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

Long-term results of intraoperative electron beam radiation therapy for nonmetastatic locally advanced pancreatic cancer: Retrospective cohort study, 7-year experience with 247 patients at the National Cancer Center in China

To assess prognostic benefits of intraoperative electron beam radiation therapy (IOERT) in patients with nonmetastatic locally advanced pancreatic cancer (LAPC) and evaluate optimal adjuvant treatment after IOERT.A retrospective cohort study using prospectively collected data was conducted at the Cancer Hospital of the Chinese Academy of Medical Sciences, China National Cancer Center.Two hundred forty-seven consecutive patients with nonmetastatic LAPC who underwent IOERT between January 2008 and May 2015 were identified and included in the study. Overall survival (OS) was calculated from the day of IOERT. Prognostic factors were examined using Cox proportional hazards models. The 1-, 2-, and 3-year actuarial survival rates were 40%, 14%, and 7.2%, respectively, with a median OS of 9.0 months. On multivariate analysis, an IOERT applicator diameter < 6 cm (hazards ratio [HR], 0.67; 95% confidence interval [CI], 0.47-0.97), no intraoperative interstitial sustained-release 5-fluorouracil chemotherapy (HR, 0.46; 95% CI, 0.32-0.66), and receipt of postoperative chemoradiotherapy followed by chemotherapy (HR, 0.11; 95% CI, 0.04-0.25) were significantly associated with improved OS. Pain relief after IOERT was achieved in 111 of the 117 patients, with complete remission in 74 and partial remission in 37. Postoperative complications rate and mortality were 14.0% and 0.4%, respectively. Nonmetastatic LAPC patients with smaller size tumors could achieve positive long-term survival outcomes with a treatment strategy incorporating IOERT and postoperative adjuvant treatment.Chemoradiotherapy followed by chemotherapy might be a recommended adjuvant treatment strategy for well-selected cases. Intraoperative interstitial sustained-release 5-fluorouracil chemotherapy should not be recommended for patients with nonmetastatic LAPC.

Orthovoltage intraoperative radiation therapy for pancreatic adenocarcinoma

Purpose

To analyze the outcomes of patients from a single institution treated with surgery and orthovoltage intraoperative radiotherapy (IORT) for pancreatic adenocarcinoma.

Methods

We retrospectively reviewed 23 consecutive patients from 1990-2001 treated with IORT to 23 discrete sites with median and mean follow up of 6.5 and 21 months, respectively. Most tumors were located in the head of the pancreas (83%) and sites irradiated included: tumor bed (57%), vessels (26%), both the tumor bed/vessels (13%) and other (4%). The majority of patients (83%) had IORT at the time of their definitive surgery. Three patients had preoperative chemoradiation (13%). Orthovoltage X-rays (200-250 kVp) were employed via individually sized and beveled cone applicators. Additional mean clinical characteristics include: age 64 (range 41-81); tumor size 4 cm (range 1.4-11); and IORT dose 1106 cGy (range 600-1500). Post-operative external beam radiation (EBRT) or chemotherapy was given to 65% and 76% of the assessable patients, respectively. Outcomes measured were infield control (IFC), loco-regional control (LRC), distant metastasis free survival (DMFS), overall survival (OS) and treatment-related complications.

Results

Kaplan-Meier (KM) 2-year IFC, LRC, DMFS and OS probabilities for the whole group were 83%, 61%, 26%, and 27%, respectively. Our cohort had three grade 3-5 complications associated with treatment (surgery and IORT).

Conclusions

Orthovoltage IORT following tumor reductive surgery is reasonably well tolerated and seems to confer in-field control in carefully selected patients. However, distant metastases remain the major problem for patients with pancreatic adenocarcinoma.

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.

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.

Extent of lymph node retrieval and pancreatic cancer survival: information from a large US population database

BACKGROUND

Operative therapy of pancreatic cancer is associated with poor survival because of high recurrence rates after pancreatectomy. The effect of lymph node (LN) dissection on survival continues to be debated.

