Is mesh pore size in polypropylene meshes associated with the outcome in Lichtenstein inguinal hernia repair: a registry-based analysis of 22,141 patients

INTRODUCTION

Experimental data show that large-pored meshes reduce foreign body reaction, inflammation and scar bridging and thus improve mesh integration. However, clinical data on the effect of mesh porosity on the outcome of hernioplasty are limited. This study investigated the relation of pore size in polypropylene meshes to the outcome of Lichtenstein inguinal hernioplasty using data from the Herniamed registry.

METHODS

This analysis of data from the Herniamed registry evaluated perioperative and 1-year follow-up outcomes in patients undergoing elective, primary, unilateral Lichtenstein inguinal hernia repair using polypropylene meshes. Patients operated with a non-polypropylene mesh or a polypropylene mesh with absorbable components were excluded. Polypropylene meshes with a pore size of 1.0 × 1.0 mm or less were defined as small-pored meshes, while a pore size of more than 1.0 × 1.0 mm was considered large-pored. Unadjusted analyses and multivariable analyses were performed to investigate the relation of pore size of polypropylene meshes, patient and surgical characteristics to the outcome parameters.

RESULTS

Data from 22,141 patients were analyzed, of which 6853 (31%) were operated on with a small-pore polypropylene mesh and 15,288 (69%) with a large-pore polypropylene mesh. No association of mesh pore size with intraoperative, general or postoperative complications, recurrence rate or pain requiring treatment was found at 1-year follow-up. A lower risk of complication-related reoperation tended to be associated with small-pore size (p = 0.086). Furthermore, small-pore mesh repair was associated with a lower risk of pain at rest and pain on exertion at 1-year follow-up.

CONCLUSION

The present study could not demonstrate an advantage of large-pore polypropylene meshes for the outcome of Lichtenstein inguinal hernioplasty.

[Effects of new minimum volume standards in visceral surgery on healthcare in Brandenburg, Germany, from the perspective of healthcare providers]

BACKGROUND

The legally prescribed minimum volume standards for complex esophageal and pancreatic surgery have been increased or will increase in 2023 and 2025, respectively. Hospitals not reaching the minimum volume standards are no longer allowed to perform these surgeries and are not entitled tor reimbursement.

OBJECTIVE

The study aims to explore which effects are expected by healthcare professionals and patient representatives and what possible solutions exist for Brandenburg, a rural federal state in northeast Germany.

MATERIAL AND METHODS

In this study 19 expert interviews were conducted with hospital employees (head/senior physicians, nursing director), resident physicians and patient representatives between July 2022 and January 2023. The data analysis was based on content analysis.

RESULTS

Healthcare professionals and patient representatives expect a redistribution into a few clinics for surgical care (specialized centres); conversely more clinics that do not (no longer) perform the defined surgeries but could function as gatekeeping hospitals for basic care, diagnostics and follow-up (regional centres). The redistribution could also impact forms of treatment that are not directly defined within the regulation for minimum volume standards. The increased thresholds could also affect medical training and staff recruitment. A solution could be collaborations between different hospitals, which would have to be structurally promoted.

CONCLUSION

The study showed that minimum volume standards not only influence the quality of outcomes and accessibility but also have a multitude of other effects. Particularly for rural regions, minimum volume standards are challenging for access to esophageal and pancreatic surgery as well as for communication between specialized and regional centres or resident providers.

[Epidemiology and surgical treatment of pancreatic cancer in the State of Brandenburg : Analysis of 5418 cases]

BACKGROUND

Pancreatic cancer is the second most frequent cause of death among all forms of cancer in Germany with more than 19,000 deaths per year. The evaluation of the nationwide clinical cancer register aims to depict the reality of treatment and to improve the quality of treatment in the future by targeted analyses.

METHOD

The data from the clinical cancer register of Brandenburg-Berlin for the diagnosis years 2001-2017 were analyzed with respect to the treatment of pancreatic cancer. Data from patients resident in the State of Brandenburg were evaluated with respect to epidemiological and therapeutic parameters.

RESULTS

A total of 5418 patients with pancreatic cancer were documented in the register from 2001 to 2017 and 49.6% of the patients were diagnosed as having the Union for International Cancer Control (UICC) stage IV. A pancreas resection was carried out in 26.4% of the cases. In cases of cancer of the head of the pancreas the most frequent procedure was a pylorus-preserving resection with 51.8% and a pancreatectomy was carried out in 9.4%. The R0 resection rate of all pancreatic cancers in the period from 2014 to 2017 was 61.9%. After R0 resection the 5‑year survival was 19%. Relevant multivariate survival factors were age, UICC stage and the residual (R) tumor classification. The case numbers per hospital had no influence on the absolute survival of patients operated on in the State of Brandenburg.

CONCLUSION

The treatment reality in the State of Brandenburg for patients with pancreatic cancer corresponds to the results of international publications with respect to the key performance indicators investigated. A qualitative internationally comparable treatment of these patients is also possible in nonmetropolitan regions.

Outcome of inguinal hernia repair after previous radical prostatectomy: a registry-based analysis with 12,465 patients

INTRODUCTION

Following radical prostatectomy, the rate of inguinal hernias is fourfold higher compared to controls. Laparo-endoscopic repair after previous radical prostatectomy is considered complex. Therefore, the guidelines recommend open Lichtenstein repair. To date, there are limited data on inguinal hernia repair after prior prostatectomy.

METHODS

In a retrospective analysis from the Herniamed Registry, the outcomes of 255,182 primary elective unilateral inguinal hernia repairs were compared with those of 12,465 patients with previous radical prostatectomy in relation to the surgical technique. Furthermore, the outcomes of laparo-endoscopic versus open Lichtenstein repair techniques in the 12,465 patients after previous radical prostatectomy were directly compared.

