and hyperthermia is analyzed with regard to heat-shock response. In 23 patients with locally advanced rectal cancer (uT3/uT4), hyperthermia was administered in combination with radiotherapy and chemotherapy. In parallel, the effect of the treatment on levels of the heat-shock proteins HSP27 and inducible HSP70 in tumors and surrounding tissues was investigated by Western blotting. The patients' sera were also examined for autoantibodies against HSPs. HSP27 and inducible HSP70 were detected in most rectal tumors and surrounding tissues before and after treatment. HSP27 and inducible HSP70 levels had changed in 10 tumors after treatment. However, prior to treatment, there existed an unexpected diversity in HSP levels in the tumors and surrounding tissue. Hyperthermia doses in cumulative minutes for which 90% of the tumor is above the reference temperature (cum min T90 > or = 15 min) led to increased survival and response compared to that of a control group of patients treated without or with low-dose hyperthermia (cum min T90 < 15 min). However, there was no correlation to different expression of the HSPs. Hyperthermia as used in this setting does not lead to any sustained expression of HSPs in either the tumor or the surrounding tissue.

[Determinants for operative and multimodal treatment of malignant soft tissue tumors]

An optimal treatment of soft tissue sarcomas is influenced by multiple factors. An improvement of the still unfavourable prognosis for some patients with soft tissue sarcomas with a high local recurrence rate, oftly based on an inadequate surgical primary therapy, can be achieved only if guidelines described in this paper gain increasing influence in practice. The treatment concept for malignant soft tissue sarcomas must be worked out a priori interdisciplinary after knowledge of all relevant dates and findings. Surgery is here only one, but at the right time an essential component of therapy. The R0 resection is an important requirement for a freedom of local recurrence, but the influence of a local recurrence on overall survival remains controversial. Therefore amputations should be taken into consideration only after exhaustion of all available procedures.

[Molecular biology of breast carcinoma. Current diagnostic, therapeutic and prognostic aspects]

There has been a huge progress in our understanding of the genetic mechanisms involved in the development of breast cancer. The clinical consequences are however still small. The most important theoretical models for future clinical investigation, as well as the practical consequences of the already known facts are discussed.

[Sentinel lymph node detection in patients with breast carcinoma]

Sentinel node detection enables the definition of the most relevant draining lymph node of a tumor. We analysed 123 patients with breast cancer according to this method. A preoperative lymphoscintigraphy was performed 17 hours after a peritumoral application of 0.5 ml 99mTC-Nanokoll. The sentinel node was identified by means of a gammaprobe in 75 of 89 patients with pT1- and pT2-tumors and in 11 of 17 patients with pT3-4 tumors respectively. The results of histological investigation of the sentinel node in comparison to all other axillary nodes following dissection were correlated. In the pT1-2 group the accuracy of correlative findings was rather high (96%). In patients with pT3- and pT4-tumors the lymph node status was predictable only in 7 patients. Therefore sentinel node biopsy may serve as a tool for individualization of axillary dissection especially in pT1-2 breast cancer patients.

Results of surgery and multimodal therapy for patients with soft tissue sarcoma invading to vascular structures

BACKGROUND

The aim of this study was to analyze the impact of resection and reconstruction of major vessels on the limb salvage rate, local disease free survival, and overall survival for patients with soft tissue sarcomas invading to neurovascular bundles.

METHODS

Twenty patients were treated in a 7-year period by one surgical team. Preoperative therapy consisted of isolated limb perfusion (n = 6), systemic chemotherapy (n = 4), systemic chemotherapy combined with regional hyperthermia (n = 2), and external beam irradiation (n = 1). All patients underwent resection of the sarcoma monobloc together with the neurovascular bundle invaded. Vessels were replaced by an autologous vein transplant or an allograft, and, in six patients, a myocutaneous flap or skin graft had to be used for soft tissue coverage.

RESULTS

Histologic examination revealed negative histologic margins (R0-resection) and infiltration of the neurovascular bundle in all patients. In four patients, a local recurrence was observed, and, in three of them, reresection with negative margins was achieved. The mean local recurrence free survival was 54 months (confidence interval [CI], 42-66 months), and the mean overall survival was 48 months (CI, 32-57 months). Limb salvage was achieved in 19 of 20 patients. Eleven patients developed distant metastases after a mean survival time of 30 months.

CONCLUSIONS

Extended sarcoma resection, including vessel replacement after preoperative multimodal therapy, provides long term local control and limb salvage. Amputation of extremity sarcoma can hardly be justified, even in cases of tumor invasion to neurovascular bundles. However, efforts to achieve better control over systemic spread are required for long term disease free survival.