METHODS

A pancreatic cancer data set was created through structured queries to the Surveillance, Epidemiology, and End Results 1973 to 2000 database. Stage information was created according to 6th edition American Joint Committee on Cancer tumor-node-metastasis criteria, and the effect of LN number on survival was analyzed.

RESULTS

Out of a cohort of 20,631 patients with carcinomas of the exocrine pancreas, surgical details were available for 2,787 patients. Procedures included pancreatoduodenectomies (n = 1848; 66%), radical regional pancreatectomies (n = 516; 19%), other partial resections (n = 316; 11%), and total pancreatectomies (n = 107; 4%). For 1666 of these patients with complete clinicopathologic information, the median age was 66 years (range, 22-96 years), with an equal sex ratio. The median number of total LNs examined was 7 (range, 1-52), of positive LNs was 1 (range, 0-34), and of negative LNs was 6 (range, 0-30). Multivariate survival analysis yielded these prognostic variables: number of LNs examined, number of positive LNs, tumor size, extrapancreatic extension, radiotherapy (all P < .0001), and age (P = .0009). The greatest survival differences were observed for negative LN counts of 10 to 15.

CONCLUSIONS

Stage-based survival prediction of pancreatic cancer is strongly influenced by total LN counts and numbers of negative LNs obtained. Although the mechanism remains unclear and could reflect confounding factors (margin status and institutional volume), an attempt to resect and examine at least 15 LNs to yield preferably between 10 and 15 negative LNs seems sensible for curative-intent pancreatectomy.

A review of the application of propensity score methods yielded increasing use, advantages in specific settings, but not substantially different estimates compared with conventional multivariable methods

OBJECTIVE

Propensity score (PS) analyses attempt to control for confounding in nonexperimental studies by adjusting for the likelihood that a given patient is exposed. Such analyses have been proposed to address confounding by indication, but there is little empirical evidence that they achieve better control than conventional multivariate outcome modeling.

STUDY DESIGN AND METHODS

Using PubMed and Science Citation Index, we assessed the use of propensity scores over time and critically evaluated studies published through 2003.

RESULTS

Use of propensity scores increased from a total of 8 reports before 1998 to 71 in 2003. Most of the 177 published studies abstracted assessed medications (N=60) or surgical interventions (N=51), mainly in cardiology and cardiac surgery (N=90). Whether PS methods or conventional outcome models were used to control for confounding had little effect on results in those studies in which such comparison was possible. Only 9 of 69 studies (13%) had an effect estimate that differed by more than 20% from that obtained with a conventional outcome model in all PS analyses presented.

CONCLUSIONS

Publication of results based on propensity score methods has increased dramatically, but there is little evidence that these methods yield substantially different estimates compared with conventional multivariable methods.

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.

A study of radiotherapy modalities combined with continuous 5-FU infusion for locally advanced gastrointestinal malignancies

AIM

We describe the feasibility of combining infusional 5-fluorouracil (5-FU) with intraoperative radiation therapy (IORT).

METHODS

Patients with surgically resectable locally advanced gastrointestinal cancers were treated concurrently during surgery with IORT and a 72 h infusion of 5-FU. Patients without previous external beam radiation therapy (EBRT) were subsequently treated with EBRT (40-50Gy) concurrent with a 21-day continuous infusion of 5-FU. Pancreatic, gastric, duodenal, ampullary, recurrent colorectal, and recurrent anal cancer were included.

RESULTS

During IORT/5-FU, no chemotherapy-related grade III or IV hematologic or gastrointestinal toxicity was noted. Post-surgical recovery or wound healing was not affected. One of nine patients who received post-operative radiation required a treatment break. During follow-up, there were more complications in patients with pelvic tumours, especially those with previous radiation. Nine patients have had local and/or local regional recurrences, two of these in the IORT field.

CONCLUSIONS

Treatment with a combination of IORT and 5-FU followed by EBRT and 5-FU is feasible. However, long-term complications may be increased in previously irradiated recurrent pelvic tumours.

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.