Comparison of four target volume definitions for pancreatic cancer. Guidelines for treatment of the lymphatics and the primary tumor

The ERBB receptor inhibitor dacomitinib suppresses proliferation and invasion of pancreatic ductal adenocarcinoma cells

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC), the most common malignancy of the pancreas, is the fourth most common cause of cancer-related death in the USA. Local progression, early tumor dissemination and low efficacy of current treatments are the major reasons for its high mortality rate. The ERBB family is over-expressed in PDAC and plays essential roles in its tumorigenesis; however, single-targeted ERBB inhibitors have shown limited activity in this disease. Here, we examined the anti-tumor activity of dacomitinib, a pan-ERBB receptor inhibitor, on PDAC cells.

METHODS

Anti-proliferative effects of dacomitinib were determined using a cell proliferation assay and crystal violet staining. Annexin V/PI staining, radiation therapy and cell migration and invasion assays were carried out to examine the effects of dacomitinib on apoptosis, radio-sensitivity and cell motility, respectively. Quantitative reverse transcription-PCR (qRT-PCR) and Western blot analyses were applied to elucidate the molecular mechanisms underlying the anti-tumor activity of dacomitinib.

RESULTS

We found that dacomitinib diminished PDAC cell proliferation via inhibition of FOXM1 and its targets Aurora kinase B and cyclin B1. Moreover, we found that dacomitinib induced apoptosis and potentiated radio-sensitivity via inhibition of the anti-apoptotic proteins survivin and MCL1. Treatment with dacomitinib attenuated cell migration and invasion through inhibition of the epithelial-to-mesenchymal transition (EMT) markers ZEB1, Snail and N-cadherin. In contrast, we found that the anti-tumor activity of single-targeted ERBB agents including cetuximab (anti-EGFR mAb), trastuzumab (anti-HER2 mAb), H3.105.5 (anti-HER3 mAb) and erlotinib (EGFR small molecule inhibitor) were marginal.

CONCLUSIONS

Our findings indicate that dacomitinib-mediated blockade of the ERBB receptors yields advantages over single-targeted ERBB inhibition and provide a rationale for further investigation of the therapeutic potential of dacomitinib in the treatment of ERBB-driven PDAC.

Respiratory motion of lymph node stations in pancreatic cancer: Analyses using contrast-enhanced four-dimensional computed tomography

BACKGROUND AND PURPOSE

Data regarding respiratory motion of lymph node (LN) stations in pancreatic cancer is limited. Therefore, we assessed their respiratory motion using contrast-enhanced four-dimensional-computed tomography (CE-4DCT).

MATERIAL AND METHODS

We evaluated respiratory motion in 18 pancreatic cancer patients. We selected LN stations around major arteries which were visible on CE-4DCT images. This included the common hepatic, celiac, splenic, and superior mesenteric stations. Two radiation oncologists individually delineated the gross tumor volume (GTV) and the LN stations as observers 1 and 2.

RESULTS

The respiratory motion of the celiac (median, 3.9 mm each for both observers) and superior mesenteric (median, 4.5 and 5.0 mm for observers 1 and 2, respectively) stations in the craniocaudal (CC) directions was significantly smaller than that of the GTV (median, 8.9 and 7.8 mm for observers 1 and 2, respectively). The respiratory motion of the common hepatic station (median, 3.8 and 3.6 mm for observers 1 and 2, respectively) in the anterior-posterior (AP) direction was significantly larger than that of the GTV (median, 2.8 and 2.2 mm for observers 1 and 2, respectively).

CONCLUSIONS

We observed significant differences in respiratory motion between the GTV and the LN stations in pancreatic cancer.

Endobiliary Stent Position Changes during External-beam Radiotherapy

PURPOSE

Endobiliary stents can be used as surrogates for pancreatic localization when using cone-beam computed tomography (CBCT) during external-beam radiotherapy (EBRT). This work reports on interfraction stent position changes during EBRT for locally advanced pancreatic cancer (LAPC).

MATERIALS AND METHODS

Six patients with endobiliary stents who underwent EBRT for LAPC were assessed. Measurements from the most superior aspect of the stent (sup stent) and the most inferior aspect of the stent (inf stent) to the most inferior, posterior aspect of the L1 vertebra central spinous process were determined from daily treatment CBCTs and compared with those determined from the planning computed tomography (CT) scan. Changes in stent-L1 measurements were interpreted as changes in relative stent position.