RESULTS

Comparison of the perioperative complication rates for primary elective unilateral inguinal hernia repair with and without previous radical prostatectomy demonstrated for the laparo-endoscopic techniques significantly higher intraoperative complications (2.1% vs 0.9%; p < 0.001), postoperative complications (3.2% vs 1.9%; p < 0.001) and complication-related reoperations (1.1% vs 0.7%; p = 0.0442) to the disadvantage of previous prostatectomy. No significant differences were identified for Lichtenstein repair. Direct comparison of the laparo-endoscopic with the open Lichtenstein technique for inguinal hernia repair after previous radical prostatectomy revealed significantly more intraoperative complications for TEP and TAPP (2.1% vs 0.6%; p < 0.001), but more postoperative complications (4.8% vs 3.2%; p < 0.001) and complication-related reoperations (1.8% vs 1.1%; p = 0.003) for open Lichtenstein repair.

CONCLUSION

Since there are no clear advantages for the laparo-endoscopic vs the open Lichtenstein technique in inguinal hernia repair after previous radical prostatectomy, the surgeon can opt for one or the other technique in accordance with their experience.

A significant vascular variant in oncologic pancreaticoduodenectomy: the arc of Buhler

Background

The arc of Buhler (AOB), a rare anastomosis connecting the superior mesenteric artery (SMA) to the celiac trunk (CA), was found in a patient suffering from an adenocarcinoma of the pancreatic head.

Case presentation

Oncologic pancreaticoduodenectomy required resection of the AOB to achieve complete tumor removal. After an uneventful clinical course in the first days, the patient suffered a severe complication. Due to ischemia of the stomach and spleen, complete resection of the stomach, spleen, and remaining pancreas had to be performed.

Conclusions

The hemodynamic impact of this arterial variant has been discussed mainly for liver perfusion, which remained intact at all times in our case. Because of the serious obstacles mentioned above, we strongly recommend that the presence of AOB be considered in preoperative diagnosis and preservation when possible. If the AOB is likely to be ligated, stenosis of the SMA or CA should be excluded and resolved before surgery.

External Negative Pressure Drainage of the Pancreatic Duct in Pancreatogastrostomy Following Pylorus-Preserving Pancreaticoduodenectomy-Feasibility and Technique

Background: Postoperative pancreatic fistula (POPF) is a major cause of morbidity after pancreaticoduodenectomy. There is no consensus on the best technique to protect the pancreato-enteric anastomosis and reduce the rate of POPF. This study investigated the feasibility and efficiency of external suction drainage of the pancreatic duct to improve the healing of pancreaticogastrostomy. Methods: Between July 2019 and June 2021, 21 consecutive patients undergoing elective pancreaticoduodenectomy were included. In all patients we performed a pancreaticogastrostomy and inserted a negative pressure drainage into the pancreatic duct. The length and diameter of the pancreatic duct were measured and the texture of the pancreas was evaluated. The daily secretion volume and the lipase value via pancreatic duct drainage were documented. The occurrence of POPF was evaluated. Results: None of the patients had drainage-related complications. In 4 patients we registered a dislocation of the drainage from the pancreas duct into the stomach. 17/21 Patients showed no signs of POPF. A biochemical leak was measured in one patient. Furthermore, 2 patients had a POPF grade B. In one patient, POPF grade C required reoperation and resection of the remnant pancreas. All 4 cases of POPF met the risk criteria soft pancreas, high volume and high lipase value in the duct drainage. Conclusion: The insertion of the pancreatic duct drainage was feasible and caused no drainage-related morbidity. POPF-rate was moderate in the risk population of soft pancreas and small duct.

Laparoscopic sphincter reconstruction after abdominoperineal resection: feasibility and technical aspects

BACKGROUND

Abdominal colostomy has been reported as an option with good quality of life for patients requiring abdominoperineal resection (APR) for very low rectal cancer. Some young, compliant patients, nevertheless, are very motivated to avoid abdominal colostomy following APR. Spiral smooth muscle cuff perineal colostomy as neosphincter reconstruction can be a reasonable alternative. We have published before the results of a series of sphincter reconstruction in the conventional technique following APR. As we developed our technique for colorectal resection sphincter reconstruction, we also changed to a laparoscopic approach.
 The aim of the present study was to evaluate the feasibility of laparoscopic neosphincteric reconstruction and outline the aspects of the technique.

METHODS

This retrospective study was conducted on 15 patients treated at our institution during a 6 year period for low rectal cancer by laparoscopic APR and spiral smooth muscle cuff perineal colostomy as sphincter reconstruction. At follow-up at a median time of 3.7 years (range 3-9 years) after surgery, patients underwent functional evaluation which included the modified Holschneider continence score (0-16), assessing consistency of stool, frequency, impulse, discrimination, warning period, incontinence for formed or fluid feces, soiling, wearing pads, drugs, enema where a score of 13-16 is associated with normal continence, as well as neosphincter manometry.

RESULTS

Laparoscopic sphincter reconstruction was feasible in all 15 patients. Two of the fifteen patients (13%) required secondary colostomy in the long term due to neosphincter malfunction and neosphincter perforation after enema. Four of the remaining thirteen patients (30%) were partially continent according to the Holschneider continence score (HCS) with a score of 7-12. The other 9 (70%) were continent (HCS: 13-16). Neosphincter manometry showed a median resting pressure of 33 cm H₂O (range 30-41 cm H₂O) and a median squeeze pressure of 95 cm H₂O (range 84-150 cm H₂O).

CONCLUSIONS

Laparoscopic sphincter reconstruction following APR is a feasible option offering an alternative to abdominal colostomy for selected patients.

[Risk factors for the development of lymphatic fistula after ilioinguinal lymph node dissection before isolated limb perfusion and its potential clinical relevance]

INTRODUCTION

After ilioinguinal radical lymph node dissection (RLND), the therapy for lymph fistulas constitutes a challenge. Risk factors for the genesis of lymph fistulas have not been sufficiently evaluated. We investigated possible factors that could influence the development of lymph fistulas in patients suffering from malignant melanoma after iloinguinal RLND.

PATIENT AND METHODS

The analysis was related to patients with intransit and lymphonodal metastasised malignant melanoma of the lower limb, who underwent RLND and isolated limb perfusion (ILP). Prospective data acquisition from patients undergoing ilioinguinal RLND and ILP in a one-step approach was performed. The association of lymph fistulas to risk factors was calculated using chi-squared, linear-by-linear test and ROC curves. As possible risk factors we investigated the presence of prior surgery and diabetes mellitus type II in the medical history, chemotherapeutics, patient age and the body mass index (BMI).

