Results of a pooled analysis of IOERT containing multimodality treatment for locally recurrent rectal cancer: Results of 565 patients of two major treatment centres

OBJECTIVE

Aim of this study is analysing the pooled results of Intra-Operative Electron beam Radiotherapy (IOERT) containing multimodality treatment of locally recurrent rectal cancer (LRRC) of two major treatment centres.

METHODS AND MATERIALS

Five hundred sixty five patients with LRRC who underwent multimodality-treatment up to 2010 were studied. The preferred treatment was preoperative chemo-radiotherapy, surgery and IOERT. In uni- and multivariate analyses risk factors for local re-recurrence, distant metastasis free survival, relapse free survival, cancer-specific survival and overall survival were studied.

RESULTS

Two hundred fifty one patients (44%) underwent a radical (R0) resection. In patients who had no preoperative treatment the R0 resection rate was 26%, and this was 43% and 50% for patients who respectively received preoperative re-(chemo)-irradiation or full-course radiotherapy (p < 0.0001). After uni- and multivariate analysis it was found that all oncologic parameters were influenced by preoperative treatment and radicality of the resection. Patients who were re-irradiated had a similar outcome compared to patients, who were radiotherapy naive and could undergo full-course treatment, except the chance of local re-recurrence was higher for re-irradiated patients. Waiting-time between preoperative radiotherapy and IOERT was inversely correlated with the chance of local re-recurrence, and positively correlated with the chance of a R0 resection.

CONCLUSIONS

R0 resection is the most important factor influencing oncologic parameters in treatment of LRRC. Preoperative (chemo)-radiotherapy increases the chance of achieving radical resections and improves oncologic outcomes. Short waiting-times between preoperative treatment and IOERT improves the effectiveness of IOERT to reduce the chance of a local re-recurrence.

Multimodality therapy including surgical resection (SR) and intraoperative electron radiotherapy (IOERT) for locoregionally recurrent (LRR) or advanced primary malignancies of the urinary bladder (UB) or ureter

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Background: For patients (pts) with LRR or advanced primary tumors of the UB or ureter, limited therapeutic options exist. Outcomes of combined SR and IOERT are reported here.

Methods: From 1983 to 2009, a total of 17 pts with urothelial (16 pts) or squamous cell carcinoma (1 pt) of the UB (n=13) or ureter (n=4) were treated with SR and IOERT. Pts had LRR after radical cystoprostatectomy or nephroureterectomy (n=15) or advanced primary tumor (n=2). Extent of SR was R0 (microscopic negative margins), R1 (microscopic positive margins), and R2 (gross residual tumor) in 7, 1, and 9 pts, respectively. After maximal SR, IOERT was delivered to the tumor bed. Median IOERT dose and energy delivered were 12.5 Gy (range; 10-20) and 9 MeV (range; 6-18), respectively, with 1 (n=15), 2 (n=1), or 3 (n=1) IOERT fields. Sixteen pts also received perioperative external beam radiotherapy (EBRT) with a median dose of 50.4 Gy (range; 21.6- 60). Five pts received concurrent chemotherapy (CT) with perioperative EBRT. Overall (OS), disease-free survival (DFS) and relapse patterns were estimated from the date of SR and IOERT using the Kaplan-Meier method.

Results: The median pt age was 63 years (yrs) (range; 51-76). The median follow-up of surviving pts was 3.6 yrs (range; 1.1-10.0). OS and DFS at 1, 2, and 5 yrs were 53%, 31%, and 16%, and 24%, 18%, and 18%, respectively. Central (within the IOERT field), locoregional (tumor bed or first echelon draining lymphatics), and distant relapse at 2 yrs were 15%, 49%, and 67%, respectively. Seven pts received systemic CT after relapse. Mortality within 30 days of SR and IOERT was 0%. Two pts (12%) experienced grade 4-5 (NCI-CTCAE v. 4) toxicity potentially related to the multimodality therapy.

Conclusions: For pts with LRR or advanced primary tumor of the UB or ureter, this multimodality therapy including SR and IOERT resulted in durable OS and DFS in a small but significant number of pts. Both LRR and distant relapse were common, indicating a need for more effective systemic therapy along with more refined locoregional therapy.

No significant financial relationships to disclose.

Long-term update of U.S. GI Intergroup RTOG 98-11 phase III trial for anal carcinoma: Comparison of concurrent chemoradiation with 5FU-mitomycin versus 5FU-cisplatin for disease-free and overall survival

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Background: On initial publication of GI Intergroup RTOG 98-11, concurrent chemoradiation with 5FU+mitomycin (MMC) decreased colostomy failure (CF) vs induction plus concurrent 5FU+cisplatin (CDDP), but did not significantly impact disease free or overall survival (DFS, OS). The intent of the current analysis is to determine the long-term impact of treatment on survival (DFS, OS, colostomy-free [CFS]), CF and relapse (local-regional [LRF], distant [DM]) in this patient group.

Methods: Stratification factors included gender, clinical node status, and primary size. DFS/OS were estimated univariately by Kaplan-Meier method and treatment arms compared by log-rank test. Time to relapse/CF were estimated by cumulative incidence method and treatment arms compared by Gray's test. Multivariate analyses were done with Cox proportional hazard models to test for treatment differences, adjusting for stratification factors.

Results: Of 682 patients accrued, 649 were analyzable for outcomes. As seen in the table, 5-yr DFS and OS were statistically better for RT+5FU/MMC vs RT+5FU/CDDP (67.7 v 57.6%, p=.0.0045; 78.2 v 70.5%, p=0.021) with trends toward statistical significance for CFS, LRF, and CF (71.8 v 64.9%, p=0.053; 20 v 26.5%, 11.9 v 17.3%, p=0.092 and 0.075). Similar results were seen in multivariate analysis.

Conclusions: Concurrent chemoradiation with 5FU-MMC has a statistically significant impact on DFS and OS vs induction + concurrent 5FU-CDDP and borderline significance for CFS, CF and LRF. Therefore, RT+5FU/MMC remains the preferred standard of care. Potential strategies to improve outcomes include treatment intensification and individualized molecular-based treatment. Supported by RTOG grant U10 CA21661 and CCOP grant U10 CA37422 from the National Cancer Institute (NCI).

[Table: see text]

No significant financial relationships to disclose.

Ratio of metastatic to examined lymph nodes is a powerful predictor of overall survival in rectal cancer: An analysis of Intergroup 0114

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Background: Lymph node (LN) metastasis is associated with decreased survival in rectal cancer. It has been suggested that at least 14 LN be evaluated for adequate staging. However, a large percentage of patients have fewer than the recommended number of LN examined. We hypothesized that LN ratio would be predictive of overall survival in rectal cancer. Methods: Data was analyzed from Intergroup 0114, a mature trial of postoperative adjuvant chemotherapy and radiation in T3/4 and/or LN positive rectal cancer. Survival was the same for all arms allowing the entire group to be considered as one. The primary endpoint evaluated was overall survival. A proportional hazards model was used to determine the relative prognostic impact of LN ratio compared to number of LN examined, number of positive LN, number of negative LN and AJCC nodal stage. LN ratio was defined as the number of positive LN divided by the total number of LN examined. Four groups were analyzed based on proportion of positive LN: =0.25, >0.25–0.50, >0.50–0.75 and >0.75. Results: 1,648 patients were evaluable. There were 251 T1/2, 1,251 T3 and 146 T4 tumors. 513 patients were N0, 743 N1 and 392 N2. Median number of LN was 9. LN ratio was predictive of 5-year overall survival with rates of 0.71, 0.56, 0.50 and 0.43 respectively when analyzed by quartile (p<0.0001). LN ratio remained significant when overall survival was analyzed by number of LN examined and grouped into <10, <15 and >15 nodes evaluated (p<0.0001 for all). LN ratio also predicted overall survival in N1 (p=0.04) and N2 (p=0.0002) disease. When comparing LN ratio (χ2=79.5, p<0.0001) to number of LN examined (χ2=4.7, p=0.03), number of positive LN (χ2=38, p<0.0001), number of negative LN (χ2=32, p<0.0001) and AJCC nodal stage (χ2=55.5, p<0.0001), LN ratio appears to be the strongest predictor of overall survival. Conclusion: LN ratio predicts overall survival in patients with resected rectal cancer. Importantly, this is true in patients who have had a small number of LN evaluated, in addition to those with a large number of LN examined. LN ratio also appears to be a stronger predictor of overall survival than other described LN prognostic factors. LN ratio may be a useful variable to stratify outcome in patients with node-positive rectal cancer.

