Analysis of the clinical benefit of intraoperative radiotherapy in patients undergoing macroscopically curative resection for pancreatic cancer

Intraoperative Radiotherapy for Resectable Pancreatic Cancer Using a Low-Energy X-Ray Source: Postoperative Complications and Early Outcomes

PURPOSE

We evaluated the safety, feasibility, and early treatment outcomes of intraoperative radiotherapy (IORT) using a low-energy X-ray source.

MATERIALS AND METHODS

Patients with resectable pancreatic cancer were enrolled in this single-institution, prospective, single-arm, phase II trial. Patients underwent surgery and IORT with 10 Gy prescribed at a 5-mm depth from the tumor bed using a 50 kV X-ray source (Intrabeam, Carl Zeiss). Six cycles of adjuvant gemcitabine-based chemotherapy were administered 8-12 weeks after surgery.

RESULTS

A total of 41 patients were included. Thirty-one patients (75.6%) underwent wide R0 resection, while 5 (12.2%) underwent R1 resection and 5 (12.2%) underwent narrow R0 resection (retroperitoneal margin <1 mm). Grade 3 postoperative complications were reported in only one patient (4.9%) who needed additional surgery due to ulcer perforation. At a median follow-up of 9 months, four patients showed local-only recurrence, nine had distant metastases, and two showed both local and distant recurrence. The 1-year local control rate was 76.4%.

CONCLUSION

Our preliminary report suggests that IORT is well-tolerated and feasible in patients with resectable pancreatic cancer. Further follow-up is needed to confirm the clinical benefits of IORT in terms of local control and overall survival.

TRIAL REGISTRATION

Trial Registration: Clinical trial registration No. (NCT03273374).

Intraoperative Radiation Mitigates the Effect of Microscopically Positive Tumor Margins on Survival Among Pancreatic Adenocarcinoma Patients Treated with Neoadjuvant FOLFIRINOX and Chemoradiation

BACKGROUND

Microscopically positive margins (R1) negatively impact survival in pancreatic ductal adenocarcinoma (PDAC). For patients with close/positive margins, intraoperative radiotherapy (IORT) can improve local control. The prognostic impact of an R1 resection in patients who receive total neoadjuvant therapy (TNT; FOLFIRINOX with chemoradiation) and IORT is unknown.

METHODS

Clinicopathologic data were retrospectively collected for borderline/locally advanced (BR/LA) PDAC patients who received TNT and underwent resection between 2011 and 2019. Disease-free (DFS) and overall survival (OS) measured from time of diagnosis were compared between groups.

RESULTS

Two hundred one patients received TNT and were resected, with a median DFS and OS of 24 months and 47 months, respectively. Eighty-eight patients (44%) received IORT; of these, 69 (78%) underwent an R0 and 19 (22%) an R1 resection. There was no significant difference in clinicopathologic factors between the IORT and no-IORT groups, except for resectability status (LA: IORT 69%, no-IORT 53%, p = 0.021) and surgeons' concern for a positive/close margin. R1 resection was associated with worse DFS and OS in the no-IORT population. However, among patients who received IORT, there was no difference in DFS (R0: 29 months, IQR 14-47 vs R1: 20 months, IQR 15-28; p = 0.114) or OS (R0: 48 months, IQR 25-not reached vs R1: 37 months, IQR 30-47; p = 0.307) between patients who underwent R0 vs R1 resection. In multivariate analysis, within the IORT group, R1 resection was not associated with DFS or OS.

CONCLUSION

IORT may mitigate the adverse effect of an R1 resection on DFS and OS in BR/LA PDAC patients receiving TNT.

The role of intraoperative radiation therapy in resectable pancreatic cancer: a systematic review and meta-analysis

Purpose

Several studies investigating the role of intraoperative radiotherapy (IORT) in the treatment of resectable pancreatic cancer (PC) have been published; however, their results remain inconsistent. By conducting a systematic review and meta-analysis, this study aimed to compare clinical outcomes in patients with resectable PC who underwent surgery with or without IORT.

Methods and materials

The MEDLINE/PubMed, EMBASE, and Cochrane Library databases were searched to identify relevant studies published up to February 28, 2019. The main outcome measures included median survival time (MST), local recurrence (LR), postoperative complications, and operation-related mortality. Pooled effect estimates were obtained by performing a random-effects meta-analysis.