RESULTS

Postoperative lymph fistula occurred in 11 of 108 patients (10.2%). A significant association to lymph fistulas was found in BMI (30.2± 7.0 kg/m (2), p<0.02). Other parameters, such as prior surgery (82% vs. 71%), diabetes mellitus type II (9% vs. 11.7%), chemotherapeutics and patient age (mean 67.8 vs. 62.4 years) showed no influence.

CONCLUSION

Our results indicate that the incidence of lymph fistulas after RLND and ILP of malignant melanoma of the lower limb was associated with an increased BMI. Thus, for the prevention of lymph fistulae, an initially alternative wound-closure dressing like vacuum assisted closure (V.A.C.) dressing could be of clinical relevance for obese patients.

Treatment of oesophageal anastomotic leaks by temporary stenting with self-expanding plastic stents

BACKGROUND

Oesophageal anastomotic leakage is associated with considerable morbidity and mortality. The aim of the present study was to assess the feasibility of using temporary self-expanding plastic stents to treat postoperative oesophageal leaks.

METHODS

Patients with anastomotic leakage after abdominothoracic oesophagectomy treated by endoscopic insertion of self-expanding plastic stents between 2001 and 2007 were studied. Clinical outcomes were analysed, including healing of the leak, morbidity and mortality.

RESULTS

Stents were inserted successfully in all 22 patients without procedure-related complications. Ten patients also required computed tomography-guided drainage because surgical drains had been removed. Non-ventilated patients received oral nutrition a mean of 4 days after stent placement. Combined treatment with stenting and drainage resulted in resolution of the leak in 21 of 22 patients. The mean healing time (time to stent removal) was 23 days. Stent migration occurred in five of 22 patients, but endoscopic reintervention with placement of a new stent was successful in all patients. Repeat thoracotomy with intraoperative stent placement was necessary in one patient with an oesophagocolonic anastomosis. One patient died in hospital.

CONCLUSION

In combination with effective drainage, self-expanding plastic stents are an option for the treatment of oesophageal anastomotic leaks, and may reduce leak-related morbidity and mortality.

Neoadjuvant chemotherapy versus surgery alone for locally advanced adenocarcinoma of the stomach and cardia: Randomized EORTC phase III trial #40954

4510

Background: Combined pre- and postoperative chemotherapy improves overall survival in operable gastric cancer, although postoperative treatment is not feasible in half of the patients. We conducted a randomized phase III trial with thorough attention to preoperative staging and to the extent of surgical resection to assess the value of neoadjuvant chemotherapy (CTx). Methods: Patients with locally advanced adenocarcinoma of the stomach and cardia were randomized between primary surgery or two 48-day cycles of weekly folinic acid 500 mg/m2/2h, 5-FU 2,000 mg/m2/24h plus biweekly cisplatin 50 mg/m2/1h followed by surgery. The study was designed to detect an improvement in median survival from 17 months with surgery to 24 months with CTx plus surgery (HR=0.708, power of 80%, type I error of 4% to allow for an interim analysis). It was planned to randomize 360 patients in order to observe the 262 deaths required for the final analysis. Results: From 7/99 to 2/04, 144 patients were randomized (72:72) with comparable baseline characteristics. Median follow-up is 4.4 years. Based on 67 deaths, overall survival between the two arms did not differ (HR=0.84; 95% CI: 0.52 to 1.35; p=0.466). Median survival exceeded 36 months in both arms. Due to low accrual, this trial was stopped early. The unexpected long median survival in the surgery arm would have made the primary objective difficult to reach anyway. Based on 77 events, difference in time to progression was borderline significant (HR=0.66; 95% CI, 0.42–1.03; p=0.065). Response rate to CTx was 35.2% (95% CI: 23.7%-45.7%). The R0-resection rate was 81.9 % after CTx as compared to 66.7% with surgery alone (P=0.036). There were no major differences in intra- or postoperative complications. Conclusions: This prematurely closed trial showed a significantly increased rate of R0 resections after CTx although it could not demonstrate a survival benefit. The outcome after a radical surgical procedure alone with extended lymphadenectomy was better than expected.

No significant financial relationships to disclose.

Lymphatic mapping and sentinel lymph node biopsy in epidermoid carcinoma of the anal canal

AIM

Although 15-25% of patients with anal cancer present with superficial inguinal lymph node metastases but the routine application of groin irradiation is controversial because of serious side effects. Inguinal sentinel lymph node biopsy (SLNB) can be used to select patients appropriately for inguinal radiation. The study evaluates the efficiency and clinical impact of SLNB.

METHODS

Forty patients with anal cancer underwent 1 ml Tc(99m)-Nanocolloid injection in four sites around the tumour. Patients with inguinal radio colloid enrichment were selected for sentinel lymph node biopsy (SLNB). Lymph node status was examined by haematoxylin and eosin (H&E) as well as immunohistochemistry-staining. All SLN-positive patients were scheduled for inguinal radiation; SLN-negative patients with T1 and early T2 tumours were not scheduled for inguinal radiation.

RESULTS

SLN were detected in 36/40 patients. Three common patterns of lymphatic drainage were observed: mesenterial, iliacal and inguinal. Twenty patients with inguinal SLN underwent SLN-biopsy. 6/20 patients were SLN-positive. In 10/20 patients SLNB altered the therapy plan--four patients with T1-tumours and positive SLN had additional groin irradiation, whereas 6 patients with small T2-tumors and tumour-free inguinal SLN did not undergo inguinal irradiation.

CONCLUSIONS

Inguinal sentinel node biopsy in anal cancer is efficient and could assist in the decision for inguinal radiation. The validity and safety of the proposed therapeutic algorithm has to be proven by a larger, prospective study.

