Intraoperative radiotherapy in recurrent gynecological cancer

Outcomes and toxicity in re-irradiation of gynecologic cancer: Systematic review of the Italian association of radiation and clinical oncology (AIRO)

AIMS

The aim of this study was to provide a literature review on the efficacy and safety of reirradiation(re-I) of locoregional recurrences in gynecological malignancies.

METHODS

A computerized literature search was performed in 4 electronic databases (1993-2020). Random-effects models and a tendency towards high heterogeneity (Cochran Q chi-square test and the I2 statistic) were used. A meta-analysis technique over single and multi-arm studies was performed to determine the pooled acute and late toxicity rate ≥ G3, locoregional control (LC), and overall survival (OS).

RESULTS

Out of 178 articles, only 18 articles accounting for 820 patients (pts) met the inclusion criteria. Outcomes were evaluable for 522 patients. Subgroup analyses highlighted moderate to high heterogeneity among studies. BT (Brachytherapy) showed a 2y OS of 63% (95% CI, 55 to 71 p = 0,36) and 5y OS of 42% (95% CI, 35 to 50, p = 0,43) with 1y-2y-3y LC of 74 (95% CI, 62 to 75, p = 0.04)49% (95% CI, 40 to 58, p = 0.38) and 48% (95% CI, 39 to 58, p = 0,45) respectively. Chemotherapy does not improve SBRT outcomes: BT showed a G3- G4 toxicities rate was of26% (95% CI: 8-49%); studies on SBRT re-I showed a G3-G4 toxicity around of 20% if combined with CHT, and <10 when alone.

CONCLUSION

A large heterogeneity among studies was revealed, but showing promising results in terms of safety and feasibility. BT resulted the best kind of radiation therapy delivery in terms of clinical outcome and comparable to the SBRT technique in terms of toxicities.

Multidisciplinary therapy for patients with locally oligo-recurrent pelvic malignancies

PURPOSE

To analyze prognostic factors and long-term outcomes in patients with locally recurrent pelvic cancer (LRPC) treated with a multidisciplinary approach.

METHODS AND MATERIALS

From January 1995 to December 2011, 81 patients [rectal (47 %); gynecologic (39 %); retroperitoneal sarcoma (14 %)] underwent extended surgery [multiorgan (58 %), bone (35 %), vascular (9 %), soft tissue (63 %)] and intraoperative electron beam radiation therapy (IOERT) to treat recurrent tumors in the pelvic region. Thirty-five patients (43 %) received external beam radiotherapy (EBRT). Survival was estimated using the Kaplan-Meier method, and risk factors were identified using univariate and multivariate analysis.

RESULTS

Median follow-up was 39 months (6-189 months); the 1- 3- and 5-year rates of locoregional control (LRC) were 83, 53, and 41 %, respectively. Univariate Cox proportional hazard analysis revealed worse LRC in patients who did not receive integrated EBRT as rescue treatment of pelvic recurrence (p = 0.003) or underwent non-radical resection (p = 0.01). In the multivariate analysis EBRT, non-radical resection, and tumor fragmentation retained significance (p = 0.002, p = 0.004, and p = 0.05, respectively).

CONCLUSIONS

Radical resection, absence of tumor fragmentation and addition of EBRT for rescue are associated with improved LRC in patients with LRPC. Our results suggest that this group can benefit from EBRT combined with extended surgical resection and IOERT.

Intraoperative radiotherapy electron boost in advanced and recurrent epithelial ovarian carcinoma: a retrospective study

BACKGROUND

Relapses of epithelial ovarian carcinoma (EOC) have a poor prognosis and are almost always fatal. The aim of this study was to evaluate the clinical outcome and toxicity of intraoperative electron beam radiation therapy (IOERT) in advanced and recurrent EOC.

METHODS

Forty-five women with EOC were treated with IOERT. Twenty-five patients had primary disease (PD) without distant metastasis at IOERT, and 20 patients had an isolated local recurrence (ILR) after surgery. All 45 patients in this series underwent optimal cytoreductive (≤ 1 cm) surgery. The whole pelvic (WP) radiotherapy was intraoperatively delivered using 12 Mev electron beam; 43 patients received 18-20 Gy and two patients received 10 Gy. Thirty-three patients received postoperateive intraperitoneal (IP) chemotherapy, while seven patients received intravenous (IV) chemotherapy. Five patients refused concurrent chemotherapy. Overall survival (OS) rates were analyzed using the Kaplan-Meier method.