No significant financial relationships to disclose.

Intraoperative radiotherapy for treatment of locally advanced and recurrent esophageal and gastric adenocarcinomas

Intraoperative radiotherapy (IORT) allows delivery of radiotherapy doses in excess of those typically deliverable with conventional external beam radiotherapy. IORT has potential utility in clinical situations, such as treatment of esophageal and gastric malignancies, in which the radiation tolerance of normal organs limits the dose that can be given with conventional radiotherapy techniques. We reviewed the records of 50 patients who received IORT for locally advanced primary or recurrent gastric or esophageal adenocarcinomas deemed unresectable for cure. IORT was given as a single fraction of electron beam radiotherapy (10-25 Gy) after maximal tumor resection: R0 in 42%, R1 in 46%, and R2 in 12%. Forty-eight patients also received external beam radiotherapy (8-55 Gy), 46 received radiosensitizing chemotherapy, and nine received systemic chemotherapy after radiotherapy. Outcomes were estimated with Kaplan-Meier analysis. Median survival was 1.6 years. Overall survival at 1, 2, and 3 years was 70%, 40%, and 27%. Of 42 patients who died, 37 died from cancer progression and three from multifactorial treatment toxicity. Median survival for patients with recurrent disease versus primary disease was 3.0 years versus 1.3 years (P < 0.05), with a delay of metastatic failure in patients with recurrent tumors (P = 0.06). At 3 years, distant metastatic failure was 79%, local failure was 10%, and regional failure was 15%. IORT for locally advanced primary or recurrent gastric malignancies effectively decreases the risk of local failure. For patients with isolated local recurrences, IORT may be effective salvage therapy. However, more effective systemic therapy is needed as a component of treatment.

Sphincter-preserving radiation therapy for rectal cancer: a simulation study using three-dimensional computerized technology

BACKGROUND

The acquisition of detailed computerized tomography (CT) imaging at the time of simulation, along with three-dimensional (3D) treatment planning software has been integrated with radiation delivery hardware to create the modality known as 3D conformal radiotherapy (3DXRT). This approach provides, in theory, a means to selectively subtract the anal sphincter from the high-dose field of irradiation in patients with stage II and III adenocarcinomas of the mid-rectum scheduled for low anterior resection (LAR).

HYPOTHESIS

Implementation of 3DXRT with sphincter blocking may be a feasible strategy to reduce the dose of radiation distributed to the anal canal without reduction in the dose distribution to the gross tumour volume (GTV) plus adequate margins.

METHODS

Pretreatment simulation CT scans of 10 patients with rectal cancers located between 5 and 10 cm from the anal verge were retrieved from a computerized database. Radiation oncologists and colorectal surgeons defined the contours of the GTV and the anal sphincter, respectively, on successive CT scan slices. These contours provided the volumetric data required to quantify dose distribution and compute dose-volume histograms. The standard mode of pelvic irradiation planned with CT simulation was compared with a 'virtual CT simulation' approach, in which a sphincter block was added to the protocol.

RESULTS

The mean distance of tumours from the anal verge was 6.3 cm. In the virtual simulation treatment plan, a 2-cm margin separated the sphincter block from the lower limit of the GTV. The mean volume of the anal sphincter was 16.1 +/- 3.5 cm(3). The dose distributed to the GTV in the real plan and in the virtual simulated block plan were 51.7 +/- 1.4 and 51.6 +/- 1.4 Gy respectively (P = 0.85). By comparison the mean dose distributed to the anal sphincter was dramatically reduced by using a sphincter block (33.2 +/- 12 Gy vs 6.4 +/- 4.1 Gy, P < 0.001).

CONCLUSION

During a course of radiotherapy for most low- or mid-rectal cancers, the anal canal is included within the field of irradiation with a mean dose distribution to the sphincter of 33 Gy. Evaluation of 3DXRT with full sphincter block (mid-rectum) and partial sphincter block (distal rectum) is a feasible strategy to decrease the volume of anal sphincter carried to full dose without reduction in dose to the GTV. This approach, by minimizing treatment-induced damage to the anal sphincter, might improve functional outcome of LAR.

Intergroup RTOG 98–11: A phase III randomized study of 5-fluorouracil (5-FU), mitomycin, and radiotherapy versus 5-fluorouracil, cisplatin and radiotherapy in carcinoma of the anal canal

4009

Background: An ∼65% 5-year disease-free-survival (DFS) rate from 5-FU/mitomycin/radiation for anal carcinoma needs improvement. Methods: A phase III randomized trial compared 5-FU (1,000mg/m2 days 1–4 and 29–32) plus mitomycin (10mg/m2 days 1 and 29) and radiation (45 to 59 Gy) (Arm A) to 5-FU (1,000mg/m2 days 1–4, 29–32, 57–60 and 85–88) plus cisplatin (75mg/m2 on days 1, 29, 57 and 85) and radiation (45 to 59 Gy; start day=57) (Arm B) in anal carcinoma patients. Stratification included gender, clinical N status and tumor diameter. Primary endpoint was DFS. Statistical power was 80% with two-sided test to detect 10% DFS increase for Arm B. Results: Of 682 patients accrued, 598 were analyzable. Most unanalyzed patients’ data are early. Patient characteristics were balanced. Median age was 55 years, women predominated (69%), 27.5% had >5 cm tumor diameter and 26% had clinically N+ cancer. Preliminary 5-year estimated DFS was 56% for Arm A and 48% for Arm B (p=0.28) and 5-year estimated overall survival was 69% for both arms (p=0.24). Men(p=0.04), clinically N+ cancer (p<0.0001) and tumor diameter >5 cm (p=0.005) independently prognosticated DFS in a multivariate analysis. 5-year colostomy rate was 10% for Arm A and 20% for arm B(p=0.12). Grade 3/4 toxicity rates: non-hematologic=76% for Arm A and 75% for Arm B but hematologic=67% for Arm A and 47% for Arm B(p=0.0004). Conclusions: In Intergroup-98–11, induction 5-FU/cisplatin followed by 5-FU/cisplatin/radiation failed to improve DFS compared to the standard treatment, 5-FU/mitomycin/radiation. Supported by RTOG U10 CA21661, CCOP U10 CA37422, Stat U10 CA32115.

No significant financial relationships to disclose.

Multi-institutional trial of preoperative chemoradiotherapy in patients with potentially resectable gastric carcinoma

PURPOSE

In the West, curative (R0) resection is achieved in approximately 50% of patients with localized gastric carcinoma, and more than 60% die of cancer following an R0 resection. A multi-institutional study of preoperative chemoradiotherapy was done to assess the R0 resection rate, pathologic complete response (pathCR) rate, safety, and survival in patients with resectable gastric carcinoma.

PATIENTS AND METHODS

Operable patients with localized gastric adenocarcinoma were eligible. Staging also included a laparoscopy and endoscopic ultrasonography (EUS). Patients received up to two 28-day cycles of induction chemotherapy of fluorouracil, leucovorin, and cisplatin, followed by 45 Gy of radiation plus concurrent fluorouracil. Patients were then staged and surgery was attempted.