Markers of tumour angiogenesis and tumour cells in bone marrow in gastric cancer patients

AIMS

Vascular endothelial growth factors VEGF-A, VEGF-C and VEGF-D are considered to be potentially angiogenetic and lymphangiogenetic. "Minimal residual disease" is responsible for cancer progression and recurrence. In this study, we investigated the relation between expressions of VEGF-A, VEGF-C and VEGF-D in gastric cancer tissue and the presence of tumour cells in bone marrow.

METHODS

A total of 50 resected primary gastric adenocarcinomas, 44 non-cancerous gastric mucosa and 36 lymph node metastases were analyzed by immunohistochemistry for VEGF-A, VEGF-C and VEGF-D. The specimens used were drawn from a previous study cohort, where the presence of ITC in bone marrow was confirmed with immunohistochemical assay with cytokeratin (CK)-18.

RESULTS

The levels of expression of VEGF-A, VEGF-C and VEGF-D were highest in tumour (p < 0.001), and the level in lymph node metastases was significantly higher (p < 0.01) than in mucosa. The expression of VEGF-A was correlated significantly with venous tumour invasion (p < 0.05) and the presence of tumour cells in bone marrow (p < 0.05). Tumours expressing high levels of VEGF-D showed significantly advanced stages of tumour infiltration (p < 0.05) and lymph node metastasis (p < 0.01).

CONCLUSIONS

VEGF-A is a significant marker for the presence of tumour cells in the bone marrow of gastric cancer patients. Our results confirm VEGF-D as a predictor for the lymphatic spread of tumour cells. Therefore, the route of metastatic spread of gastric cancer could be determined, at least in part, by the profile of VEGF family members expressed in the primary tumour of gastric cancer patients.

Sentinel lymph node biopsy for gastrointestinal cancers

Sentinel lymph node biopsy (SLNB) in gastrointestinal-(GI)-tract cancer is not yet of clinical relevance. Nevertheless, the results in the upper GI-tract promise to be helpful to individualize the indication for surgical therapy. SLNB in colon cancer still fails to show high validity to predict the nodal status, but may be helpful to clarify the prognostic role of micrometastases/isolated tumor cells. In anal cancer SLNB is able to guide the indication for groin irradiation.

Surgical strategies for gastric cancer with synchronous peritoneal carcinomatosis

BACKGROUND

Gastric cancer frequently spreads to the peritoneal cavity. Whether laparoscopy is useful in planning therapy remains controversial. The aim of this study was to investigate the value of laparoscopy and to develop a therapeutic algorithm.

METHODS

Six hundred and sixty consecutive patients with gastric cancer were included in this prospective observational study. The sensitivity of abdominal ultrasonography, computed tomography (CT) and laparoscopy for detecting peritoneal carcinomatosis was compared. The lesions were biopsied and classified as P1, P2 or P3 according to the recommendations of the Japanese Research Society for Gastric Cancer. Prognosis was determined according to the stage of peritoneal carcinomatosis and therapeutic procedure adopted.

RESULTS

One hundred and ten (16.7 per cent) of 660 patients presented with synchronous peritoneal carcinomatosis. The sensitivity for detecting peritoneal carcinomatosis was 85 per cent for laparoscopy compared with 19 per cent for ultrasonography and 28 per cent for CT. Patients with P3 disease did not benefit from additional surgery compared with chemotherapy alone. Those with P1 carcinomatosis had improved survival rates after complete resection followed by chemotherapy.

CONCLUSION

Laparoscopy improves the detection and classification of peritoneal carcinomatosis, and offers patients with gastric cancer a more individualized and effective therapy.

Impact of Patient- and Disease-Specific Factors on SLNB in Breast Cancer Patients. Are Current Guidelines Justified?

BACKGROUND

The evidence on which to base guidelines for sentinel lymph node biopsy (SLNB) in breast cancer is still limited. In order to facilitate the further implementation of renewed guidelines, we evaluated patient- and disease-specific factors for their impact on the results of SLNB.

MATERIALS AND METHODS

Prospective data acquisition from patients undergoing surgery for primary invasive breast cancer was performed. All patients underwent SLNB using the radiocolloid or the combined technique. The association of patient- and disease-specific factors to detection rate and false-negative rate was calculated using univariate and multivariate analyses (P < 0.05 considered as significant). Calculation of the false-negative rate was based on patients who underwent a backup axillary dissection.

RESULTS

Among 455 consecutively enrolled patients, a significant inverse association to the detection rate was found for extracapsular extension of non-SLN metastases, body mass index (BMI), number of involved lymph nodes, pT category, tumor size, and age. A significant association to the false-negative rate to identify macrometastases was found for pT category, tumor size, and grading. Other factors, such as prior surgery, multicentric tumor growth, or vascular invasion, showed no influence. A cut-point analysis revealed that a tumor size of 2 cm separated the collective of patients with the highest significance in regard to the false-negative rate (9% vs. 25%).

CONCLUSION

Our results indicate that SLNB can be safely used in elderly and obese patients with multicentric tumors and those having undergone prior surgery for benign breast disease. However, the method should be applied with caution in patients with tumors larger than 2 cm.

[Minimal residual tumor in gastrointestinal carcinoma. Relevance to prognosis and oncologic surgical consequences]

Isolated tumor cells as a consequence of minimal residual disease are often not detectable by routine diagnostic procedures. However, before or after surgery, isolated tumor cells in lymph nodes, the peritoneal cavity, blood, or bone marrow can frequently be identified by immunohistochemical or molecular methods. Failure to reveal the presence of such cells results in under-staging of tumor patients and may constitute the source of unexpected tumor recurrence after radical surgery. These facts emphasize the importance of isolated tumor cells at least as a surrogate marker. The frequency of appearance of isolated tumor cells in different organ systems also depends on the type of primary tumor. Developments in modern detection methods have led to increasing sensitivity but at the expense of specificity. Isolated tumor cells demonstrate remarkable heterogeneity with respect to proliferative potential and tumorigenicity. This characteristic is also reflected by a striking variability in the expression of various genes conditioning the aforementioned biological behavior. Unfortunately there is also remarkable heterogeneity in methods used for sampling and processing patient material as well as for the enrichment and detection of isolated tumor cells. Despite the ongoing controversies concerning detection methods and biological significance of isolated tumor cells, several clinical trials providing data supporting the prognostic relevance of minimal residual disease should also be considered for gastrointestinal carcinoma. In future this finding should be integrated in the planning of trials in surgical oncology, and "minimal residual disease" should receive stronger attention as a stratification criterion in such clinical studies.