Results

A total of 1095 studies were screened for inclusion, of which 15 studies with 834 patients were included in the meta-analysis. Overall, 401 patients underwent pancreatic resection with IORT and 433 underwent surgery without IORT. The pooled analysis revealed that IORT group experienced favorable overall survival (median survival rate [MSR], 1.20; 95% confidence interval [CI], 1.06–1.37, P = 0.005), compared with patients who did not receive IORT. Additionally, the pooled data showed a significantly reduced LR rate in the IORT group compared with that in the non-IORT group (relative risk [RR], 0.70; 95% CI, 0.51–0.97, P = 0.03). The incidences of postoperative complications (RR, 0.95; 95% CI, 0.73–1.23) and operation-related mortality (RR, 1.07; 95% CI, 0.44–2.63) were similar between the IORT and non-IORT groups.

Conclusion

IORT significantly improved locoregional control and overall survival in patients with resectable PC, without increasing postoperative complications and operation-related mortality rates.

Intraoperative radiotherapy: review of techniques and results

Intraoperative radiotherapy (IORT) is a technique that involves precise delivery of a large dose of ionising radiation to the tumour or tumour bed during surgery. Direct visualisation of the tumour bed and ability to space out the normal tissues from the tumour bed allows maximisation of the dose to the tumour while minimising the dose to normal tissues. This results in an improved therapeutic ratio with IORT. Although it was introduced in the 1960s, it has seen a resurgence of popularity with the introduction of self-shielding mobile linear accelerators and low-kV IORT devices, which by eliminating the logistical issues of transport of the patient during surgery for radiotherapy or building a shielded operating room, has enabled its wider use in the community.

Electrons, low-kV X-rays and HDR brachytherapy are all different methods of IORT in current clinical use. Each method has its own unique set of advantages and disadvantages, its own set of indications where one may be better suited than the other, and each requires a specific kind of expertise.

IORT has demonstrated its efficacy in a wide variety of intra-abdominal tumours, recurrent colorectal cancers, recurrent gynaecological cancers, and soft-tissue tumours. Recently, it has emerged as an attractive treatment option for selected, early-stage breast cancer, owing to the ability to complete the entire course of radiotherapy during surgery. IORT has been used in a multitude of roles across these sites, for dose escalation (retroperitoneal sarcoma), EBRT dose de-escalation (paediatric tumours), as sole radiation modality (early breast cancers) and as a re-irradiation modality (recurrent rectal and gynaecological cancers).

This article aims to provide a review of the rationale, techniques, and outcomes for IORT across different sites relevant to current clinical practice.

Pancreatic Cancer: 80 Years of Surgery-Percentage and Repetitions

Objective. The incidence of pancreatic cancer is estimated to be 48,960 in 2015 in the US and projected to become the second and third leading causes of cancer-related deaths by 2030. The mean costs in 2015 may be assumed to be $79,800 per patient and for each resection $164,100. Attempt is made to evaluate the results over the last 80 years, the number of survivors, and the overall survival percentage. Methods. Altogether 1230 papers have been found which deal with resections and reveal survival information. Only 621 of these report 5-year survivors. Reservation about surgery was first expressed in 1964 and five-year survival of nonresected survivors is well documented. Results. The survival percentage depends not only on the number of survivors but also on the subset from which it is calculated. Since the 1980s the papers have mainly reported the number of resections and survival as actuarial percentages, with or without the actual number of survivors being reported. The actuarial percentage is on average 2.75 higher. Detailed information on the original group (TN), number of resections, and actual number of survivors is reported in only 10.6% of the papers. Repetition occurs when the patients from a certain year are reported several times from the same institution or include survivors from many institutions or countries. Each 5-year survivor may be reported several times. Conclusion. Assuming a 10% resection rate and correcting for repetitions and the life table percentage the overall actual survival rate is hardly more than 0.3%.

Intraoperative radiotherapy for resected pancreatic cancer: a multi-institutional retrospective analysis of 210 patients

PURPOSE

To retrospectively analyze the results of intraoperative radiotherapy (IORT) with or without external beam radiotherapy (EBRT) for resected pancreatic cancer.