RESULTS

Thirty-four patients were registered at three institutions. One ineligible patient was excluded. Most patients had a promixal cancer and EUST3N1 designation. Twenty-eight (85%) of 33 patients underwent surgery. The R0 resection rate was 70% and pathCR rate was 30%. A pathologic partial response (< 10% residual carcinoma in the primary) occurred in eight patients (24%). EUS T plus N and postsurgery T plus N correlation showed significant downstaging (P = <.01). The median survival time for 33 patients was 33.7 months. Patients achieving a pathCR or pathPR had a significantly longer median survival time (63.9 months) than those achieving less than pathPR (12.6 months; P =.03). There were two treatment-related deaths.

CONCLUSION

Our data suggest that the three-step strategy of preoperative induction chemotherapy followed by chemoradiotherapy resulted in substantial pathologic response that resulted in durable survival time. This strategy is worthy of a direct comparison with postoperative adjuvant chemoradiotherapy.

Multi-institutional trial of preoperative chemoradiotherapy in patients with potentially resectable gastric carcinoma

PURPOSE

In the West, curative (R0) resection is achieved in approximately 50% of patients with localized gastric carcinoma, and more than 60% die of cancer following an R0 resection. A multi-institutional study of preoperative chemoradiotherapy was done to assess the R0 resection rate, pathologic complete response (pathCR) rate, safety, and survival in patients with resectable gastric carcinoma.

PATIENTS AND METHODS

Operable patients with localized gastric adenocarcinoma were eligible. Staging also included a laparoscopy and endoscopic ultrasonography (EUS). Patients received up to two 28-day cycles of induction chemotherapy of fluorouracil, leucovorin, and cisplatin, followed by 45 Gy of radiation plus concurrent fluorouracil. Patients were then staged and surgery was attempted.

RESULTS

Thirty-four patients were registered at three institutions. One ineligible patient was excluded. Most patients had a promixal cancer and EUST3N1 designation. Twenty-eight (85%) of 33 patients underwent surgery. The R0 resection rate was 70% and pathCR rate was 30%. A pathologic partial response (< 10% residual carcinoma in the primary) occurred in eight patients (24%). EUS T plus N and postsurgery T plus N correlation showed significant downstaging (P = <.01). The median survival time for 33 patients was 33.7 months. Patients achieving a pathCR or pathPR had a significantly longer median survival time (63.9 months) than those achieving less than pathPR (12.6 months; P =.03). There were two treatment-related deaths.

CONCLUSION

Our data suggest that the three-step strategy of preoperative induction chemotherapy followed by chemoradiotherapy resulted in substantial pathologic response that resulted in durable survival time. This strategy is worthy of a direct comparison with postoperative adjuvant chemoradiotherapy.

Adjuvant therapy in rectal cancer: analysis of stage, sex, and local control--final report of intergroup 0114

PURPOSE

The gastrointestinal Intergroup studied postoperative adjuvant chemotherapy and radiation therapy in patients with T3/4 and N+ rectal cancer after potentially curative surgery to try to improve chemotherapy and to determine the risk of systemic and local failure.

PATIENTS AND METHODS

All patients had a potentially curative surgical resection and were treated with two cycles of chemotherapy followed by chemoradiation therapy and two additional cycles of chemotherapy. Chemotherapy regimens were bolus fluorouracil (5-FU), 5-FU and leucovorin, 5-FU and levamisole, and 5-FU, leucovorin, and levamisole. Pelvic irradiation was given to a dose of 45 Gy to the whole pelvis and a boost to 50.4 to 54 Gy.

RESULTS

One thousand six hundred ninety-five patients were entered and fully assessable, with a median follow-up of 7.4 years. There was no difference in overall survival (OS) or disease-free survival (DFS) by drug regimen. DFS and OS decreased between years 5 and 7 (from 54% to 50% and 64% to 56%, respectively), although recurrence-free rates had only a small decrease. The local recurrence rate was 14% (9% in low-risk [T1 to N2+] and 18% in high-risk patients [T3N+, T4N]). Overall, 7-year survival rates were 70% and 45% for the low-risk and high-risk groups, respectively. Males had a poorer overall survival rate than females.

CONCLUSION

There is no advantage to leucovorin- or levamisole-containing regimens over bolus 5-FU alone in the adjuvant treatment of rectal cancer when combined with irradiation. Local and distant recurrence rates are still high, especially in T3N+ and T4 patients, even with full adjuvant chemoradiation therapy.

Chemoradiotherapy after surgery compared with surgery alone for adenocarcinoma of the stomach or gastroesophageal junction

BACKGROUND

Surgical resection of adenocarcinoma of the stomach is curative in less than 40 percent of cases. We investigated the effect of surgery plus postoperative (adjuvant) chemoradiotherapy on the survival of patients with resectable adenocarcinoma of the stomach or gastroesophageal junction.

METHODS

A total of 556 patients with resected adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to surgery plus postoperative chemoradiotherapy or surgery alone. The adjuvant treatment consisted of 425 mg of fluorouracil per square meter of body-surface area per day, plus 20 mg of leucovorin per square meter per day, for five days, followed by 4500 cGy of radiation at 180 cGy per day, given five days per week for five weeks, with modified doses of fluorouracil and leucovorin on the first four and the last three days of radiotherapy. One month after the completion of radiotherapy, two five-day cycles of fluorouracil (425 mg per square meter per day) plus leucovorin (20 mg per square meter per day) were given one month apart.

RESULTS

The median overall survival in the surgery-only group was 27 months, as compared with 36 months in the chemoradiotherapy group; the hazard ratio for death was 1.35 (95 percent confidence interval, 1.09 to 1.66; P=0.005). The hazard ratio for relapse was 1.52 (95 percent confidence interval, 1.23 to 1.86; P<0.001). Three patients (1 percent) died from toxic effects of the chemoradiotherapy; grade 3 toxic effects occurred in 41 percent of the patients in the chemoradiotherapy group, and grade 4 toxic effects occurred in 32 percent.

CONCLUSIONS

Postoperative chemoradiotherapy should be considered for all patients at high risk for recurrence of adenocarcinoma of the stomach or gastroesophageal junction who have undergone curative resection.

Intraoperative irradiation for locally recurrent colorectal cancer in previously irradiated patients

PURPOSE

Information in the literature regarding salvage treatment for patients with locally recurrent colorectal cancer who have previously been treated with high or moderate dose external beam irradiation (EBRT) is scarce. A retrospective review was therefore performed in our institution to determine disease control, survival, and tolerance in patients treated aggressively with surgical resection and intraoperative electron irradiation (IOERT) +/- additional EBRT and chemotherapy.

METHODS AND MATERIALS

From 1981 through 1994, 51 previously irradiated patients with recurrent locally advanced colorectal cancer without evidence of distant metastatic disease were treated at Mayo Clinic Rochester with surgical resection and IOERT +/- additional EBRT. An attempt was made to achieve a gross total resection before IOERT if it could be safely accomplished. The median IOERT dose was 20 Gy (range, 10--30 Gy). Thirty-seven patients received additional EBRT either pre- or postoperatively with doses ranging from 5 to 50.4 Gy (median 25.2 Gy). Twenty patients received 5-fluorouracil +/- leucovorin during EBRT. Three patients received additional cycles of 5-fluorouracil +/- leucovorin as maintenance chemotherapy.