[Optimization of staging in colon cancer using sentinel lymph node biopsy]

Routine determination of the nodal status in colon cancer is strongly dependent on the individual quality and technique of histopathological assessment and surgical lymph node dissection. We evaluated whether sentinel lymph node biopsy (SLNB) could contribute to an improvement in staging. At least one SLN (median n=2) was detected (detection rate 84%) in each of 38 of 45 patients with primary colon cancer. Ten of these 38 were found to have lymph node metastases by HE staining (26%), six of them in the SLN. Nine of the 28 patients that were initially nodal-negative by HE revealed one micrometastasis and eight cases of isolated tumor cells by immunohistochemical (IHC) staining (32% upstaging response). Including the IHC-positive cases, 19 of the 38 patients were nodal-positive (50%), 15 of them with tumor-infiltrated SLN (overall sensitivity of SLNB 79%). Using the dye method, SLNB is clinically practicable and leads in the majority of the patients to the detection of SLN. The selective, intensified histopathological assessment of SLN identifies small tumor cell deposits in a relevant percentage of patients with little and clinically practicable effort.

Prediction of gastric cancer lymph node status by sentinel lymph node biopsy and the Maruyama computer model

AIMS

The extent of lymph node dissection in gastric cancer remains controversial. The Maruyama computer model and the sentinel lymph node biopsy (SLNB) are compared for their value to predict the nodal status and lead to stage-adapted surgery.

METHODS

Thirty four patients with stage I-IV gastric cancer underwent both staging procedures. For SLNB, 15 patients underwent endoscopic, peri-tumoural injection of (99m)Tc-colloid, and 19 patients were injected of Patent blue V. All 'hot' or blue sentinel lymph nodes (SLNs) were separately excised and histopathologically assessed. If the SLN was negative after routine staining by H&E, it was processed completely and reanalysed after immunohistochemistry.

RESULTS

At least, one SLN was detected by means of SLNB in 33/34 of the patients. The sensitivity to identify a positive nodal status was 22/33 and the specificity/positive predictive value was 10/10 and 22/22. Additional micrometastases or isolated tumour cells in the SLN led to 'upstaging' of 5/15, initially classified as nodal negative by H&E-staining. Using the Maruyama computer model, a sensitivity of 22/23 for the correct prediction of the lymph node involvement was associated with a specificity of 2/10 and a positive predictive value of 22/30.

CONCLUSIONS

The clinical impact of the Maruyama computer model is limited due to low specificity and a low positive predictive value, rendering the method less useful as an indicator for individualised surgery.

Sentinel Lymph Node beim kolorektalen Karzinom

Lymph node status as an important prognostic factor in colon and rectal cancer is affected by the selection and number of lymph nodes examined and by the quality of histopathological assessment. The multitude of influences is accompanied by an elevated risk of quality alterations. Sentinel lymph node biopsy (SLNB) is currently under investigation for its value in improving determination of the nodal status. Worldwide, the data of 800 to 1000 patients from about 20 relatively small studies are available that focus rather on colon than rectal cancer patients. SLNB may be of clinical value for the collective of patients that are initially node-negative after H&E staining but reveal small micrometastases or isolated tumor cells in the SLN after intensified histopathological workup. If further studies confirm that these patients benefit from adjuvant therapy, the method may have an important effect on the therapy and prognosis of colon cancer patients as well. Another potential application could be the determination of the nodal status after endoscopic excision of early cancer to avoid bowel resection and lymphonodectomy.

Sentinel lymph node biopsy in rectal cancer--not yet ready for routine clinical use

BACKGROUND

The value of sentinel node biopsy in visceral cancers is uncertain. We evaluated the feasibility and utility of radiocolloid lymphatic mapping and selective lymph node sampling in patients with rectal cancer.

METHODS

Forty-eight patients with rectal cancer were investigated. Thirty-seven patients had already undergone preoperative radiochemotherapy for locally advanced tumors. Eleven patients underwent primary surgery. An endoscopic injection of 1 mL technetium 99m-sulfur-colloid into the peritumoral submucosa was performed 15 to 17 hours before surgery. Ex vivo identification of the nuclide-enriched "sentinel lymph nodes" (SLNs) was performed using a hand-held gamma-probe. The selected SLNs were then carefully and systematically examined using serial sections and immunohistochemistry.

RESULTS

One or more SLNs were found in 46 of the 48 patients. The SLN detection rate was 96%. Sixteen of the 48 patients had lymph node metastases (35%). In 7 of the 16 patients, the SLNs correctly represented the nodal status. In 9 of the 16 patients, the SLN was tumor-free whereas non-SLN harbored metastases. This result represents a sensitivity of only 44%, and a false-negative rate of 56%. Further analysis showed that the method correctly predicted the nodal status only in the small subgroup of 5 patients with early cancer without preoperative radiation. In 4 patients, juxtaregional lymph nodes were excised on the basis of intraoperative radiocolloid detection, leading to upward staging in 1 patient.

CONCLUSIONS

Sentinel lymph node biopsy using the radiocolloid technique with ex vivo lymph node identification shows a relatively high detection rate; however, the sensitivity in patients with locally advanced/irradiated rectal cancer is low. Nevertheless, the detection of juxtaregional metastases can improve staging in some patients. Further studies should focus on patients with early rectal cancers where the data were more promising.

Sentinel node biopsy in anal cancer - a promising strategy to individualize therapy

BACKGROUND

In order to individualize the therapy in patients with anal cancer, we evaluated the applicability of the sentinel lymph node (SLN) concept for the staging of inguinal lymph nodes in these patients.

