Multidetector CT evaluation of the course of nonresectable pancreatic carcinomas with neoadjuvant therapy

[Resectability of pancreatic cancer: New criteria]

BACKGROUND

Pancreatic cancer is notoriously one of the most aggressive cancers and still has a poor prognosis. Surgical resection is the only chance for a curative therapy approach, with which at least a 5‑year survival can be achieved for 25% of patients. Recent advances in surgical techniques have led to a change in the criteria for resectability.

OBJECTIVE

This review summarizes the currently available evidence on the criteria for resectability of pancreatic cancer and discusses the treatment options.

MATERIAL AND METHODS

The study was based on a selective literature search and a summary of the latest data on criteria for resectability is given.

RESULTS

Patients with pancreatic cancer must be differentiated into those with primarily resectable disease, borderline resectable disease, locally advanced (primarily unresectable) and metastatic disease. While infiltration into the major surrounding venous vessels (e.g. superior mesenteric vein, portal vein and confluence of splenic vein) used to be a criterion for unresectable disease, these tumors can nowadays be safely resected in specialized centers. Tumor infiltration into adjacent arteries (e.g. hepatic artery, superior mesenteric artery and celiac artery) remains a clinical problem and surgical resection is often technically possible but associated with an increased morbidity and mortality and therefore not generally recommended. Borderline resectable tumors represent a special group for which neoadjuvant treatment concepts are increasingly being implemented. Radiological therapy response evaluation is challenging after neoadjuvant therapy as it is not usually associated with a radiologically detectable reduction in tumor volume.

CONCLUSION

Pancreatic resections can nowadays be more radically performed due to advances in surgical techniques. This has led to a change in the criteria for resectability, especially concerning venous tumor infiltration.

Development and validation of automatic tools for interactive recurrence analysis in radiation therapy: optimization of treatment algorithms for locally advanced pancreatic cancer

BACKGROUND

In radiation oncology recurrence analysis is an important part in the evaluation process and clinical quality assurance of treatment concepts. With the example of 9 patients with locally advanced pancreatic cancer we developed and validated interactive analysis tools to support the evaluation workflow.

METHODS

After an automatic registration of the radiation planning CTs with the follow-up images, the recurrence volumes are segmented manually. Based on these volumes the DVH (dose volume histogram) statistic is calculated, followed by the determination of the dose applied to the region of recurrence and the distance between the boost and recurrence volume. We calculated the percentage of the recurrence volume within the 80%-isodose volume and compared it to the location of the recurrence within the boost volume, boost + 1 cm, boost + 1.5 cm and boost + 2 cm volumes.

RESULTS

Recurrence analysis of 9 patients demonstrated that all recurrences except one occurred within the defined GTV/boost volume; one recurrence developed beyond the field border/outfield. With the defined distance volumes in relation to the recurrences, we could show that 7 recurrent lesions were within the 2 cm radius of the primary tumor. Two large recurrences extended beyond the 2 cm, however, this might be due to very rapid growth and/or late detection of the tumor progression.

CONCLUSION

The main goal of using automatic analysis tools is to reduce time and effort conducting clinical analyses. We showed a first approach and use of a semi-automated workflow for recurrence analysis, which will be continuously optimized. In conclusion, despite the limitations of the automatic calculations we contributed to in-house optimization of subsequent study concepts based on an improved and validated target volume definition.

Advanced-stage pancreatic cancer: therapy options

Pancreatic ductal adenocarcinoma is one of the most aggressive cancers, and surgical resection is a requirement for a potential cure. However, the majority of patients are diagnosed with advanced-stage disease, either metastatic (50%) or locally advanced cancer (30%). Although palliative chemotherapy is the standard of care for patients with metastatic disease, management of locally advanced adenocarcinoma is controversial. Several treatment options, including extended surgical resections, neoadjuvant therapy with subsequent resections, as well as palliative radiotherapy and/or chemotherapy, should be considered. However, there is little evidence available to support treatment options for locally advanced disease. As valid predictive biomarkers for stratification of therapy are not available today, future trials need to define the role of the different treatment options. This Review summarizes the current evidence and discusses available treatment options for both locally advanced and metastatic pancreatic adenocarcinoma.

Part 1: CT characterisation of pancreatic neoplasms: a pictorial essay

The pancreas is a site of origin of a diverse range of benign and malignant tumours, and these are frequently detected, diagnosed and staged with computed tomography (CT). Knowledge of the typical appearance of these neoplasms as well as the features of locoregional invasion is fundamental for all general and abdominal radiologists. This pictorial essay aims to outline the characteristic CT appearances of the spectrum of pancreatic neoplasms, as well as important demographic and clinical information that aids diagnosis. The second article in this series addresses common mimics of pancreatic neoplasia.