RESULTS

Thirty males and 21 females with a median age of 55 years (range 31--73 years) were treated. Thirty-four patients have died; the median follow-up in surviving patients is 21 months. The median, 2-yr, and 5-yr actuarial overall survivals are 23 months, 48% and 12%, respectively. The 2-yr actuarial central control (within IOERT field) is 72%. Local control at 2 years has been maintained in 60% of patients. There is a trend toward improved local control in patients who received > or =30 Gy EBRT in addition to IOERT as compared to those who received no EBRT or <30 Gy with 2-yr local control rates of 81% vs. 54%. Distant metastatic disease has developed in 25 patients, and the actuarial rate of distant progression at 2 and 4 years is 56% and 76%, respectively. Peripheral neuropathy was the main IOERT-related toxicity; 16 (32%) patients developed neuropathies (7 mild, 5 moderate, 4 severe). Ureteral narrowing or obstruction occurred in seven patients. All but one patient with neuropathy or ureter fibrosis received IOERT doses > or =20 Gy.

CONCLUSION

Long-term local control can be obtained in a substantial proportion of patients with aggressive combined modality therapy, but long-term survival is poor due to the high rate of distant metastasis. Re-irradiation with EBRT in addition to IOERT appears to improve local control. Strategies to improve survival in these poor-risk patients may include the more routine use of conventional systemic chemotherapy or the addition of novel systemic therapies.

Treatment of cholangiocarcinoma complicating primary sclerosing cholangitis: the Mayo Clinic experience

OBJECTIVES

The aims of this retrospective study were to assess the frequency with which we used different treatment modalities for patients with primary sclerosing cholangitis (PSC) and cholangiocellular carcinoma (CCA).

METHODS

A total of 41 patients with known CCA complicating PSC with a median age of 49 yr (range, 27-75 yr) were identified from a group of 1009 patients (4%) with PSC seen over 10 yr at the Mayo Clinic.

RESULTS

These patients received mainly five forms of treatment: 10 patients were treated with radiation therapy (RT) with or without 5-fluorouracil (5-FU) (seven with palliative and three with curative intent), nine with stent placement for cholestasis, 12 with conservative treatment, four with surgical resection (one of four received RT and 5-FU), and three patients with orthotopic liver transplantation and RT, with or without 5-FU. One patient was treated with 5-FU alone, one with photodynamic therapy, and one patient with somatostatin analog. A total of 36 patients died, whereas four (10%) patients survived (two with surgical resection, one with orthotopic liver transplantation and RT, and one with stent placement) during a median follow-up of 5.5 months (range, 1-75 months). One patient was lost to follow-up.

CONCLUSIONS

In highly selective cases, resective surgery seems to be of benefit in PSC patients with CCA. However, these therapies are rarely applied to these patients because of the advanced nature of the disease at the time of diagnosis. Efforts should be directed at earlier identification of potential surgical candidates.

Prolonged disease-free survival after orthotopic liver transplantation plus adjuvant chemoirradiation for cholangiocarcinoma

Orthotopic liver transplantation (OLT) alone for unresectable cholangiocarcinoma is often associated with early disease relapse and limited survival. Because of these discouraging results, most programs have abandoned OLT for cholangiocarcinoma. However, a small percentage of patients have achieved prolonged survival after OLT, suggesting that adjuvant approaches could perhaps improve the survival outcome. Based on these concepts, a protocol was developed at the Mayo Clinic using preoperative irradiation and chemotherapy for patients with cholangiocarcinoma. We report our initial results with this pilot experience. Patients with unresectable cholangiocarcinoma above the cystic duct without intrahepatic or extrahepatic metastases were eligible. Patients initially received external-beam irradiation plus bolus fluorouracil (5-FU), followed by brachytherapy with iridium and concomitant protracted venous infusion of 5-FU. 5-FU was then administered continuously through an ambulatory infusion pump until OLT. After irradiation, patients underwent an exploratory laparotomy to exclude metastatic disease. To date, 19 patients have been enrolled onto the study and have been treated with irradiation. Eight patients did not go on to OLT because of the presence of metastasis at the time of exploratory laparotomy (n = 6), subsequent development of malignant ascites (n = 1), or death from intrahepatic biliary sepsis (n = 1). Eleven patients completed the protocol with successful OLT. Except for 1 patient, all had early-stage disease (stages I and II) in the explanted liver. All patients who underwent OLT are alive, 3 patients are at risk at 12 months or less, and the remaining 8 patients have a median follow-up of 44 months (range, 17 to 83 months; 7 of 9 patients > 36 months). Only 1 patient developed tumor relapse. OLT in combination with preoperative irradiation and chemotherapy is associated with prolonged disease-free and overall survival in highly selected patients with early-stage cholangiocarcinoma.

Sacropelvic resection for recurrent anorectal cancer. A multidisciplinary approach

A multimodal approach including preoperative external beam radiation, surgical resection, and intraoperative electron radiation was used in 23 patients with locally advanced anal or recurrent rectal cancers involving the sacrum. The proximal extent of complete sacral resection was S2 in three patients, S3 in 12 patients, S4 in two patients, and S5 in one patient. The tumor was confined to the anterior sacral cortex in five patients. The resection was marginal in 10, contaminated marginal in 11, and intralesional in two patients. At 19 to 54 months of followup, five patients are alive without evidence of disease and four are alive with disease. Twelve patients died of their disease, and two died of other causes. There was a mean survival of 32.9 months for the patients who were alive at followup. Kaplan-Meier survival for all patients was 82% at 1 year and 73% at 2 years, with death of disease as an endpoint. Thirteen (57%) patients had another local recurrence develop at a mean of 17.2 months. Eight (35%) patients had metastatic disease develop at a mean of 16.3 months. Proper patients selection is important in ensuring a favorable outcome from this aggressive surgery.

Results of irradiation or chemoirradiation following resection of gastric adenocarcinoma

PURPOSE

To evaluate the results of postoperative irradiation +/- chemotherapy for carcinoma of the stomach and gastroesophageal junction.

METHODS AND MATERIALS

The records of 63 patients who underwent resection for stomach cancer were retrospectively reviewed. Twenty-five patients had complete resection with no residual disease but with high-risk factors for relapse. Twenty-eight had microscopic residual and 10 had gross residual disease. Doses of irradiation ranged from 39.6 to 59.4 Gy with a median dose of 50.4 Gy in 1.8 Gy fractions. Fifty-three of the 63 (84%) patients received 5-fluorouracil (5-FU)-based chemotherapy.

RESULTS

The median duration of survival was 19.3 months for patients with no residual disease, 16.7 months for those with microscopic residual disease, and 9.2 months for those with gross residual disease (p = 0.01). The amount of residual disease also significantly impacted locoregional control (p = 0.04). Patients with linitis plastica did significantly worse in terms of survival, locoregional control, and distant control than those without linitis plastica. The use of 4 or more irradiation fields was associated with a significant decrease in the rate of Grade 4 or 5 toxicity when compared to the patients treated with 2 fields (p = 0.05).

CONCLUSIONS

There was a significant association between survival and extent of residual disease after resection as well as the presence of linitis plastica. Distant failures are common and effective systemic therapy will be necessary to improve outcome. The toxicity of combined modality treatment appears to be reduced by using greater than 2 irradiation fields.

Outcomes of patients receiving radiation for carcinoma of the rectum. Results of the 1988-1989 patterns of care study

BACKGROUND

Clinical trials of surgical adjuvant treatment for patients with rectal carcinoma (RC) indicate that postoperative radiation therapy with concurrent chemotherapy (CRT) is superior to postoperative radiation alone (RT) or surgery alone. Whether preoperative treatment is superior to postoperative treatment is controversial. This Patterns of Care Study (PCS) surveyed patients with RC treated with radiation during the years 1988-1989 to determine the national practice standards and outcomes and to compare these results with those of clinical trials.

METHODS

A national survey of 73 institutions was conducted using 2-stage cluster sampling, and specific information on 406 patients with RC who received radiation at 69 facilities was collected. Follow-up information on 215 patients was subsequently collected by mail survey. There were no significant differences between the known prognostic indicators or treatment-related variables for patients for whom follow-up was available compared with the variables for patients for whom follow-up was not available. Follow-up ranged from 0 to 8.44 years with a median of 4 years. One hundred fifty-four patients (71%) received postoperative treatment, either RT (37%) or CRT (34%); and 40 (18%) received preoperative treatment, either RT (15%) or CRT (3%). Ninety-six patients (45%) received chemotherapy, and for 86% of those patients chemotherapy was administered concurrently with radiation.