RESULTS

Tumor recurrence and metastasis were observed in 16 patients (35.6%). Of those, 14 patients (31.1%) relapsed and two patients (4.4%) had distant metastasis alone. Eight of 25 (32%) local failures were observed in the PD group, as compared to 6/20 (30%) in the ILR group (P = 0.885). Actuarial local control at five year follow-up was 31/45 (68.9%). Seventeen of the total 45 (37.8%) patients died. Nine of 25 (36%) in the PD group died, as compared to 8 of 20 (40%) in the ILR group. The 5-year OS and disease-free survival (DFS) rates were 28/45 (62.2%) and 25/45 (55.6%), respectively. In the PD group, the 5-year OS and DFS rates were 16/25 (64%) and 14/25 (56%) (P > 0.05, vs. the ILR group at 12/20 and 11/20, respectively). The OS and DFS in the IOERT plus IP group were 25/33 (75.8%) and 23/33 (69.7%), respectively, which were superior to the rates achieved with IOERT plus IV chemotherapy (P < 0.05, 2/7 and 1/7, respectively). The major complication of IOERT was neuropathy. Five (11.1%) patients developed peripheral neurotoxicity.

CONCLUSIONS

IOERT may be feasible and effective as a boosting technique for advanced and recurrent ovarian cancer. IOERT plus IP chemotherapy may achieve high locoregional disease control and survival benefit with a low risk of toxicity. Peripheral nerves in the IOERT field are dose-limiting structures requiring nerve protection policies or a dose compromise to ensure against severe neurological damage.

Long-Term Survivors Using Intraoperative Radiotherapy for Recurrent Gynecologic Malignancies

PURPOSE

To analyze the outcomes of therapy and identify prognostic factors for patients treated with surgery followed by intraoperative radiotherapy (IORT) for gynecologic malignancies at a single institution.

METHODS AND MATERIALS

We performed a retrospective review of 36 consecutive patients treated with IORT to 44 sites with mean follow-up of 50 months. The primary site was the cervix in 47%, endometrium in 31%, vulva in 14%, vagina in 6%, and fallopian tubes in 3%. Previous RT had failed in 72% of patients, and 89% had recurrent disease. Of 38 IORT sessions, 84% included maximal cytoreductive surgery, including 18% exenterations. The mean age was 52 years (range, 30-74), mean tumor size was 5 cm (range, 0.5-12), previous disease-free interval was 32 months (range, 0-177), and mean IORT dose was 1,152 cGy (range, 600-1,750). RT and systemic therapy after IORT were given to 53% and 24% of the cohort, respectively. The outcomes measured were locoregional control (LRC), distant metastasis-free survival (DMFS), disease-specific survival (DSS), and treatment-related complications.

RESULTS

The Kaplan-Meier 5-year LRC, DMFS, and DSS probability for the whole group was 44%, 51%, and 47%, respectively. For cervical cancer patients, the Kaplan-Meier 5-year LRC, DMFS, and DSS estimate was 45%, 60%, and 46%, respectively. The prognostic factors found on multivariate analysis (p <or= 0.05) were the disease-free interval for LRC, tumor size for DMFS, and cervical primary, previous surgery, and locoregional relapse for DSS. Our cohort had 10 Grade 3-4 complications associated with treatment (surgery and IORT) and a Kaplan-Meier 5-year Grade 3-4 complication-free survival rate of 72%.

CONCLUSIONS

Survival for pelvic recurrence of gynecologic cancer is poor (range, 0-25%). IORT after surgery seems to confer long-term local control in carefully selected patients.

Perioperative high-dose-rate brachytherapy in locally advanced and recurrent gynecologic cancer: Initial results of a phase II trial

BACKGROUND

This study was undertaken to determine the feasibility of perioperative high-dose-rate brachytherapy (PHDRB) as an adjunct to salvage surgery in primary advanced or recurrent gynecologic cancer.

METHODS

Twenty-five patients with either locally advanced (n = 4) or recurrent (n = 21) gynecologic cancer suitable for salvage surgery were included. Unirradiated patients were treated with preoperative chemoradiation followed by salvage surgery and PHDRB (R0 and R1 resections receiving 16 or 24 Gy, respectively). Previously irradiated patients were treated with salvage surgery and PHDRB alone with 32 or 40 Gy for R0 or R1 resections, respectively.