METHODS AND MATERIALS

The records of 210 patients treated with gross complete resection (R0: 147 patients; R1: 63 patients) and IORT with or without EBRT were reviewed. One hundred forty-seven patients (70.0%) were treated without EBRT and 114 patients (54.3%) were treated in conjunction with chemotherapy. The median doses of IORT and EBRT were 25 Gy (range, 20-30 Gy) and 45 Gy (range, 20-60Gy), respectively. The median follow-up of the surviving 62 patients was 26.3 months (range, 2.7-90.5 months).

RESULTS

At the time of this analysis, 150 of 210 patients (71.4%) had disease recurrences. Local failure was observed in 31 patients (14.8%), and the 2-year local control rate in all patients was 83.7%. The median survival time and the 2-year actuarial overall survival (OS) in all 210 patients were 19.1 months and 42.1%, respectively. Patients treated with IORT and chemotherapy had a significantly more favorable OS than those treated with IORT alone (p = 0.0011). On univariate analysis, chemotherapy use, degree of resection, carbohydrate antigen 19-9, and pathological N stage had a significant impact on OS and on multivariate analysis; these four factors were significant prognostic factors. Late gastrointestinal morbidity of NCI-CTC Grade 4 was observed in 7 patients (3.3%).

CONCLUSION

IORT yields an excellent local control rate for resected pancreatic cancer with few frequencies of severe late toxicity, and IORT combined with chemotherapy confers a survival benefit compared with that of IORT alone.

Current state of adjuvant therapy in resected pancreatic adenocarcinoma

Pancreatic carcinoma cannot generally be cured by surgery alone. This review summarizes the development of adjuvant therapy over the past two decades. Four randomized controlled trials compare long-term survival of different treatments. The small GITSG-study supports combined chemoradiation, but the EORTC-study found no significant effect. A Norwegian study of adjuvant chemotherapy found an increased median survival, but no effect beyond two years. The large ESPAC-1 study shows a benefit for 5-FU based chemotherapy, while chemoradiation had a negative effect. Thus, evidence favours adjuvant therapy, but 5-FU may not be the ultimate drug. Support for gemcitabine is given by preliminary data from a German randomized trial, and further American and European studies are upcoming. However, postoperative therapy is problematic, as 20-30% of resected patients never undergo treatment because of slow recovery or other reasons. Preoperative therapy has some theoretical advantages, and moreover, patients with rapidly progressive disease may be spared surgery. Randomized controlled trials are lacking, but published results compare well with postoperative, adjuvant therapy. The value of locally targeted therapy is difficult to assess. Reasonable results have been obtained with regional chemotherapy, whereas intraoperative radiotherapy does not seem to increase survival despite reducing reducing local recurrences.

Intraoperative radiation therapy in resected pancreatic carcinoma: long-term analysis

PURPOSE

The combination of external radiotherapy (RT) plus intraoperative radiotherapy (IORT) in patients with pancreatic cancer is still debated. This study presents long-term results (minimum follow-up, 102 months) for 26 patients undergoing integrated adjuvant RT (external RT+IORT).

METHODS AND MATERIALS

From 1990 to 1995, a total of 17 patients with pancreatic cancer underwent IORT (10 Gy) and postoperative external RT (50.4 Gy). Preoperative "flash" RT was included for the last 9 patients. The liver and pancreatic head received 5 Gy (two 2.5-Gy fractions) the day before surgery. In the subsequent period (1996-1998), 9 patients underwent preoperative concomitant chemoradiation (39.6 Gy) with 5-fluorouracil, IORT (10 Gy), and adjuvant chemotherapy.

RESULTS

Preoperative chemoradiation was completed in all patients, whereas postoperative therapy was completed in 13 of 17 patients. All 26 patients underwent pancreatectomy (25 R0 and one R1 resections). One patient died of postoperative complications (3.8%) not related to IORT. The 9 patients undergoing concomitant chemoradiation were candidates for adjuvant chemotherapy; however, only 4 of 9 underwent adjuvant chemotherapy. At last follow-up, 4 patients (15.4%) were alive and disease free. Disease recurrence was documented in 20 patients (76.9%). Sixteen patients (61.5%) showed distant metastasis, and 5 patients (19.2%) showed local recurrence. The incidence of local recurrence in R0 patients was 4 of 25 (16.0%). The overall 5-year survival rate was 15.4%. There was significant correlation with overall survival of tumor diameter (p=0.019).