PATIENTS AND METHOD

SLN mapping using the radiocolloid technique was performed in 12 patients with histopathologically proven anal cancer. Mean age of the 4 male and 8 female patients was 62 years (range: 37-83 years). All patients underwent injection of (99m)Tc-colloid (Nanocis) in 4 portions around the tumor followed by scintigraphy after 17 h and selective lymph node biopsy in case of nuclide enrichment. The nuclide-enriched lymph node was intraoperatively identified by a hand-held gamma-camera. Histopathological assessment of the harvested SLNs included serial sections and immunohistochemical staining.

RESULTS

Enrichment of radiocolloid in lymph nodes was seen in 10 of the 12 patients (detection rate: 83%). SLN biopsy was performed in 9 patients, one patient refused the SLN biopsy (SLNB). 4 patients revealed tumor-infiltrated sentinel lymph nodes including one patient with bilateral biopsy, who showed metastases unilaterally. The remaining 5 patients had no evidence of metastases in the excised SLNs.

CONCLUSION

It is feasible to evaluate the nodal status of the groin in patients with anal cancer using the radiocolloid technique. Preliminary results indicate a refined diagnostic work-up for anal cancer patients, potentially improving the results of clinical and sonographical examinations. Further application of the method may lead to an individualized treatment of patients with anal cancer.

New Concepts of Staging in Gastrointestinal Tumors as a Basis of Diagnosis and Multimodal Therapy

The therapy of gastrointestinal tumors is becoming more and more sophisticated and complex. This is due to an improved understanding of the pathogenesis of tumors, a more detailed classification and increasing therapeutic options. The basis of optimized therapeutic concepts is the exact evaluation of tumor spread and exact staging. The following review describes some of the most recent staging concepts in gastrointestinal tumors. Multislice computed tomography (CT), positron emission tomography (PET) and new supraparamagnetic iron oxide contrast agents for magnetic resonance imaging enable an increasing quality of the visualization of tumors and metastases. 3D imaging will be used for planning of surgical interventions in the future. Optical coherence tomography may contribute to an improved tumor staging and, thus, to the safety of limited interventions in early oesophageal- and gastric cancer patients. Laparoscopy and laparoscopic ultrasound become increasingly important for the identification of small metastases in the peritoneum, in lymph nodes and in the liver. The sentinel lymph node concept will contribute to an improved staging and individualized therapy as well.

Differenzierung von Leberläsionen mit SPIO-gestützten T1-w und T2-w MRT-Aufnahmen: Eine ROC-Analyse

PURPOSE

The superparamagnetic iron oxide (SPIO) Resovist is a contrast media with shortening of both T(1) and T(2) relaxation time. This study evaluates the impact of SPIO-enhanced T(1)- and T(2)-weighted images for the differentiation of liver lesions.

MATERIALS AND METHODS

SPIO-enhanced MRI examinations (1.5 T, Symphony Quantum) of 61 patients were analyzed. Thirty-seven patients had malignant liver lesions (metastases n = 32, HCC n = 5) proven by biopsy or laparotomy, 11 patients had benign liver lesions (FNH n = 2, hemangiomas n = 4, benign cysts n = 5, normal liver on laparoscopy n = 13). After unenhanced T(1)- and T (2)-weighted imaging, a bolus injection of 1.4 ml SPIO (Resovist) was given, followed by T(1)-weighted imaging at 20 s, 60 s, and 5 min and T(2)-weighted imaging at 10 min post injection. A score from 1 (benign) to 5 (malignant) was used by three blinded radiologist for the ROC analysis of the unenhanced T(1)-/T(2)-weighted images (set 1) and of the combinations of unenhanced T(1)/T(2)-weighted and SPIO T(1)-weighted images (set 2), unenhanced T(1)/T(2) and SPIO T(2)-w images (set 3) and all images (set 4).

RESULTS

The accuracy of plain MRI (set 1: 56 %) was increased by SPIO-enhanced T(1)-weighted images (set 2: 81 %) and SPIO-enhanced T(2)-weighted images (set 3: 90 %). Best results were obtained using unenhanced T(1)-weighted, unenhanced T(2)-weighted and both SPIO T(1)-weighted and T(2)-weighted images (set 4: 93%). The accuracy of predicting histopathologic diagnosis was 91%.

CONCLUSION

For the differentiation of liver lesions, SPIO-enhanced T(2)-weighted images had a greater impact on the accuracy of MRI than T (1)-weighted images, but SPIO-enhanced T(1)-weighted images provided additional information in some patients and should not be deleted.

[Reducing trauma with minimally invasive surgery. Evidence and new strategies]

Minimally invasive surgery has become a viable alternative to conventional surgery. The technical advantages of minimally invasive surgery can be translated into clinical benefits for the patients, i.e., less postoperative pain and impairment of lung function, better cosmetic results, shorter hospitalization, and earlier convalescence. Laparoscopic operations have replaced a significant proportion of open surgical procedures and are now routinely used. While the role of laparoscopic surgery has been generally accepted for the management of benign disorders, there is ongoing debate regarding the adequacy of this technique in surgical oncology. There is evidence that minimally invasive surgery can reduce perioperative morbidity in cancer patients. However, definite validation of these procedures for tumor surgery is not yet available due to the lack of prospective randomized trials providing reliable long-term data on disease-free survival and overall survival. It seems likely that minimally invasive procedures will play an important role for the treatment of preneoplastic lesions and tumors of limited size.

[Lymphatic mapping and sentinel lymph node biopsy in gastric cancer]

INTRODUCTION

Lymphatic mapping and the sentinel lymph node (SLN) concept has been validated in malignant melanoma and breast cancer.However, the application for other solid tumors is still controversial. One of the most promising approaches is selective lymph node staging in gastric cancer.The presented pilot study evaluated the feasibility of the radiocolloid technique in gastric cancer patients and its value in predicting a positive nodal status.

PATIENTS AND METHODS

Fifteen patients with gastric cancer (u T(1-3)) underwent endoscopic submucosal injection of 0.4 ml 60 MBq (99m)Tc-Nanocis around the tumor 17 (+/-3) h prior to surgery. After laparotomy the activity of all 16 (JGCA) lymph node stations was measured by a handheld probe. All patients underwent standard gastrectomy with systematic D2 lymphadenectomy. After resection the site was scanned for residual activity. All sentinel lymph nodes (SLN's) were removed ex vivo from the resected specimen and processed for intensified histopathologic assessment including serial sections and immunohistochemistry.