RESULTS

Resections were categorized as R0 in 9 patients (36.0%) and R1 in 16 (64.0%). Four previously irradiated patients suffered fatal pelvic bleeding between 8 and 13 months after surgery and PHDRB. After a median follow-up of 20 months (3-55+), the 4-year actuarial local and pelvic controls were 88.1% and 80.8%, respectively. The 4-year distant metastases-free survival was 40.9%. Four-year actuarial overall survival was 34.0%, with a median survival of 27.1 months (95% confidence interval: 17.5-36.8).

CONCLUSIONS

Local and pelvic control results are excellent for this very high-risk-disease population. PHDRB dose in previously irradiated patients has been shifted to the closest lower level due to unacceptable vascular toxicity.

Radical pelvic resection and intraoperative radiation therapy for recurrent endometrial cancer: Technique and analysis of outcomes

OBJECTIVE

To describe the technique and assess outcomes and morbidity following radical resection combined with intraoperative electron radiation therapy (IOERT) in patients with recurrent endometrial cancer.

METHODS

From 1986 to 2002, 25 patients received treatment including radical resection and IOERT for recurrent endometrioid, endometrial cancer. Relevant clinical information was extracted through retrospective chart review.

RESULTS

Treatment prior to referral included radiation in 56% and either a secondary surgery or chemotherapy in 48%. External radiation (EBRT) was administered in addition to IOERT in 84%. Radical procedures performed at the time of IOERT included resection of the pelvic sidewall en bloc with the obturator nerve, external iliac vein, psoas, iliacus, or obturator internus muscles, ureter, or boney ileum. Seven patients required exenteration in combination with resection of the pelvic sidewall. The median IOERT dose was 1500 cGy (range 1000-2500 cGy). Overall five-year survival was 47% vs. 71% for those with a gross total resection but close margins. Two patients with recurrences limited to the para-aortic area are alive without evidence of disease at 54 and 71 months. Proportional hazards modeling showed concurrent EBRT, tumor size after resection, grade, and age to be associated with improved survival. The most common complications were peripheral neuropathy, functional ureteral obstruction, and fistula formation.

CONCLUSIONS

With an aggressive treatment approach including radical resection combined with IOERT, long-term survival is possible in a significant number of patients with localized recurrent endometrial cancer. Preoperative radiation paired with complete surgical resection utilizing extended procedures is paramount to achieving optimal outcomes.

Intraoperative radiation therapy in recurrent ovarian cancer

PURPOSE

To evaluate disease outcomes and complications in patients with recurrent ovarian cancer treated with cytoreductive surgery and intraoperative radiation therapy (IORT).

METHODS AND MATERIALS

A retrospective study of 24 consecutive patients with ovarian carcinoma who underwent secondary cytoreduction and intraoperative radiation therapy at our institution between 1994 and 2002 was conducted. After optimal cytoreductive surgery, IORT was delivered with orthovoltage X-rays (200 kVp) using individually sized and beveled cone applications. Outcomes measures were local control of disease, progression-free interval, overall survival, and treatment-related complications.

RESULTS

Of these 24 patients, 22 were available for follow-up analysis. Additional treatment at the time of and after IORT included whole abdominopelvic radiation, 9; pelvic or locoregional radiation, 5; chemotherapy, 6; and no adjuvant treatment, 2. IORT doses ranged from 9-14 Gy (median, 12 Gy). The anatomic sites treated were pelvis (sidewalls, vaginal cuff, presacral area, anterior pubis), para-aortic and paracaval lymph node beds, inguinal region, or porta hepatitis. At a median follow-up of 24 months, 5 patients remain free of disease, whereas 17 patients have recurred, of whom 4 are alive with disease and 13 died from disease. Five patients recurred within the radiation fields for a locoregional relapse rate of 32% and 12 patients recurred at distant sites with a median time to recurrence of 13.7 months. Five-year overall survival was 22% with a median survival of 26 months from time of IORT. Nine patients (41%) experienced Grade 3 toxicities from their treatments.

CONCLUSION

In carefully selected patients with locally recurrent ovarian cancer, combined IORT and tumor reductive surgery is reasonably tolerated and may contribute to achieving local control and disease palliation.