CONCLUSIONS

The incidence of local recurrence in this long follow-up series (19.2%) was definitely less than that reported in other studies of adjuvant RT (approximately 50%), suggesting a positive impact on local control of integrated adjuvant RT (IORT+external RT).

Early experience with intraoperative radiotherapy in patients with resected pancreatic adenocarcinoma

BACKGROUND

The use of intraoperative radiotherapy (IORT) in patients with resected pancreatic adenocarcinoma has not been clearly defined.

METHODS

The medical records of our first 22 patients receiving IORT for resected pancreatic adenocarcinoma (2001 to 2006) were reviewed and compared with the records of 27 consecutive patients not receiving IORT for resected pancreatic adenocarcinoma (2004 to 2006).

RESULTS

There were no 30-day mortalities in either group, and complication rates were similar. Local recurrence occurred in 18% in the IORT group (median 14 months) and 12% in the no-IORT group (median 7 months). Distant recurrence occurred in 47% in the IORT group (median 11 months) and 32% in the no-IORT group (median 6.5 months). Median overall, stage-specific, and location-specific survival did not differ between the groups.

CONCLUSIONS

Although limited in size and follow-up, our experience showed that complications, recurrence, and survival were not affected by IORT, but time to recurrence may be longer with IORT.

Adjuvant therapy in pancreatic cancer: a critical appraisal

Adenocarcinoma of the pancreas carries a grim prognosis. Surgery is currently the only curative option, but even the few patients undergoing complete resection of early localised disease run a high risk for relapse and death. Although numerous clinical trials have been conducted during the past 20 years to find an effective adjuvant treatment, thus far no general consensus on the most appropriate regimen has been reached. In a small randomised study performed in the 1980s by the GITSG (Gastrointestinal Tumor Study Group), encouraging results were obtained with fluorouracil (5-FU)-based split-course chemoradiotherapy, but these findings were not confirmed in a randomised study initiated some years later by the EORTC (European Organisation for Research and Treatment of Cancer). More recently, the ESPAC (European Study Group for Pancreatic Cancer)-1 trial even indicated a detrimental effect of chemoradiotherapy, while chemotherapy with 5-FU was shown to have a significant positive impact on long-term survival. However, this latter finding is in contrast to earlier studies of adjuvant chemotherapy with 5-FU combinations from Norway and Japan that did not suggest a prolonged beneficial effect of 5-FU on survival. Thus, the results for adjuvant regimens based on systemic 5-FU with or without external radiotherapy are conflicting. Clinical experience with intraoperative radiotherapy or regionally targeted chemotherapy to prevent local relapse, though encouraging, is still preliminary. More recently, gemcitabine, which is the most effective single agent in advanced pancreatic cancer, has also been evaluated in the adjuvant setting. The RTOG (Radiation Therapy Oncology Group)-9704 trial demonstrated that gemcitabine is superior to 5-FU as an addition to chemoradiotherapy, but the results did not allow conclusions about the value of radiation in the combined modality approach. The Charité Onkologie CONKO-001 is a randomised trial from Germany and Austria that compared adjuvant gemcitabine with observation alone. Gemcitabine was very well tolerated and almost doubled median disease-free survival and overall survival rate at 5 years, although the advantage in overall survival failed to reach statistical significance. In summary, the available data from randomised clinical trials of adjuvant therapy suggest that (i) chemoradiotherapy has no obvious advantage compared with chemotherapy alone; and (ii) chemotherapy with gemcitabine is effective and probably offers the best benefit-risk ratio of all currently available adjuvant treatment options.

Chemoradiotherapy in patients with pancreatic carcinoma: phase-I study with a fixed radiation dose and escalating doses of weekly gemcitabine

AIM

The aim of this phase-I study is to determine the maximum tolerated dose (MTD) of weekly gemcitabine in concurrent combination with a total radiation dose of 54 Gy in patients with pancreatic cancer.