RESULTS

Survival was stage-dependent (85% Stage I, 69% Stage II, and 54% Stage III at 5 years, P = 0.04). Survival was also substage-dependent, and patients with C(1) cancer had significantly higher 5-year survival than those with C(2)/C(3) cancer (89% vs. 48%, P = 0.008). Local failure was similar for Stage II and Stage III patients (10% vs. 11% at 5 years, respectively). In multivariate analyses, only stage and use of chemotherapy were significant to survival (Stage III vs. Stage I and II, relative risk [RR] = 2.52, and chemotherapy vs. no chemotherapy, RR = 0.46). A significantly higher 5-year survival rate was seen with postoperative CRT than with postoperative RT (69% vs. 50%, P = 0. 011). Preoperative radiation resulted in a significantly higher 5-year survival rate than postoperative radiation (85% vs. 50%, P = 0.0006), but not compared with postoperative CRT. Survival and local failure did not differ according to radiation therapy interruption or the interval between surgery and radiation.

CONCLUSIONS

Stage is an important prognostic indicator for survival, and among patients with Stage III malignancies survival in the substage C(1) is significantly higher than in the substages C(2) and C(3). As has been demonstrated in randomized trials, adjuvant postoperative CRT is superior to postoperative RT for patients with RC in this national study. These nationwide results of adjuvant treatment are comparable to those reported in randomized trials. The use of CRT was the only treatment-related factor that resulted in a significant reduction in the risk of death.

Results of irradiation or chemoirradiation for primary unresectable, locally recurrent, or grossly incomplete resection of gastric adenocarcinoma

OBJECTIVE

To evaluate the results of irradiation +/- chemotherapy for patients with unresectable gastric carcinoma.

MATERIALS AND METHODS

The records of 60 patients with a gastric or gastroesophageal junction adenocarcinoma and a locally advanced unresectable primary (n = 28), a local or regional recurrence (n = 21), or gross residual disease following incomplete resection (n = 11) were retrospectively reviewed. Patients were treated with external beam irradiation (EBRT) alone or external beam plus intraoperative irradiation (IOERT), and 55 of the 60 (92%) patients received 5-FU based chemotherapy.

RESULTS

The median survival for the entire cohort was 11.6 months. There was no significant difference in median survival between each of the three treatment groups. In examining the extent of disease there was a significant difference in survival based on the number of sites involved. Nine patients with disease limited to a single non-nodal site appeared to represent a favorable subgroup compared to the rest of the patients (median survival of 21.8 months vs. 10.2 months,p = 0.03). In the patients with recurrent disease, the number of sites involved (p = 0.05), and total dose adding external beam dose to IOERT dose (> 54 Gy vs. < or =54 Gy, p = 0.06) were of borderline significance in regard to survival.

CONCLUSIONS

In patients with either primary unresectable, locally or regionally recurrent, or incompletely resected gastric carcinoma, the overall survival is similar, and related to the extent of disease based on the number of regional sites involved. The patients with a single non-nodal site of disease represent a favorable subgroup and patients with recurrent disease may benefit from total irradiation doses > 54 Gy.

Outcomes of patients receiving radiation for carcinoma of the rectum. Results of the 1988-1989 patterns of care study

BACKGROUND

Clinical trials of surgical adjuvant treatment for patients with rectal carcinoma (RC) indicate that postoperative radiation therapy with concurrent chemotherapy (CRT) is superior to postoperative radiation alone (RT) or surgery alone. Whether preoperative treatment is superior to postoperative treatment is controversial. This Patterns of Care Study (PCS) surveyed patients with RC treated with radiation during the years 1988-1989 to determine the national practice standards and outcomes and to compare these results with those of clinical trials.

METHODS

A national survey of 73 institutions was conducted using 2-stage cluster sampling, and specific information on 406 patients with RC who received radiation at 69 facilities was collected. Follow-up information on 215 patients was subsequently collected by mail survey. There were no significant differences between the known prognostic indicators or treatment-related variables for patients for whom follow-up was available compared with the variables for patients for whom follow-up was not available. Follow-up ranged from 0 to 8.44 years with a median of 4 years. One hundred fifty-four patients (71%) received postoperative treatment, either RT (37%) or CRT (34%); and 40 (18%) received preoperative treatment, either RT (15%) or CRT (3%). Ninety-six patients (45%) received chemotherapy, and for 86% of those patients chemotherapy was administered concurrently with radiation.

RESULTS

Survival was stage-dependent (85% Stage I, 69% Stage II, and 54% Stage III at 5 years, P = 0.04). Survival was also substage-dependent, and patients with C(1) cancer had significantly higher 5-year survival than those with C(2)/C(3) cancer (89% vs. 48%, P = 0.008). Local failure was similar for Stage II and Stage III patients (10% vs. 11% at 5 years, respectively). In multivariate analyses, only stage and use of chemotherapy were significant to survival (Stage III vs. Stage I and II, relative risk [RR] = 2.52, and chemotherapy vs. no chemotherapy, RR = 0.46). A significantly higher 5-year survival rate was seen with postoperative CRT than with postoperative RT (69% vs. 50%, P = 0. 011). Preoperative radiation resulted in a significantly higher 5-year survival rate than postoperative radiation (85% vs. 50%, P = 0.0006), but not compared with postoperative CRT. Survival and local failure did not differ according to radiation therapy interruption or the interval between surgery and radiation.

CONCLUSIONS

Stage is an important prognostic indicator for survival, and among patients with Stage III malignancies survival in the substage C(1) is significantly higher than in the substages C(2) and C(3). As has been demonstrated in randomized trials, adjuvant postoperative CRT is superior to postoperative RT for patients with RC in this national study. These nationwide results of adjuvant treatment are comparable to those reported in randomized trials. The use of CRT was the only treatment-related factor that resulted in a significant reduction in the risk of death.

Conformal irradiation for hepatobiliary malignancies

The term 'conformal irradiation' is usually used to describe the delivery of sophisticated high dose external beam irradiation (EBRT) with the aid of 3-D treatment planning and the option of both coplanar and non-coplanar beams. Data will be presented from the University of Michigan which suggest that conformal high dose EBRT (48-72.6 Gy) can be used for intrahepatic cancers, both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (IHCC), to potentially increase local control and survival over what would be expected with lower dose EBRT. For purpose of this discussion, the term conformal irradiation will be expanded to include other techniques which conform the high dose irradiation boost volume in close proximity to unresected tumor or positive margins of resection. Data will be presented from series which utilize transcatheter iridium and intraoperative electron irradiation (IOERT) supplements to EBRT +/- concomitant chemotherapy. Each method intensifies treatment in an attempt to improve local control and survival.

Future role of radiotherapy as a component of treatment in biliopancreatic cancers

For resected and unresectable pancreas cancers, data will be summarized from both adjuvant and locally unresectable pancreas cancer series (EBRT +/- IOERT) to demonstrate the justification of continuing to utilize chemo-irradiation as a component of treatment. The resultant improvements in local control with combined modality treatment, however, achieve only minimal improvements in survival in view of the high incidence of abdominal relapse (liver and peritoneal). Further improvement in survival may necessitate regional approaches for chemotherapy or may await advances in gene therapy. For locally unresectable and resected but residual bile duct malignancies, chemoirradiation appears to enhance tumor control and survival. Dose intensification of both modalities may be useful in improving disease control and survival. After chemoirradiation, the addition of liver transplant, in carefully selected patients who are unresectable with standard resection, may further enhance disease control and survival over what would be expected with either approach in isolation.

