[Surgery for pancreatic cancer]

Neoadjuvant radiotherapeutic strategies in pancreatic cancer

This review summarizes the current status of neoadjuvant radiation approaches in the treatment of pancreatic cancer, including a description of modern radiation techniques, and an overview on the literature regarding neoadjuvant radio- or radiochemotherapeutic strategies both for resectable and irresectable pancreatic cancer. Neoadjuvant chemoradiation for locally-advanced, primarily non- or borderline resectable pancreas cancer results in secondary resectability in a substantial proportion of patients with consecutively markedly improved overall prognosis and should be considered as possible alternative in pretreatment multidisciplinary evaluations. In resectable pancreatic cancer, outstanding results in terms of response, local control and overall survival have been observed with neoadjuvant radio- or radiochemotherapy in several phase I/II trials, which justify further evaluation of this strategy. Further investigation of neoadjuvant chemoradiation strategies should be performed preferentially in randomized trials in order to improve comparability of the current results with other treatment modalities. This should include the evaluation of optimal sequencing with newer and more potent systemic induction therapy approaches. Advances in patient selection based on new molecular markers might be of crucial interest in this context. Finally modern external beam radiation techniques (intensity-modulated radiation therapy, image-guided radiation therapy and stereotactic body radiation therapy), new radiation qualities (protons, heavy ions) or combinations with alternative boosting techniques widen the therapeutic window and contribute to the reduction of toxicity.

[Delayed complications after pancreatic surgery: Pancreatic insufficiency, malabsorption syndrome, pancreoprivic diabetes mellitus and pseudocysts]

BACKGROUND

Benign and malignant pathologies of the pancreas can result in a relevant chronic disease burden. This is aggravated by morbidities resulting from surgical resections as well as from progression of the underlying condition.

OBJECTIVE

The aim was to summarize the current evidence regarding epidemiology, pathophysiology, diagnosis and treatment of endocrine and exocrine pancreatic insufficiency, as well as of pancreatic pseudocysts.

MATERIAL AND METHODS

A selective literature search was performed and a summary of the currently available data on the surgical sequelae after pancreatic resection is given.

RESULTS

Reduction of healthy pancreatic parenchyma down to 10-15 % leads to exocrine insufficiency with malabsorption and gastrointestinal complaints. Orally substituted pancreatic enzymes are the therapy of choice. Loss of pancreatic islets and/or islet function leads to endocrine insufficiency and pancreoprivic diabetes mellitus. Inflammatory, traumatic and iatrogenic injuries of the pancreas can lead to pancreatic pseudocysts, which require endoscopic, interventional or surgical drainage if symptomatic. Finally, pancreatic surgery harbors the long-term risk of gastrointestinal anastomotic ulcers, bile duct stenosis, portal vein thrombosis and chronic pain syndrome.

CONCLUSION

As the evidence is limited, an interdisciplinary and individually tailored approach for delayed pancreatic morbidity is recommended.

A clinical phase I/II trial to investigate preoperative dose-escalated intensity-modulated radiation therapy (IMRT) and intraoperative radiation therapy (IORT) in patients with retroperitoneal soft tissue sarcoma

Background

The current standard treatment, at least in Europe, for patients with primarily resectable tumors, consists of surgery followed by adjuvant chemotherapy. But even in this prognostic favourable group, long term survival is disappointing because of high local and distant failure rates. Postoperative chemoradiation has shown improved local control and overalls survival compared to surgery alone but the value of additional radiation has been questioned in case of adjuvant chemotherapy. However, there remains a strong rationale for the addition of radiation therapy considering the high rates of microscopically incomplete resections after surgery. As postoperative administration of radiation therapy has some general disadvantages, neoadjuvant and intraoperative approaches theoretically offer benefits in terms of dose escalation, reduction of toxicity and patients comfort especially if hypofractionated regimens with highly conformal techniques like intensity-modulated radiation therapy are considered.

Methods/Design

The NEOPANC trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant short course intensity-modulated radiation therapy (5 × 5 Gy) in combination with surgery and intraoperative radiation therapy (15 Gy), followed by adjuvant chemotherapy according to the german treatment guidelines, in patients with primarily resectable pancreatic cancer. The aim of accrual is 46 patients.

Discussion

The primary objectives of the NEOPANC trial are to evaluate the general feasibility of this approach and the local recurrence rate after one year. Secondary endpoints are progression-free survival, overall survival, acute and late toxicity, postoperative morbidity and mortality and quality of life.