Surgical resection of locally recurrent cervical cancer: a single institutional 70 patient series

Pelvic recurrence of cervical cancer is a life-threatening situation and only local control can provide hope for remission. The aim of this study was to evaluate the role of surgery in the treatment of cervical cancer recurrence. This retrospective study analyzed a series of 70 patients who underwent resection of cervix locoregional recurrence. Thirteen patients had palliative salvage surgery for pelvic complications. Twenty-nine resections were considered as curative. Fifty recurrences required pelvic exenterations. The hospital mortality rate was 9% and the morbidity rate was 44%. Overall 5-year actuarial survival rate was 23%. Survival was significantly higher: (a) after curative resection and (b) after centropelvic recurrence resection. Local control was obtained in 48% of the cases and 13 patients are alive with a median follow-up of 75 months. In conclusion, the results of this small and heterogen series seem to justify an attempt to resection for centropelvic recurrences whenever possible. Palliative surgery should be reserved to salvage therapy and highly selected patients.

Intraoperative radiotherapy electron boost followed by moderate doses of external beam radiotherapy in resected soft-tissue sarcoma of the extremities

PURPOSE

To analyze the patterns of failure and the toxicity profile of intraoperative electron beam radiotherapy (IOERT) after resection of soft tissue sarcomas of the extremities (STS).

PATIENTS AND METHODS

Forty-five patients with extremity STS were treated with IOERT and moderate-dose postoperative radiotherapy (45-50 Gy). Twenty-six patients were treated for primary disease (PD) and 19 patients for an isolated recurrence (ILR). Tumor size was >5 cm (maximum diameter) in 36 patients (80%), and high-grade histology in PD patients was present in 14 patients (54%). In nine patients, IOERT was used alone, due to previous irradiation or patient refusal. Chemotherapy (neoadjuvant and/or adjuvant) was mainly given to high-grade tumors.

RESULTS

Nine patients relapsed in the extremity (20%), and 12 patients in distant sites (28%). Actuarial local control at 5 years was 88% for patients with negative/close margins and 57% for patients presenting positive margins (P=0.04). Five patients (11%) developed neuropathy associated with the treatment. Extremity preservation was achieved in 40 patients (88%). With a median follow-up of 93 months (range: 27-143 months) for the patients at risk, 25 patients remain alive (a 7-year actuarial survival rate of 75% for PD and 47% for ILR; P=0.01).

CONCLUSIONS

IOERT combined with moderate doses of external beam irradiation yields high local control and extremity preservation rates in resected extremity STS. Peripheral nerves in the IOERT field are dose-limiting structures requiring a dose compromise in the IOERT component to avoid severe neurological damage.

Fractionated perioperative high dose rate brachytherapy using a tissue equivalent bendy applicator

Intraoperative radiation techniques allow an additional local dose in areas at high-risk for local failure. With brachytherapy techniques, perioperative radiation can be fractionated. Fractionated treatment might offer an interesting alternative to a single dose, both to increase the therapeutic ratio and to protect late reacting tissues at risk. The dose distribution for brachytherapy applicators can be optimized using spacer materials. In this prospective study a new tissue equivalent bendy applicator (TEBA) that can remain in situ for several days is introduced, and the feasibility of fractionated perioperative high dose rate (HDR) brachytherapy is examined. 31 patients with different tumours (soft tissue sarcoma, Ewings sarcoma, rectal cancer, and locally infiltrating diseases) were treated. The TEBA was applied, depending on resection status and intraoperative findings. Planning was based on digitized radiographs and CT scans. Perioperative HDR brachytherapy was performed using an individual treatment schedule. In 29 patients perioperative radiation was given and in 26 cases fractionated brachytherapy application was possible. TEBA application time varied from 1 day to 11 days. During this time between 1 and 8 fractions were given with total doses from 10 Gy to 25 Gy. Fractionated perioperative brachytherapy with this technique is feasible and adequate. Further studies will show whether fractionated perioperative treatment using the TEBA technique fulfils its theoretical advantages over single dose intraoperative radiotherapy by decreased late toxicity and increased local tumour control.

Intraoperative electron beam radiotherapy during radical surgery for locally advanced and recurrent cervical cancer

OBJECTIVE

The goal of this study was to determine the toxicity patterns and clinical usefulness of intraoperative electron beam radiotherapy (IOERT) in patients with unfavorable-outcome cervical cancer.

METHODS

From January 1986 to June 1999, 67 patients (36 recurrent, 31 primary disease) were treated with IOERT. Previously unirradiated patients received preoperative chemoradiation to 45 Gy with cisplatin 20 mg/m(2) and 5-fluorouracil 1000 mg/m(2). IOERT median dose was 12 Gy for primary disease (range: 10-25) and 15 Gy for recurrent disease (range: 10-20).