METHODS

In all patients, a total dose of 54 Gy was delivered in 30 fractions of 1.8 Gy/day. Gross tumor volume and regional lymph nodes were included in the irradiated volume with a 1- to 1.5-cm margin. The doses of weekly gemcitabine were escalated from 100 mg/m2 by increments of 50 mg/m2. Dose-limiting toxicity (DLT) was defined as hematologic toxicity, prolonged grade-3 non-hematologic toxicity, and incompletion of the planned treatment.

RESULTS

Twenty-six patients entered the trial. From level 1 (100 mg/m2) to level 4 (250 mg/m2), no patient experienced DLT except for 1 patient at level 1. At level 5 (300 mg/m2), 3 of the 5 patients met the DLT criteria. One patient developed severe pulmonary abscess, and the other 2 patients had hematologic DLT. The overall partial response rate was 29%, and the median survival time was 13.7 months. The first relapse occurred at the in-field primary site in 6 patients and at distant organs in 13 patients.

CONCLUSION

The MTD of weekly gemcitabine was 250 mg/m2 in the present chemoradiotherapy setting. The efficacy of this chemoradiotherapy regimen is currently being evaluated in the phase-II setting.

Extrahepatic portal vein occlusion without recurrence after pancreaticoduodenectomy and intraoperative radiation therapy

PURPOSE

Although there are no definitive studies that characterize the survival benefit of intraoperative radiation therapy (IORT), the therapy does not seem to produce significant complication. In our institution, pancreaticoduodenectomy (PD) and IORT are often complicated by the development of extrahepatic portal vein occlusion (EHPO). The aim of this study was to characterize the phenomenon of EHPO after PD and IORT.

METHODS AND MATERIALS

Between September 1992 and December 2001, 107 patients received macroscopic curative PD for periampullary disease in our institution. IORT (radiation dose: 20 Gy) was performed in 53 of these patients. Criteria for diagnosis of EHPO were as follows: (1) computerized tomography findings of occlusive extrahepatic portal vein, (2) symptoms of portal hypertension, and (3) confirmation to exclude tumor recurrence from origin of EHPO, because this study examined whether EHPO was a complication of PD and IORT.

RESULTS

EHPO was diagnosed in 12 patients. Among patient and operative variables, IORT was the only statistically significant factor associated with a diagnosis of EHPO (p = 0.0052). The median developed time to EHPO and overall survival after surgery in EHPO patients were 358 days and 2,562 days, respectively. Eight patients (67%) with EHPO died during the follow-up period. At 5 years after therapy, EHPO was diagnosed in 67% of survivors who had received IORT.

CONCLUSIONS

Patients undergoing IORT and PD have a relatively high incidence of EHPO, and patients who develop postoperative EHPO have poor prognoses.

Conclusions from the European Study Group for Pancreatic Cancer adjuvant trial of chemoradiotherapy and chemotherapy for pancreatic cancer

Pancreatic ductal adenocarcinoma remains one of the most difficult cancers to treat. It is a tumor that tends to present late, and surgical resection is only possible in a minority of patients. After successful surgery, the prognosis is still relatively poor. Attempts at more radical pancreatic resections and extended lymphadenectomy, although feasible without excessive morbidity and mortality, have failed to produce any convincing improvement in survival. During the last few years, therefore, efforts have been directed toward the development of adjuvant therapies in an attempt to improve outcome. This article describes the main trials of adjuvant chemotherapy, chemoradiotherapy, and chemoradiotherapy with follow-on chemotherapy and presents the results of the European Study Group for Pancreatic Cancer (ESPAC) 1 trial and the status of the ESPAC 2 and 3 trials.