Energy and applicator size and shape used in over 800 intraoperative electron beam therapy fields

Intraoperative radiotherapy is a treatment option for some patients with locally advanced malignancies. This report updates the Mayo Clinic experience in more than 800 patients by analyzing the use of electron energy and cone size and shape by disease site between 1981 and 1996.

Indications for and results of combined modality treatment of colorectal cancer

Combined modality chemoirradiation is commonly used as a component of treatment in combination with maximum resection for both high-risk resectable and locally advanced primary or recurrent rectal cancers. With surgically resected but high-risk rectal cancers, postoperative chemoirradiation has been shown to improve both disease control (local and distant) and survival (disease-free and overall) and was recommended as standard adjuvant treatment at the 1990 National Institute of Health (NIH) Consensus Conference on Adjuvant treatment for patients with rectal and colon cancers. Subsequent intergroup trials are being conducted to help define optimal combinations of postoperative chemoirradiation for resected high-risk rectal cancers and to test sequencing issues of preoperative versus postoperative chemoirradiation. With locally unresectable primary or recurrent colorectal cancers, standard therapy with surgery, external beam irradiation (EBRT) and chemotherapy is often unsuccessful. When intraoperative electron irradiation (IOERT) is combined with standard treatment, local control and survival appear to be improved in separate analyses from the Mayo Clinic and the Massachusetts General Hospital (MGH). However, routine use of systemic therapy is also needed as a component of treatment, in view of high rates of systemic failure.

The incidence and clinical consequences of treatment-related bowel injury

OBJECTIVE

To assess the frequency and clinical features of treatment-induced bowel injury in rectal carcinoma patients receiving perioperative external beam radiotherapy (EBRT). The frequency of and factors associated with treatment-induced intestinal injury have previously not been well quantified for rectal cancer patients. Postoperative adjuvant chemoirradiation is recommended for Stage II and III rectal cancers, making such data of significant interest.

METHODS AND MATERIALS

The records of 386 consecutive patients undergoing radiotherapy with or without chemotherapy (CT) for rectal carcinoma between 1981-90 were reviewed. Eight-two patients were excluded for receiving nontherapeutic EBRT or modalities other than EBRT.

RESULTS

Symptomatic acute treatment-related enteritis (within 30 days of EBRT +/- CT) was diagnosed in 13 patients, 3 of whom developed chronic bowel injury. Chronic treatment-related enteritis was identified in 18 patients and reoperation was required in 17 (5% of the 304 patients with complete follow-up). Chronic proctitis was documented in 38 patients, including 3 patients with small bowel injury. The probability of developing treatment-induced bowel injury at 5 years following treatment was 19%. Variables associated with an increased risk of bowel injury using multivariate analysis were transanal excision (p = 0.002), escalating radiation dose (p = 0.005), and increasing age (p = 0.01). Twenty of the affected patients required operative treatment, and 2 deaths resulted from treatment-induced enteritis.

CONCLUSION

Patients with rectal carcinoma treated with EBRT +/- CT have the risk of developing treatment-induced bowel injury. The pelvic radiation dose should be limited to < or = 5040 cGy unless small bowel can be displaced. Reperitonealization of the pelvis, or other surgical methods of excluding the small intestine should be used whenever possible.

Malignant peripheral nerve sheath tumor: analysis of treatment outcome

PURPOSE

To analyze the results of therapy for malignant peripheral nerve sheath tumor (MPNST) and to identify prognostic factors of survival, and of local and distant control of disease.

METHODS AND MATERIALS

From 1975 through 1993, 134 MPNSTs were diagnosed and treated at our institution. Tumor sites included extremities in 36 (27%) cases and non-extremities in 98 (73%). Median follow-up for survivors was 53 months (range: 7-280). There were 14 tumors of histologic grade I disease (10%), 43 of grade II disease (32%), 43 of grade III disease (32%), and 32 of grade IV (24%). Seventy-three patients (54%) underwent radiation therapy (RT) as part of their initial treatment of the primary tumor, including 14 (10%) who had brachytherapy and 16 (12%) who had intraoperative electron irradiation (IOERT) as part of their radiation course.

RESULTS

The 5- and 10-year survival rates were 52% and 34%, respectively. Local and distant failure rates at 5 years were both 49%. On univariate analysis, prognostic factors significantly related to survival (log-rank: p < 0.05) included tumor size, location of disease, history of neurofibromatosis type 1 (NF-1), history of prior irradiation, surgical margin status, use of IOERT or brachytherapy, disease stage, histologic grade and tumor subtype, as well as mitotic rate and the presence or absence of necrosis. On multivariate analysis, only history of prior irradiation (p = 0.023), and surgical margin status (p = 0.0044) remained significant. For local control of disease, univariate analysis showed location of disease, surgical margin status, history of NF-1, history of prior irradiation, mitotic rate, radiation dose > or = 60 Gy, and use of IOERT or brachytherapy to be significant prognostic factors. On multivariate analysis, only surgical margin status (p = 0.0024), RT dose (p = 0.021), and use of IOERT or brachytherapy (p = 0.016) remained significant. For distant control of disease, significant prognostic factors on univariate analysis included tumor size, stage, tumor grade, mitotic rate, presence or absence of necrosis, and histologic subtype. On multivariate analysis, tumor size (p = 0.0065), grade (p = 0.036), and histologic subtype (p = 0.001) remained significant. Patients with perineurial MPNSTs had a much lower rate of distant metastasis and a better overall survival as compared with other histologic subtypes.

CONCLUSION

Management of patients with MPNST involves a multi-modality approach. The goal of surgery is complete resection with negative margins. Adjuvant irradiation to doses > or = 60 Gy and the inclusion of IOERT or brachytherapy are associated with improved local control of disease.

Adjuvant postoperative radiation therapy +/- 5-FU in resected carcinoma of the pancreas

Ductal adenocarcinoma of the pancreas was the fourth leading cause of cancer related deaths in the United States in 1996. Pancreatic cancer is often considered a uniformly fatal disease due to its usually advanced stage at presentation. Only 5-25% of cases are resectable and surgery offers the only single modality hope of potential cure. In the past, even resectable tumors were considered incurable. Retrospective analyses of patterns of failure and prognostic variables following surgical resection, however, have resulted in randomized and non-randomized trials that have succeeded in doubling the median and long-term survival with the use of adjuvant postoperative chemoradiation. Subsequent analyzes of failure patterns following adjuvant treatment in patients with resected pancreas cancer have shown an improvement in local control, but the majority of patients continue to develop either liver and/or peritoneal metastases. To further improve survival in surgically resectable carcinoma of the pancreas, better systemic treatment and/or abdominal prophylaxis needs to be evaluated in controlled clinical trials.

Intraoperative irradiation: current and future status

Intraoperative radiation therapy (IORT) in its broadest sense refers to the delivery of irradiation at the time of an operation. This article will discusses the rationale for and results of both intraoperative electron radiation therapy and intraoperative high dose rate brachytherapy when used in conjunction with surgical exploration and resection and external beam radiation therapy and chemotherapy. Both IORT methods evolved with similar philosophies as an attempt to achieve higher effective doses of irradiation while dose limiting structures are surgically displaced.

External radiation therapy and transcatheter iridium in the treatment of extrahepatic bile duct carcinoma

PURPOSE/OBJECTIVE

Review survival, prognostic factors, and patterns of failure in patients with extrahepatic bile duct (EHBD) carcinoma treated with external beam irradiation (EBRT) and transcatheter iridium.

METHODS AND MATERIALS

The charts of 24 patients with EHBD cancer treated with EBRT and transcatheter boost were reviewed. All patients had transhepatic biliary tubes or endoprostheses placed. Two patients underwent hemihepatectomy with hepaticojejunostomy formation but had residual disease. Two patients had biopsy proven adenopathy. Five patients had Grade 1 adenocarcinoma, nine Grade 2, six Grade 3, and one Grade 4 disease. Median EBRT dose was 50.4 Gy delivered in 1.8 Gy/day fractions. Median transcatheter boost at 1 cm radius was 20 Gy. Nine patients received concomitant 5-Fluorouracil (5-FU) during EBRT.