Trial registration

NCT01372735.

A clinical phase I/II trial to investigate preoperative dose-escalated intensity-modulated radiation therapy (IMRT) and intraoperative radiation therapy (IORT) in patients with retroperitoneal soft tissue sarcoma

BACKGROUND

Local control rates in patients with retroperitoneal soft tissue sarcoma (RSTS) remain disappointing even after gross total resection, mainly because wide margins are not achievable in the majority of patients. In contrast to extremity sarcoma, postoperative radiation therapy (RT) has shown limited efficacy due to its limitations in achievable dose and coverage. Although Intraoperative Radiation Therapy (IORT) has been introduced in some centers to overcome the dose limitations and resulted in increased outcome, local failure rates are still high even if considerable treatment related toxicity is accepted. As postoperative administration of RT has some general disadvantages, neoadjuvant approaches could offer benefits in terms of dose escalation, target coverage and reduction of toxicity, especially if highly conformal techniques like intensity-modulated radiation therapy (IMRT) are considered.

METHODS/DESIGN

The trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant dose-escalated IMRT (50-56 Gy) followed by surgery and IORT (10-12 Gy) in patients with at least marginally resectable RSTS. The primary objective is the local control rate after five years. Secondary endpoints are progression-free and overall survival, acute and late toxicity, surgical resectability and patterns of failure. The aim of accrual is 37 patients in the per-protocol population.

DISCUSSION

The present study evaluates combined neoadjuvant dose-escalated IMRT followed by surgery and IORT concerning its value for improved local control without markedly increased toxicity.

TRIAL REGISTRATION

NCT01566123.

Association between miR-224 expression and cell proliferation and apoptosis in pancreatic cancer

AIM: To investigate the expression of miR-224 in pancreatic carcinoma and to evaluate the role of miR-224 in pancreatic cancer cell proliferation and apoptosis.

METHODS: The expression of miR-224 in 40 pancreatic carcinoma tissue specimens and matched tumor-adjacent nontumorous tissue specimens was detected by real-time fluorescence PCR. After using the antisense technology to decrease the expression of miR-224 in pancreatic cancer cells (Aspc-1 and Bxpc-3), MTT assay and flow cytometry were performed to investigate the impact of miR-224 down-regulation on cell proliferation, cell cycle progression and apoptosis.

RESULTS: MiR-224 was found to be overexpressed in 43% of pancreatic carcinoma cases (P < 0.05). After antisense microRNA-mediated knockdown of miR-224, the proliferation of Aspc-1 and Bxpc-3 cells was significantly inhibited. Aspc-1 and Bxpc-3 cells were mainly arrested in G₀/G₁ phase, and the percentage of cells in S and G2/M phases decreased. In addition, miR-224 knockdown in Aspc-1 and Bxpc-3 cells resulted in an increase in early apoptosis.

CONCLUSION: MiR-224 is overexpressed in human pancreatic carcinoma. Inhibition of miR-224 expression can not only effectively suppress growth but also induce cell apoptosis of Aspc-1 and Bxpc-3 cells. MiR-224 may serve as a new molecular target for the treatment of pancreatic carcinoma.

[Diagnosis and definition of anastomotic leakage from the surgeon's perspective]

The leak rates of different gastrointestinal anastomoses vary considerably but despite this there are common and general concepts for diagnosis and management. Early diagnosis and timely consistent therapy must guide management to prevent harm to the patients. Diagnosis of anastomotic leaks is coupled to clinical signs of the patients and should be initiated promptly. Dependent on the localization of the leak, computed tomography with administration of oral or rectal contrast dye and endoscopy are of high diagnostic value. Both procedures guarantee the option of drainage or stenting through interventional drains or stent placement. Only the implementation of uniform definitions of anastomotic leaks enables surgeons to compare and to improve surgical treatment. Over recent years consensus definitions of postoperative complications including bile leak, pancreatic fistula and colorectal leak have been formulated. These definitions are based on a 3-fold increase of bilirubin (bile leak) or amylase levels (pancreatic fistula) in abdominal drainage fluid compared to serum levels or on an intestinal wall defect with communication of the intraluminal and extraluminal compartments (colorectal anastomosis). The definitions each describe three severity grades A-C. A change of clinical management is required in grade B whereas grade C usually requires a re-operation. Comparable consensus definitions for anastomotic leaks following esophagogastrostomy or esophagojejunostomy or following small bowel anastomosis have not been established. The authors strongly recommend implementation of the presented consensus definitions into clinical and academic daily practice.