Neoadjuvant chemoradiation with tegafur in cancer of the pancreas: initial analysis of clinical tolerance and outcome

The early institutional experience in the neoadjuvant treatment of potentially resectable pancreatic carcinoma using oral Tegafur as radioenhancing agent is analyzed. Fifteen patients (10 male and 5 female, mean age of 61 years) were treated over a 30-month period. Tegafur dose was 1,200 mg/d along the external radiotherapy period (45-55 consecutive days). Preoperative radiotherapy achieved a total dose of 45 to 50 Gy (1.8 Gy/d). Intraoperative electron boost (10-15 Gy) was delivered at the time of surgery. Hematologic tolerance showed a significant decrease of neutrophil and platelet counts from the outset to the end of the neoadjuvant period (p = 0.001 and p = 0.004, respectively). Five grade III vomiting episodes (33%) were also registered. In 9 patients (60%), surgical resection was performed after chemoradiation. Three complete pathologic responses (pT0 specimens) were identified; in seven cases, the resection achieved tumor-free surgical margins of the specimen. With a median follow-up of 21 months, median survival time was 17 months, with actuarial rates of 45% at 1 year and 24% at 3 years. Median survival for the resected patients was 23 months, and for the unresected patients median survival was 8 months (p = 0.02). The overall median survival in completely resected patients was 28 months, with a 71% survival rate at 1 and 3 years. It is concluded that the treatment scheme described is feasible and acceptably tolerated. The use of oral Tegafur seems to induce results similar to those of other therapeutic protocols using intravenous radioenhancing chemotherapy.

Effect of intraoperative radiotherapy combined with external beam radiotherapy following internal drainage for advanced pancreatic carcinoma

AIM: To determine the survival of advanced pancreatic cancer patients treated with intraoperative radiotherapy (IORT) combined with external beam radiation therapy (EBRT) following internal drainage (cholecystojejunostomy or choledochojejunostomy).

METHODS: Eighty-one patients with advanced pancreatic cancer who received IORT combined with EBRT following internal drainage (ID) between 1996 and 2001 were retrospectively analyzed. Among the 81 patients, 18 underwent ID + IORT, 25 ID + IORT + EBRT (meanwhile, given 5-Fu 300 mg/m² iv drip, 2f/w), 16 EBRT, 22 had undergone simple internal drainage. The IORT dose was 15-25Gy in a single fraction. The usual EBRT dose was 30-40Gy with a daily fraction of 1.8-2.0 Gy.

RESULTS: The complete remission rate, partial remission rate of patients with backache and abdominal pain treated with ID + IORT were 55.5%, 33.3% respectively. Alleviation of pain was observed 2 or 3 wk after IORT. The median survival time (MST) of ID + IORT group was 10.7 mo. The pain remission rate of patients treated with ID + IORT + EBRT was 92%, and their MST was 12.2 mo. The MST of patients treated with EBRT and simple internal drainage was 5.1 mo and 7.0 mo, respectively. The survival curve of ID + IORT group and ID + IORT + EBRT group was significantly better than that of EBRT group (P < 0.05). The difference between the ID + IORT + EBRT group and ID group was significant (P < 0.05).

CONCLUSION: IORT combined with EBRT following internal drainage can alleviate pain, improve quality of life and prolong survival time of patients with advanced pancreatic cancer.

Adjuvant therapy in pancreatic cancer: historical and current perspectives

The results from pancreatic ductal adenocarcinoma appear to be improving with increased resection rates and reduced postoperative mortality reported by specialist pancreatic cancer teams. Developments with medical oncological treatments have been difficult, however, due to the fundamentally aggressive biological nature of pancreatic cancer and its resistance to chemotherapy coupled with a relative dearth of randomised controlled trials. The European Study Group for Pancreatic Cancer (ESPAC)-1 trial recruited nearly 600 patients and is the largest trial in pancreatic cancer. The results demonstrated that the current best adjuvant treatment is chemotherapy using bolus 5-fluorouracil with folinic acid. The median survival of patients randomly assigned to chemoradiotherapy was 15.5 months and is comparable with many other studies, but the median survival in the chemotherapy arm was 19.7 months and is as good or superior to multimodality treatments including intra-operative radiotherapy, adjuvant chemoradiotherapy and neo-adjuvant therapies. The use of adjuvant 5-fluorouracil with folinic acid may be supplanted by gemcitabine but requires confirmation by ongoing clinical trials, notably ESPAC-3, which plans to recruit 990 patients from Europe, Canada and Australasia. Major trials such as ESPAC-1 and ESPAC-3 have set new standards for the development of adjuvant treatment and it is now clear that such treatment in this field has the potential to significantly improve both patient survival and quality of life after curative resection.