RESULTS

In 14 of 15 patients at least one or more SLN's were obtained (93%), the median number of SLN's was 3 (1-5). Of the 14 patients, 9 revealed lymph node metastases. In eight of the nine patients the sentinel node(s) correctly predicted metastatic lymph node invasion. In five cases the lymph node station with positive sentinel node(s) was the only positive node station resulting in a sensitivity of 8/9 (89%). In one case immunohistochemical staining revealed micrometastases leading to an upstaging in 1/6 of the initially nodal-negative patients.

CONCLUSION

Lymphatic mapping and sentinel node biopsy using the radiocolloid technique is feasible in gastric cancer. Limited results indicate a correct prediction of the nodal status and the potential of upstaging.Further studies seem to be justified to evaluate the clinical impact of the method.

Sentinel lymphonodectomy in gastrointestinal cancer--where are we now?

Up to now, no reliable methods for the pre- or intraoperative prediction of the nodal status are available in gastrointestinal cancer patients. Therefore, after the successful application of the sentinel lymph node concept in melanoma and breast cancer, ongoing research on this field is extended to gastrointestinal tumor entities. According to recent experiences, the most promising tumor entities are colon, gastric and anal cancer. First results with these patients indicate that the method could be a reliable predictor of the nodal status and, thus, may have important future implications for adjuvant therapy and the extent of surgery. The dye method for colon cancer and the combined method (dye and radiocolloid) for gastric cancer seem to be appropriate approaches, even when the general experience is still low. In rectal cancer, however, current experience failed yet to yield satisfying results. Up to now, anal cancer has not been a focus of publication, even when the concept seems to be very attractive for the evaluation of the inguinal lymph node status.

[Laser-induced thermotherapy (LITT) for malignant liver tumours: the role of sonography in catheter placement and observation of the therapeutic procedure]

AIM

Evaluation of sonography in the placement of catheters for laser-induced thermotherapy (LITT) as well as for the observation of the therapeutic procedure in cases of malignant liver tumours.

METHODS

Following the placement of 1-4 LITT applicators, 18 patients with malignant liver tumours (recurrence of hepatocellular carcinoma n = 5, metachronous liver metastases n = 13) were examined by ultrasound to determine the position of the applicators as well as the sonographic visualisation of the respective lesion. The laser treatment procedure was also observed sonographically. As standard reference method for the documentation of thermally induced necroses we used magnetic resonance tomography 24-48 hours after the procedure.

RESULTS

The tip of the applicator could be localised in all cases, and the position of the applicator relative to the lesion could be directly visualised in 78% of cases. The hyperechogenic thermal effect during LITT had a median size of 4.5 cm, thus proving to be significantly larger than the actual necrosis induced (p < 0.01). The sonographic observation of the procedure identified 8/10 primarily incomplete ablations which were then treated again immediately after correction of the position of the applicators.

CONCLUSION

Continuous sonographic observation of the procedure of LITT can yield important additional information.

Regression of high-grade gastric B-cell lymphoma after eradication of Helicobacter pylori

Regression of high-grade gastric B-cell lymphoma after eradication of Helicobacter pylori with antibiotic therapy has recently been shown in a very small number of patients. We describe here a patient with a 5-cm polypoid gastric lymphoma, who received a 7-day course of triple therapy when the histopathology was unknown. A second endoscopic examination 4 weeks later showed partial tumor regression without biopsy evidence of malignancy. Endoscopic mucosectomy was performed 8 weeks after the initial diagnosis. Again, in the histological analysis of the specimen, no evidence of B-cell lymphoma could be found. To confirm that the original biopsies were from the same patient, DNA analyses were carried out which gave identical results. This case suggests that a subgroup of primary gastric B-cell lymphomas responds to eradication of H. pylori with antibiotic therapy.

Overexpression of sialyltransferase CMP-sialic acid:Galbeta1,3GalNAc-R alpha6-Sialyltransferase is related to poor patient survival in human colorectal carcinomas

Thomsen-Friedenreich (TF)-related blood group antigens, such as TF, Tn, and their sialylated variants, belong to a family of tumor-associated carbohydrates. The aim of the present study was to examine tumor-associated alterations of glycosyltransferases involved in the biosynthesis of the TF glycotope in colorectal carcinomas. To this end, glycosyltransferase expression was examined in 40 cases of colorectal carcinoma specimens classified according to the WHO/Union International Contre Cancer guidelines and in "normal" mucosa of the same patients. Occurrence of TF glycotope was examined by immunohistochemistry with the monoclonal antibody A78-G/A7. Expression of sialyltransferases CMP-sialic acid:Galbeta1,3GalNAc-R alpha3-sialyltransferase I and II (ST3Gal-I and ST3Gal-II) and CMP-sialic acid:Galbeta1,3GalNAc-R alpha6-sialyltransferase (ST6GalNAc-II) and of core 2 beta1,6-N-acetylglucosaminyltransferase was determined by reverse transcription-PCR in the same cryostat sections used for immunohistochemistry. Additionally, alpha2,3-sialyltransferase enzyme activity was studied in each of these tissues. The TF glycotope was detected in 7% of the normal mucosa, but in 57% of the carcinoma samples. Expression of alpha2,3-sialyltransferases ST3Gal-I, ST3Gal-II, and enzyme activity of alpha2,3-sialyltransferase was significantly increased (P < 0.001) in carcinoma specimens compared with normal mucosa. ST3Gal-I mRNA expression was significantly increased (P = 0.05) in cases showing invasion of lymph vessels. Expression of ST6GalNAc-II was significantly increased (P = 0.04) in cases with metastases to lymph nodes along the vascular trunk. Moreover, ST6GalNAc-II expression provides an prognostic factor for patient survival (log rank, P = 0.02). In an attempt to study the functional relevance of the glycosyltransferases for TF biosynthesis, SW480 colorectal cells were transfected with each of the enzymes, and cell surface expression of the TF glycotope was examined by flow cytometry. The presence of TF was not altered by transfection of the cells with either sialyltransferase ST3Gal-I or ST3Gal-II. However, successful transfection with core 2 beta1,6-N-acetylglucosaminyltransferase led to reduced expression of TF. In contrast, increased cell surface expression of TF was found after ST6GalNAc-II transfection. Thus, expression of TF on the cell surface of SW480 colorectal carcinoma cells depends on the ratio of core 2 beta1,6-N-acetylglucosaminyltransferase and ST6GalNAc-II. Earlier immunohistological studies demonstrated that TF is a prognostic factor for patient survival. Our results suggest that sialyltransferase ST6GalNAc-II is of crucial relevance for the prognostic significance of TF.