Neoadjuvant therapy in patients with pancreatic cancer: a disappointing therapeutic approach?

Pancreatic cancer is a devastating disease. It is the fourth leading cause of cancer-related death in Germany. The incidence in 2003/2004 was 16 cases per 100.000 inhabitants. Of all carcinomas, pancreatic cancer has the highest mortality rate, with one- and five-year survival rates of 25% and less than 5%, respectively, regardless of the stage at diagnosis. These low survival rates demonstrate the poor prognosis of this carcinoma. Previous therapeutic approaches including surgical resection combined with adjuvant therapy or palliative chemoradiation have not achieved satisfactory results with respect to overall survival. Therefore, it is necessary to evaluate new therapeutic approaches. Neoadjuvant therapy is an interesting therapeutic option for patients with pancreatic cancer. For selected patients with borderline or unresectable disease, neoadjuvant therapy offers the potential for tumor downstaging, increasing the probability of a margin-negative resection and decreasing the occurrence of lymph node metastasis. Currently, there is no universally accepted approach for treating patients with pancreatic cancer in the neoadjuvant setting. In this review, the most common neoadjuvant strategies will be described, compared and discussed.

LigaSure versus conventional dissection technique in pancreatoduodenectomy: a pilot study

BACKGROUND

Pancreatic surgery requires extensive preparation and tissue dissection. Therefore, LigaSure (Valleylab, Boulder, CO) provides an alternative to conventional dissection techniques. The aim of the present study was to describe the feasibility, safety, and cost efficiency of LigaSure in pancreatoduodenectomy.

METHODS

Seven patients underwent surgery with the Ligasure and 7 patients underwent surgery with conventional dissection techniques. The patients were investigated for surgical time, intraoperative blood loss, complications, mortality, duration of hospital stay, and surgery-related costs.

RESULTS

Surgical time was 207 minutes in the LigaSure group and 255 minutes in the conventional group (P = .020). Intraoperative blood loss was 271 and 771 mL, respectively (P = .010). Other perioperative outcomes were comparable. The respective surgery-related costs averaged €4,125 and €4,931 (P = .023).

CONCLUSIONS

The use of LigaSure in pancreatoduodenectomy seems to be feasible and safe. In addition, it might lead to a reduction in the surgery-related costs.

Resectable pancreatic cancer: who really benefits from resection?

BACKGROUND

The 1-year disease-related mortality after resection for pancreatic cancer is approximately 30%. This study examined potential preoperative parameters that would help avoid unnecessary surgery.

METHODS

Among the patients resected at our institution from 1997 to 2006, a total of 228 underwent pancreatic resection for ductal adenocarcinoma. By means of a survival cutoff of 12 months, two groups were created: early death (ED) and long survivors. A logistic regression analysis was performed to identify perioperative predictors of ED.

RESULTS

Among 228 resected patients, postoperative mortality occurred in four cases (1.8%) that were excluded from the study. In the remaining 224 patients, 43 (19.2%) died of disease within 12 months from surgery (ED), and the remaining 181 (80.8%) had a longer survival. Multivariate analysis selected duration of preoperative symptoms > 40 days, CA 19-9 > 200 U/mL, pathological grading G3-G4, and R2 resection as independent predictors of ED.

CONCLUSIONS

Duration of symptoms, CA 19-9 serum level, and pathological grading possibly retrieved by endoscopic ultrasound-guided biopsy can be preoperatively used to identify patients with disease that is not suitable for up-front surgery, even if deemed resectable by high-quality imaging.

Postoperative care following pancreatic surgery: surveillance and treatment

BACKGROUND

After pancreatic surgery, some patients have complications that require treatment.

METHOD

Review article based on a selective literature search and the German S3 guideline on pancreatic carcinoma.

RESULTS

Detailed knowledge of the surgical procedure and its potential early and late complications is a prerequisite for the recognition and treatment of problems occurring after pancreatic surgery. These may be due either to the operation itself or to the progression of the underlying pancreatic disease. Both diabetes mellitus and exocrine insufficiency are common long-term sequelae. If persistent pain should arise, its cause must be identified and treated. To prevent malnutrition and vitamin deficiency after pancreatic resection, patients should be given a diet with an increased fat content and with supplemental enzymes.

CONCLUSION

Appropriate methods are available for the accurate diagnosis and, in most cases, successful treatment of complications arising after pancreatic surgery.