RESULTS

Median survival was 12.8 months (range 7.5 months to 9 years). Overall 2- and 5-year survival rates were 18.8 and 14.1%, respectively (three disease-free survivors > or =5 years). One patient is still alive without relapse 10 years from diagnosis and 5 years after liver transplantation for liver failure (no cancer in specimen, underlying sclerosing cholangitis). Two additional long-term survivors had no evidence of relapse 6.9 and 8.2 years after diagnosis. Histologic grade, lymph node status, cystic, hepatic, common hepatic or common bile duct involvement, surgical resection, radiation therapy dose, and chemotherapy did not significantly effect survival due to the number of patients analyzed. There was a trend towards improved survival with the addition of 5-FU chemotherapy (5-year survival in two of nine patients, or 22%). Eight of 24 patients (33%) demonstrated radiographic evidence of local recurrence. Distant metastases developed in 6 of 24 (25%) patients. The most common complications were tube related cholangitis (50%) and gastric/duodenal ulceration or bleeding (42%).

CONCLUSION

External beam irradiation combined with a transcatheter boost can result in long-term survival of patients with EHBD cancer. Both distant metastases and local recurrence develop in 25-30% of patients despite irradiation. Survival may be improved by using chemotherapy in combination with EBRT to impact disease relapse (local and distant). Because there may be a dose response with irradiation, survival may also be improved by increasing the dose of radiation delivered by transcatheter boost. A Phase II trial is being developed using a combination of 45-50 Gy EBRT with concomitant 5-FU delivered by protracted venous infusion followed by a 25-30 Gy transcatheter boost.

Use of brachytherapy in management of locally recurrent rectal cancer

PURPOSE

Locally recurrent rectal cancer is associated with poor quality of life and has justified aggressive surgical and adjuvant approaches to control the disease. This study was designed to evaluate if the use of brachytherapy in association with wide surgical excision (debulking operation) can offer reasonable palliation for patients with locally recurrent rectal cancer.

MATERIALS AND METHODS

Patients with biopsy-proven locally recurrent rectal cancer who were not candidates for intraoperative radiation therapy and who were previously considered as having unresectable tumors were included in the study and were followed-up from May 1981 to November 1990. All of them had undergone laparotomy and had either radical or debulking surgical resection performed. At the same time, brachytherapy was used with temporary or permanent implant of seeds of iridium-192 or iodine-125.

RESULTS

Thirty patients were included. Patients ranged in age from 28 to 74 years, and 16 patients were female. No mortality was observed, and morbidity was low (small-bowel obstruction (1 patient), intestinal fistula (1 patient), and urinary fistula (1 patient). Histologic examination of the specimen showed gross residual disease in 67 percent of patients and microscopic disease in 25 percent of patients. Long-term follow-up was possible in 28 patients. Mean follow-up and local control were, respectively, 26.5 months and 37.5 percent for gross residual disease and 34 months and 66 percent for microscopic residual disease. Eighteen patients (64 percent) had locally recurrent rectal cancer under control at the time of the last follow-up, with seven patients (25 percent) having no evidence of local or distant recurrence.

CONCLUSION

This is the first report of brachytherapy for locally recurrent rectal cancer. This appears to offer a therapeutic alternative to patients who are not candidates for intraoperative radiation therapy. Surgical morbidity and mortality are acceptable. Local control in 18 patients (64 percent) is comparable with intraoperative radiation therapy or more morbid surgical alternatives. Cancer-related deaths are most often related to disseminated disease, which suggests the need for systemic therapy in addition to brachytherapy.

Postoperative localization of porta hepatis and abdominal vasculature in pancreatic malignancies: implications for postoperative radiotherapy planning

PURPOSE

To evaluate changes in preoperative and postoperative positions of structures used to define target volumes (i.e., pancreatic bed, porta hepatis, local-regional lymph nodes) for postoperative irradiation of pancreatic malignancies as defined by abdominal computed tomographs.

METHODS AND MATERIALS

Eleven consecutive patients who had Whipple resection and postoperative irradiation for pancreatic cancer were evaluated. Preoperative and postoperative computed tomographs of each patient were evaluated for the position of the portal vein bifurcation and the origin of the celiac axis and superior mesenteric artery. The length along the x (medial-lateral position) and y (anterior-posterior position) axes was determined with calipers to the closest millimeter. Length along the z axis (cephalad-caudad position) was determined with the computed tomographic sectional interval between images. Statistical significance of the change in the structure's position along the x, y, or z axis between preoperative and postoperative computed tomographs was assessed with the paired t-test.

RESULTS

Evaluation of the preoperative and postoperative positions of the portal vein, celiac axis, and superior mesenteric artery along the x, y, and z axes revealed a statistically significant change in the location of the portal vein and celiac axis postoperatively. The median change of the celiac axis in the anterior-posterior position was significant (p = 0.0047), but the mean change was only 2 mm and not considered clinically significant. The median change for the portal vein was 0.97 cm and 1.07 cm along the y and x axes, respectively, and was significant (p = 0.008 and p = 0.0001). The range in position change for the portal vein was 0.0 to 2.0 cm along the y axis and 0.4 to 1.9 along the x axis. The remaining mean changes in position along all axes for all the structures were less than 3 mm (not statistically significant).

CONCLUSIONS

The mean position of the portal vein-porta hepatis after Whipple resection is approximately 1.0 cm medial and 1.0 cm posterior compared with its preoperative position. These data suggest that postoperative abdominal computed tomographs are useful in determining treatment volumes of nodal drainage basins after Whipple resection of pancreatic malignancies.

Aggressive multimodality treatment for locally advanced irresectable rectal cancer

BACKGROUND

Local failure rates are high for locally irresectable primary or recurrent colorectal cancer, even when chemoradiation therapy is employed.

AIM

This review evaluates evidence supporting aggressive preoperative chemoradiation followed by maximal surgical resection and intraoperative radiation therapy to achieve disease control and cure for patients with locally advanced irresectable primary or recurrent rectal cancer.

RESULTS

A 5-year survival rate of 42 per cent with a central failure rate of 2 per cent may be achieved in patients with locally irresectable primary rectal cancer. In patients with locally recurrent disease, these values at 5 years are 18 and 28 per cent respectively. The 5-year incidence of distant metastasis remains high, affecting 64 per cent of patients with primary cancer and 75 per cent of those with recurrent cancer.

CONCLUSION

A disease-free surgical resection margin remains paramount to achieve cure. Encouraging trends exist, however, for further evaluation of multimodality therapy as a means of reducing local recurrence of disease.

Intraoperative electron irradiation in the management of pediatric malignancies

BACKGROUND

External beam irradiation (PBRT), especially in children, is limited by the radiosensitivity of normal tissues. Local control remains a problem in abdominopelvic childhood malignancies. Intraoperative electron irradiation (IOERT) has the potential to increase the dose to the tumor, thereby improving local control, without increasing treatment morbidity.

METHODS

Between February 1983 and October 1990, 11 children received IOERT as part of a multidisciplinary treatment program for locally advanced primary or recurrent abdominopelvic malignancies. The 7 boys and 4 girls ranged in age from 2-18 years. Tumor histologies included four neuroblastomas, two desmoid tumors, and one each of the following: embryonal rhabdomyosarcoma, synovial cell sarcoma, neurofibrosarcoma, malignant fibrous histiocytoma, and paraganglioma. Single radiation doses of 10-25 grays were delivered using 6-15-megaelectron volt electron beams to 1-5 IOERT fields. All patients also underwent EBRT and six received chemotherapy.