Wolf in sheep's clothing: spilled gallstones can cause severe complications after endoscopic surgery

Bile concrements may remain intraperitoneally after laparoscopic cholecystectomy. Previously, this was considered harmless, a view supported by some experimental studies. Recently, however, spilled gallstones have been identified as a source of rare but potentially serious complications. We report a case of a retrohepatic abscess and dorsal fistulation after laparoscopic cholecystectomy. Healing was achieved only by repeated surgery, including abscess drainage, stone removals, and fistula excision. Since 1990, 73 cases with gallstone-related complications after laparoscopic cholecystectomy have been reported in the literature. Among these complications, intra-abdominal abscesses and transabdominal fistulas were predominant. The interval between the cholecystectomy and the appearance of complications ranged from 4 days to 29 months, with a peak incidence at 4 months. Spillage of small bile concrements or fragments is, with the exception of multiple irremovable stones, not commonly an indication for conversion to an open procedure. However, the patient needs to be warned about the risk of gallstone loss and its associated complications at the time when informed consent is obtained. Furthermore, if gallstone loss has occurred, the patient should be informed, and the occurrence should be documented.

[The importance of delay in patients with tumors exemplified by pretreatment of locally advanced rectal carcinoma]

BACKGROUND

With the intention to achieve tumor reduction and thereby increase R0-resection rate, preoperative radiochemotherapy is increasingly applied in locally advanced rectum cancer. Along with the advantages of prior therapy, a delay of surgical treatment occurs which might despite continuing therapy give way to local tumor progression or metastatic disease.

PATIENTS AND METHODS

Since 1993 we have treated locally advanced rectum carcinomas by preoperative radiotherapy according to a preoperative study protocol. We analyzed the incidence of local tumor progression or metastases during the 12 weeks of preoperative treatment. Hundred and fifteen patients with histologically proven primary rectum carcinoma without evidence of regional or distant metastases and endosonographically determined infiltration depth of stage T3 or more underwent preoperative radiochemotherapy between 3/1993 and 10/1999. Hundred and eight patients (88 times uT3 and (20 times uT4) have been operated and examined afterwards with respect to response to prior treatment. Before and after preoperative therapy, endorectal ultrasound was performed to evaluate local response. Distant metastatic manifestations were excluded by radiography and ultrasound scanning.

RESULTS

A reduction of the infiltration depth was observed in 55 patients (51%). Tumor size remained unchanged in 50 patients (46%). Only 3 patients (3%) showed tumor growth in histological assessment. Fifty-seven patients (53%) showed no change in lymph node status after preoperative therapy, whereas lymph node metastases were detected in 11 patients (10%) who were judged uN0 preoperatively. We discovered metastases in 6 patients (6%) after preoperative therapy.

CONCLUSION

During preoperative therapy, tumor progress is not entirely evitable. Considering the lack of precision in pretherapeutic staging diagnostics, we conclude that delays due to therapeutic regimen are responsible for prognostic disadvantage in only a small number of patients.

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.

[Significance of alpha 2,6-specific sialyltransferase ST6N and alpha 2,3-specific sialyltransferase ST3N in stomach carcinoma]

The objective of this prospective study was to investigate the role of sialytransferase activities in patients with gastric cancer. In patients with gastric cancer we observed a significant correlation between sialyltransferase ST6N levels and survival after a median follow up of one year. High ST6N levels in the tumor and the surrounding normal mucosa were associated with poor prognosis. The results of this pilot study encourage further evaluation of sialyltransferase in patients with gastric cancer.

Three-dimensional endoscopic ultrasound of the esophagus. Preliminary experience

BACKGROUND

The aim of this study was to develop a technique for three-dimensional endoscopic ultrasound of the esophagus based on standard ultrasonic images.

METHODS

Endoscopic ultrasound was performed in five esophageal cancer patients using a high-resolution miniprobe (360 degrees, 12.5 MHz). For acquisition of three-dimensional data sets, the miniprobe was attached to a stepping motor that enabled ECG-triggered withdrawal of the transducer. Three-dimensional images were reconstructed from serial transverse sections on a PC-based 3D work station.

RESULTS

Twelve volume scans were obtained in five patients with esophageal cancer. The system enabled the acquisition of accurate three-dimensional ultrasound data within 30-50 s. Computed image processing allowed us to display the data in transverse, longitudinal, and oblique sections, or as a 3D reconstruction. Three-dimensional imaging provided accurate visualization of the tumor and surrounding structures in all cases. The tumor stage was determined correctly in four of five patients. Longitudinal scan planes and 3D views improved the assessment of longitudinal tumor infiltration and the spatial relation of the tumor to relevant mediastinal structures.

CONCLUSION

This study shows that three-dimensional endoscopic ultrasound of the esophagus is technically feasible. The technique allows the assessment of local tumor spread in previously unattainable scan planes and 3D views. This promising preliminary experience should encourage further exploration of this method.

[Value of endosonography in tumors of the upper GI tract in comparison with different scanners (Radial 360 degrees and Sector Scanner 120 degrees]

This comparative study was performed to determine the value of two endosonography devices, i.e, the radial and the longitudinal transducer, for staging upper GI tract cancer. The accuracy of both methods was comparable in esophageal cancer, whereas radial scanning was superior in gastric cancer. Generally radial scanning provided better spatial orientation and was easier to assess. An advantage of the longitudinal curved array scanner is the feasibility of EUS-guided biopsy.