Long-term survival after pancreatic cancer treatment

Pancreatic cancer: a symptomless killer

Pancreatic cancer is the fifth most common cause of cancer death in the UK. This disease often remains undiagnosed until it is at a late stage, resulting in the majority of tumours being unsuitable for surgical resection. When a diagnosis of pancreatic cancer is confirmed, early input from the multi-disciplinary team (MDT) is vital. Due to the poor prognosis, the screening and treatment of pancreatic cancer remains a considerable challenge for medicine in the 21st century.

Sonoporation-enhanced chemotherapy significantly reduces primary tumour burden in an orthotopic pancreatic cancer xenograft

PURPOSE

Adenocarcinoma of the pancreas remains one of the most lethal human cancers. The high mortality rates associated with this form of cancer are subsequent to late-stage clinical presentation and diagnosis, when surgery is rarely possible and of modest chemotherapeutic impact. Survival rates following diagnosis with advanced pancreatic cancer are very low; typical mortality rates of 50% are expected within 3 months of diagnosis. However, adjuvant chemotherapy improves the prognosis of patients even after palliative surgery, and successful newer neoadjuvant chemotherapeutical modalities have recently been reported. For patients whose tumours appear unresectable, chemotherapy remains the only option. During the past two decades, the nucleoside analogue gemcitabine has become the first-line chemotherapy for pancreatic adenocarcinoma. In this study, we aim to increase the delivery of gemcitabine to pancreatic tumours by exploring the effect of sonoporation for localised drug delivery of gemcitabine in an orthotopic xenograft mouse model of pancreatic cancer.

EXPERIMENTAL DESIGN

An orthotopic xenograft mouse model of luciferase expressing MIA PaCa-2 cells was developed, exhibiting disease development similar to human pancreatic adenocarcinoma. Subsequently, two groups of mice were treated with gemcitabine alone and gemcitabine combined with sonoporation; saline-treated mice were used as a control group. A custom-made focused ultrasound transducer using clinically safe acoustic conditions in combination with SonoVue® ultrasound contrast agent was used to induce sonoporation in the localised region of the primary tumour only. Whole-body disease development was measured using bioluminescence imaging, and primary tumour development was measured using 3D ultrasound.

RESULTS

Following just two treatments combining sonoporation and gemcitabine, primary tumour volumes were significantly lower than control groups. Additional therapy dramatically inhibited primary tumour growth throughout the course of the disease, with median survival increases of up to 10% demonstrated in comparison to the control groups.

CONCLUSION

Combined sonoporation and gemcitabine therapy significantly impedes primary tumour development in an orthotopic xenograft model of human pancreatic cancer, suggesting additional clinical benefits for patients treated with gemcitabine in combination with sonoporation.

Docetaxel- and 5-FU-concurrent radiotherapy in patients presenting unresectable locally advanced pancreatic cancer: a FNCLCC-ACCORD/0201 randomized phase II trial's pre-planned analysis and case report of a 5.5-year disease-free survival

Background

To explore possible improvement in the treatment of locally advanced pancreatic carcinoma (LAPC) we performed a randomized, non-comparative phase II study evaluating docetaxel - plus either daily continuous 5 FU or weekly cisplatin concurrent to radiotherapy. We report here the results of the docetaxel plus 5 FU regimen stopped according to the interim analysis. The docetaxel plus cisplatin arm was continued.

Methods

Forty (40) chemotherapy-naive patients with unresectable LAPC were randomly assigned (1:1) to either continuous fluorouracil (5-FU) 200 mg/m²/day (protracted IV) and docetaxel (DCT) 20 mg/m²/week or DCT 20 mg/m² and cisplatin (CDDP) 20 mg/m², plus concurrent radiotherapy for a period of 6 weeks. The radiation dose to the primary tumor was 54 Gy in 30 fractions. The trial's primary endpoint was the 6-month crude non-progression rate (NPR). Secondary endpoints were tolerance, objective response rate, and overall survival. Accrual was to be stopped if at 6 months more than 13 disease progressions were observed in 20 patients.

Results

Eighteen (18) progressions occurred at 6 months in the 5-FU-DCT arm. Six-month NPR was 10% (95%CI: 0-23). Six and 12-month survivals were 85% (95%CI: 64-95) and 40% (95%CI: 22-61); median overall survival was 10.1 months. Median progression-free survival was 4.3 months. We report the case of one patient who was amenable to surgery and has been in complete response (CR) for 5.5 years. Toxicities grade ≥ 3 were reported in 75% of patients; no treatment-related death occurred. Severe toxicities were mainly vomiting (35%), abdominal pain (10%) and fatigue (10%).

Conclusions

Combination of 5-FU, docetaxel and radiotherapy has inadequate efficacy in the treatment of LAPC despite good tolerance for the 5-FU-DCT regimen.

Trial Registration

ClinicalTrials.gov: NCT00112697

Targeted in vivo imaging of integrin alphavbeta6 with an improved radiotracer and its relevance in a pancreatic tumor model

The cell surface receptor alpha(v)beta(6) is epithelial specific, and its expression is tightly regulated; it is low or undetectable in adult tissues but has been shown to be increased in many different cancers, including pancreatic, cervical, lung, and colon cancers. Studies have described alpha(v)beta(6) as a prognostic biomarker linked to poor survival. We have recently shown the feasibility of imaging alpha(v)beta(6) in vivo by positron emission tomography (PET) using the peptide [(18)F]FBA-A20FMDV2. Here, we describe improved alpha(v)beta(6) imaging agents and test their efficacy in a mouse model with endogenous alpha(v)beta(6) expression. The modified compounds maintained high affinity for alpha(v)beta(6) and >1,000-fold selectivity over related integrins (by ELISA) and showed significantly improved alpha(v)beta(6)-dependent binding in cell-based assays (>60% binding versus <10% for [(18)F]FBA-A20FMDV2). In vivo studies using either a melanoma cell line (transduced alpha(v)beta(6) expression) or the BxPC-3 human pancreatic carcinoma cell line (endogenous alpha(v)beta(6) expression) revealed that the modified compounds showed significantly improved tumor retention. This, along with good clearance of nonspecifically bound activity, particularly for the new radiotracer [(18)F]FBA-PEG(28)-A20FMDV2, resulted in improved PET imaging. Tumor/pancreas and tumor/blood biodistribution ratios of >23:1 and >47:1, respectively, were achieved at 4 hours. Significantly, [(18)F]FBA-PEG(28)-A20FMDV2 was superior to 2-[(18)F]fluoro-2-deoxy-d-glucose ([(18)F]FDG) in imaging the BxPC-3 tumors. Pancreatic ductal adenocarcinoma is highly metastatic and current preoperative evaluation of resectability using noninvasive imaging has limited success, with most patients having metastases at time of surgery. The fact that these tumors express alpha(v)beta(6) suggests that this probe has significant potential for the in vivo detection of this malignancy, thus having important implications for patient care and therapy.