RESULTS

Three patients showed mean interfraction stent position changes of ≥1 cm when treatment measurements were compared with planning measurements. The sup stent for patient A moved to the right (2.66 ± 2.77 cm) and inferiorly (3.0 ± 3.12 cm), and the inf stent moved to the right (1.92 ± 2.02 cm) inferiorly (3.23 ± 3.34 cm) and posteriorly (1.41 ± 1.43 cm). The inf stent for patient B moved superiorly (2.23 ± 0.49 cm) and posteriorly (1.72 ± 0.59 cm). The sup and inf stent for patient F moved inferiorly (0.98 ± 0.35 cm and 1.21 ± 0.38 cm, respectively). The remaining three patients C, D, and E showed interfraction position changes of <1 cm.

CONCLUSION

Endobiliary stent migration and deformation were observed in a small subset of patients. Further investigation is required before confirming their use as surrogates for LAPC target localization during image-guided EBRT.

Role of radiotherapy in the chemotherapy-containing multidisciplinary management of patients with resected pancreatic adenocarcinoma

BACKGROUND

To analyze prognostic factors associated with long-term outcomes in patients with resected pancreatic cancer treated with chemotherapy (CT) and surgery with or without external beam radiotherapy (EBRT).

PATIENTS AND METHODS

From January 1995 to December 2012, 95 patients with adenocarcinoma of the pancreas and locoregional disease [clinical stage IB-IIA (n = 45; 47%), IIB-IIIC (n = 50; 53%)] were treated with curative resection [R0 (n = 52; 55%), R1 (n = 43, 45%)] and CT with (n = 60; 63%) or without (n = 35; 37%) EBRT (45-50.4 Gy). Additionally, 29 patients (48%) also received a pre-anastomosis IOERT boost (applicator diameter size, 7-10 cm; dose, 10-15 Gy; beam energy, 9-18 MeV).

RESULTS

With a median follow-up of 17.2 months (range, 1-182), 2-year overall survival (OS), disease-free survival (DFS), and locoregional control were 28, 20, and 53%, respectively. Univariate analyses showed that IIB-IIIC stage (HR, 2.23; p = 0.04), R1 margin resection status (HR, 2.09; p = 0.04), no vascular resection (HR, 0.42; p = 0.02), and not receiving external beam radiotherapy (HR, 2.70; p = 0.004) were associated with locoregional recurrence. In the multivariate analysis, only R1 margin resection status (HR, 2.63; p = 0.009) and not receiving EBRT (HR, 2.91; p = 0.002) retained significance with regard to locoregional recurrence. We observed no difference in toxicity between patients treated with or without EBRT (p = 0.44). Overall treatment mortality was 3%. No long-term treatment-related death occurred.

CONCLUSIONS

Although adjuvant CT is still the standard of care for resected pancreatic tumors, OS remains modest owing to the high risk of distant metastases. Locoregional treatment needs to be tested in the context of more efficient systemic therapy.

Neoadjuvant chemoradiation therapy with gemcitabine/cisplatin and surgery versus immediate surgery in resectable pancreatic cancer: results of the first prospective randomized phase II trial

Background

In nonrandomized trials, neoadjuvant treatment was reported to prolong survival in patients with pancreatic cancer. As neoadjuvant chemoradiation is established for the treatment of rectal cancer we examined the value of neoadjuvant chemoradiotherapy in pancreatic cancer in a randomized phase II trial. Radiological staging defining resectability was basic information prior to randomization in contrast to adjuvant therapy trials resting on pathological staging.

Patients and methods

Patients with resectable adenocarcinoma of the pancreatic head were randomized to primary surgery (Arm A) or neoadjuvant chemoradiotherapy followed by surgery (Arm B), which was followed by adjuvant chemotherapy in both arms. A total of 254 patients were required to detect a 4.33-month improvement in median overall survival (mOS).

Results

The trial was stopped after 73 patients; 66 patients were eligible for analysis. Twenty nine of 33 allocated patients received chemoradiotherapy. Radiotherapy was completed in all patients. Chemotherapy was changed in 3 patients due to toxicity. Tumor resection was performed in 23 vs. 19 patients (A vs. B). The R0 resection rate was 48 % (A) and 52 % (B, P = 0.81) and (y)pN0 was 30 % (A) vs. 39 % (B, P = 0.44), respectively. Postoperative complications were comparable in both groups. mOS was 14.4 vs. 17.4 months (A vs. B; intention-to-treat analysis; P = 0.96). After tumor resection, mOS was 18.9 vs. 25.0 months (A vs. B; P = 0.79).

Conclusion

This worldwide first randomized trial for neoadjuvant chemoradiotherapy in pancreatic cancer showed that neoadjuvant chemoradiation is safe with respect to toxicity, perioperative morbidity, and mortality. Nevertheless, the trial was terminated early due to slow recruiting and the results were not significant. ISRCTN78805636; NCT00335543.

Electronic supplementary material

The online version of this article (doi: 10.1007/s00066-014-0737-7) contains supplementary material, which is available to authorized users.