RESULTS

Eight patients (73%) were alive and disease free at a median follow-up of 99 months (range, 37-126 months). All eight patients who underwent gross total resection were locally controlled. Three patients required surgical intervention for IOERT-related complications and two patients developed neuropathies.

CONCLUSIONS

IOERT as part of a multidisciplinary treatment approach in patients with locally advanced pediatric malignancies appears to enhance local control in those patients in whom a gross total resection is possible. The long term survival rate was encouraging. Further study, with a larger number of patients, appears warranted to more carefully delineate the efficacy and tolerance of IOERT in the pediatric population.

Adjuvant postoperative fluorouracil-modulated chemotherapy combined with pelvic radiation therapy for rectal cancer: initial results of intergroup 0114

PURPOSE

The combination of radiation therapy with fluorouracil (5-FU)-based chemotherapy is generally accepted as appropriate postoperative therapy for patients with adenocarcinomas of the rectum that extend through the bowel wall or with lymph nodes positive for tumor. We attempted to determine whether the efficacy of this postoperative therapy could be improved by the addition of leucovorin and/or levamisole.

METHODS

A total of 1,696 patients were randomized and eligible for treatment with one of four treatment schemes. All patients received two cycles of bolus 5-FU-based systemic chemotherapy followed by pelvic radiation therapy with chemotherapy and two more cycles of the same systemic chemotherapy. Chemotherapy was either 5-FU alone, 5-FU with leucovorin, 5-FU with levamisole, or 5-FU with leucovorin and levamisole.

RESULTS

With a median follow-up duration of 48 months, there is no statistically significant advantage to any of the treatment regimens compared with bolus 5-FU alone. There is evidence of increased gastrointestinal toxicity with the three-drug combination compared with bolus 5-FU alone. Statistical analysis suggests it is very unlikely that either levamisole-containing combination will be shown to be of value with further follow-up evaluation.

CONCLUSION

There is no evidence at present for a beneficial effect of levamisole in the adjuvant treatment of rectal cancer. Definitive evaluation of the effect of the addition of leucovorin to 5-FU and pelvic radiation will require further follow-up evaluation.

Intraoperative radiation therapy in gynecologic cancer: update of the experience at a single institution

PURPOSE

To update the Mayo Clinic experience with intraoperative radiation therapy (IORT) in patients with gynecologic cancer.

METHODS AND MATERIALS

Between January 1983 and June 1991, 39 patients with recurrent or locally advanced gynecologic malignancies received intraoperative radiation therapy with electrons. The anatomical area treated was pelvis (side walls or presacrum) or periaortic nodes or a combination of both. In addition to intraoperative radiation therapy, 28 patients received external beam irradiation (median dose, 45 Gy; range, 0.9 to 65.7 Gy), and 13 received chemotherapy preoperatively. At the time of intraoperative radiation therapy and after maximum debulking operation, 23 patients had microscopic residual disease and 16 had gross residual disease up to 5 cm in thickness. Median follow-up for surviving patients was 43.4 months (range, 27.1 to 125.4 months).

RESULTS

The 5-year actuarial local control with or without central control was 67.4%, and the control within the IORT field (central control) was 81%. The risk of distant metastases at 5 years was 52% (82% in patients with gross residual disease and 33% in patients with only microscopic disease postoperatively). Actuarial 5-year overall survival and disease-free survival was 31.5 and 40.5%, respectively. Patients with microscopic disease had 5-year disease-free and overall survival of 55 and 50%, respectively. Grade 3 toxicity was directly associated with IORT in six patients (15%).

CONCLUSION

Patients with local, regionally recurrent gynecologic cancer may benefit from maximal surgical debulking and IORT with or without external beam irradiation, especially those with microscopic residual disease.

Locally advanced primary colorectal cancer: intraoperative electron and external beam irradiation +/- 5-FU

PURPOSE

For locally advanced primary colorectal cancer, our institution has combined intraoperative electron irradiation (IOERT) with external beam irradiation (EBRT) +/- 5-fluorouracil (5-FU) and surgical resection. Disease control and survival were compared with the current IOERT and prior non-IOERT regimens.

METHODS AND MATERIALS

From April 1981 through August 1995, 61 patients received an IOERT dose of 10-20 Gy, usually combined with 45-55 Gy of fractionated EBRT; 56 had minimum follow-up of 18 months. The amount of residual disease remaining at IOERT after exploration and maximal resection in the 56 patients was gross in 16, < or = microscopic in 39, and unresected in 1.

RESULTS

Survival (SR) and disease control were analyzed as a function of potential prognostic factors. Factors that achieved statistical significance for improved overall survival included treatment sequence of preop EBRT + 5-FU (vs. postoperative EBRT + 5-FU, p = 0.003) and < or = microscopic residual disease after maximal resection (vs. gross residual, p = 0.005). Those that appeared to favorably impact disease-free survival included EBRT + 5-FU (vs. EBRT alone, p = 0.01), < or = microscopic residual (vs. gross, p = 0.0014), and colon site of primary (vs. rectum, p = 0.009). Failures within an irradiation field have occurred in 4 of 16 patients (25%) who presented with gross residual after partial resection vs. 2 of 39 (5%) with < or = microscopic residual after gross total resection (p = 0.01). The significant prognostic factors for a decrease in distant metastases were the same as for disease-free SR with respective p-values of 0.013 (EBRT + 5-FU), 0.008 (microscopic residual), and 0.03 (colon primary). The current data suggests a relationship between IOERT dose and incidence of Grade 2 or 3 neuropathy (< or = 12.5 Gy--1 of 29 or 3%, > or = 15 Gy--6 of 26 or 23%, p = 0.03).

CONCLUSIONS

Both overall survival and disease control appear to be improved with the addition of IOERT to standard treatment. More routine use of systemic therapy is indicated as a component of IOERT containing treatment regimens because the incidence of distant metastases was 50% of patients at risk.

The treatment of locally advanced colon cancer

PURPOSE

The results of therapy for 103 patients with locally advanced colon cancer who received radiotherapy were analyzed to determine the outcome and tolerance of therapy.

METHODS AND MATERIALS

Between 1974 and 1994, 103 patients received radiotherapy and maximal resection of locally advanced colon cancers. Following resection, 50 patients had no residual disease, 18 patients had microscopic residual disease, and 35 patients had gross residual disease. External beam radiotherapy was initiated 1 to 4 months following resection except in two patients who received preoperative radiotherapy. Treatment was delivered to the tumor bed and adjacent lymph nodes using 4 to 18 MV X-rays with doses ranging from 16.2 to 60 Gy. Intraoperative electron radiotherapy (IOERT) was also administered to 11 of the patients with doses ranging from 10 to 20 Gy. Chemotherapy was administered to 77 patients. Follow-up in survivors ranged from 0.5 to 17 years (median: 5.8 years).

RESULTS

The 5-year actuarial local failure rate was 10% for patients with no residual disease, 54% for patients with microscopic residual disease, and 79% for patients with gross residual disease (p < 0.0001). For patients with residual disease, local failure occurred in 11% of patients receiving IOERT compared with 82% of patients receiving only external beam therapy (p = 0.02). The 5-year actuarial survival rate was 66% for patients with no residual disease, 47% for patients with microscopic residual disease, and 23% for patients with gross residual disease (p = 0.0009). The 5-year survival rate in patients with residual disease was 76% for patients receiving IOERT and 26% for patients receiving external beam therapy alone (p = 0.04).

CONCLUSIONS

Patients with locally advanced colon cancer who have had a complete resection have a high probability of local control after external beam irradiation +/- 5 fluorouracil (5FU)-based systemic therapy. The toxicity of therapy can be minimized with attention to treatment technique and dose. Local control and survival rates in patients with residual disease who received IOERT appear to be significantly greater than for those patients who received external beam radiotherapy therapy alone.