Impact of intraoperative radiation on postoperative and disease-specific outcome after pancreatoduodenectomy for adenocarcinoma: a propensity score analysis

For periampullary cancer,intraoperative radiation therapy (IORT) administered to the site with the highest locoregional recurrence risk carries the rationale to improve tumor control. An IORT effect on survival remains unclear. IORT impact on postoperative outcomes after pancreatectomy for adenocarcinoma was analyzed, with a specific attempt to correct for the nonrandom IORT treatment assignment, and to account for treatment group imbalances in the interpretation of outcome differences. A propensity-score-adjusted analysis, based on variable selection by logistic regression, was used to rebalance treatments. Between 1989 and 1999, 61 patients underwent partial or total pancreatectomy for a primary periampullary adenocarcinoma at the City of Hope National Medical Center. Diagnoses included pancreatic (n = 36), duodenal (n = 11), ampullary (n = 10), and bile duct cancer (n = 4). Thirty patients received IORT to the resection area, with a median dose of 15 Gy (range: 10-20), followed by postoperative external beam radiation (n = 24). Mortality was 0%, the complication rate 61%. Of 33 patients with a documented recurrence, 6 had an isolated locoregional recurrence only (1 IORT versus 5 no IORT, = 0.05); the systemic recurrence pattern differed as well (IORT 94%, no IORT 67%; = 0.04). IORT had no significant impact on hospital stay (overall median: 17 days), disease-free survival (16 months), and overall survival (23 months) when adjusted for those most relevant variables reflecting IORT treatment group assignment propensity. After adjustment for relevant propensity factors, IORT was not linked to a significantly increased risk for complications, hospital stay, or survival hazard. The recurrence pattern may be affected in some patients, but systemic recurrences predominate. We continue to explore IORT in combination with systemic chemotherapy.

Adjuvant radiotherapy in resectable pancreatic carcinoma

AIM

Pancreatic cancer is a near fatal disease. External beam radiotherapy and intraoperative radiation therapy (IORT) has been proposed with the aim to improve clinical outcome in resectable tumors. The aim of this study is to assess the feasibility and outcome in patients with cT1-3 pancreatic cancer, treated with surgery, external beam radiotherapy and IORT.

METHODS

From 1990 to 1996, 17 patients with clinical stage T1-3N0-1M0 adenocarcinoma of the head of the pancreas were treated with pancreatectomy and pre- (nine patients: 5 Gy), intra- (all patients: 10 Gy) and post-operative (all patients: 50 Gy) radiotherapy. The pathologic T stages were: 4 pT2 and 13 pT3. The pathologic N stages were: 9 pN0 and 8 pN1. Minimum follow-up in living patients was 60 months.

RESULTS

No perioperative mortalities were recorded. Two patients showed postoperative morbidity (11.8%) which required a subsequent laparotomy. The disease-free survival at 1, 3 and 5 years was 41, 23 and 18%, respectively (median: 9 months). The overall survival at 1, 3 and 5 years was 70%, 41% and 18%, respectively (median: 17.5 months). Three patients developed local failure (17.6%) and 12 patients showed distant metastases (70.6%). Univariate analysis (logrank) showed: a significant correlation between both N-stage and retroperitoneal involvement (RPI) with local control (N-stage: P=0.0155; RPI:P =0.0295), a significant correlation between maximum tumor size and metastases-free survival (P=0.0167) and overall survival (P=0.0241); the female gender was another predictor of prolonged survival (P= 0.0465). Multivariate analysis (Cox) showed a significant impact of N-stage and retroperitoneal involvement on local control and also a significant correlation between perineural involvement and tumor diameter with metastases-free survival.

CONCLUSIONS

These results are similar to those of other published series and suggest that this approach is feasible with acceptable local control and survival, especially in patients with small tumors (<2.5 cm: 5 year survival=33.3%) and in female patients (5 year survival=30%). Due to the impact of gender, tumor diameter and N stage on prognosis, in the design of future trials a stratification of patients based on these categories should be considered. The search of effective chemotherapeutic agents is required, to reduce the high incidence of distant metastases, especially in larger tumors.