RESULTS

The 10-year control rate within the area treated with IOERT ("in-field" (IF)) for the entire group was 69.4, with 92.8 and 46.4% 10-year IF control rates for the primary and recurrent patients, respectively. IF control rate correlated with involvement of the parametrial margin (P = 0.001), amount of residual disease (P = 0.001), and pelvic lymph node involvement (P = 0.032). The overall incidence of toxic events that might be attributable to IOERT was 14.9%. Chronic pain was observed in 8 of 67 evaluable patients (11.9%) and motor neuropathy of the lower extremity in one patient (3.2%).

CONCLUSIONS

IOERT is a valuable boosting technique in the management of advanced but resectable cervical cancer. Patients, especially recurrent cases, with positive lymph nodes, parametrial involvement, and/or incomplete resections have poor local control rates despite IOERT at the doses used in this study.

Radical surgical resection and high-dose intraoperative radiation therapy (HDR-IORT) in patients with recurrent gynecologic cancers

OBJECTIVE

To determine the outcome for patients with recurrent gynecologic tumors treated with radical resection and combined high-dose intraoperative radiation therapy (HDR-IORT).

METHODS AND MATERIALS

Between November 1993 and June 1998, 17 patients with recurrent gynecologic malignancies underwent radical surgical resection and high-dose-rate brachytherapy. The mean age of the study group was 49 years (range 28-72 years). The site of the primary tumor was the cervix in 9 (53%) patients, the uterus in 7 (41%) patients, and the vagina in 1 (6%) patient. The treatment for the primary disease was surgery with or without adjuvant radiation in 14 (82%) patients and definitive radiation in 3 (18%) patients. The current surgery consisted of exenterative surgery in 10 (59%) patients and tumor resection in 7 (41%) patients. Complete gross resection was achieved in 13 (76%) patients. The mean HDR-IORT dose was 14 Gy (range 12-15). Additional radiation in the form of permanent Iodine-125 implant was given to 3 of 4 patients with gross residual disease. The median peripheral dose was 140 Gy.

RESULTS

With a median follow-up of 20 months (range 3-65 months), the 3-year actuarial local control (LC) rate was 67%. In patients with complete gross resection, the 3-year LC rate was 83%, compared to 25% in patients with gross residual disease, p < 0.01. The 3-year distant metastasis disease-free and overall survival rates were 54% and 54%, respectively. The complications were as follows: gastrointestinal obstruction, 4 (24%); wound complications, 4 (24%); abscesses, 3 (18%); peripheral neuropathy, 3 (18%); rectovaginal fistula, 2 (12%); and ureteral obstruction, 2 (12%).

CONCLUSION

Radical surgical resection and combined IORT for patients with recurrent gynecologic tumors seems to provide a reasonable local-control rate in patients who have failed prior surgery and/or definitive radiation. Patient selection is very important, however, as only those patients with complete gross resection at completion of surgery appear to benefit most from this radical approach in the salvage setting.

Pulsed dose rate (PDR) brachytherapy as salvage treatment of locally advanced or recurrent gynecologic cancer

PURPOSE

Pulsed dose rate (PDR) brachytherapy is a new treatment option permitting dose distribution optimization in interstitial implants. It possesses the advantage of equipment simplification and radiation protection to the staff, compared to the manually afterloading technique. This study presents the first clinical results from The Finsen Center with PDR-brachytherapy in patients with locally advanced or recurrent gynecologic cancer.

METHODS AND MATERIALS

Between June 1993 and August 1996, 34 patients with gynecologic malignancies (22 pelvic recurrences, 12 primary locally advanced) have been treated with external irradiation, four-field box technique, to 46 Gy/23 fractions, 5 F/week and 192Ir-interstitial PDR-brachytherapy in pulses of 0.6 Gy, one pulse per hour to a total of 30 Gy. The Martinez Universal Perineal Interstitial Template applicator was used for all implantations.

RESULTS

The overall complete response rate was 74%. At median 14 months follow-up (range 3-40) 15 patients were alive with no evidence of disease. Seven of 14 patients with a second recurrence or progressive disease were still alive. The overall 1- and 2-year survival was 71% and 63%, respectively. There was no difference in survival probability when stratifying the patients by primary diagnosis (recurrent vs. primary advanced), relapse locations (central vs. central + pelvic wall mass) or treatment volume. Seventeen chronic grade III complications were observed in 10 patients. Large treatment volumes significantly correlated to severe gastrointestinal complications. Fifteen of 17 chronic grade III complications were observed in patients treated for recurrent disease.

CONCLUSION

PDR-brachytherapy in combination with external irradiation is an effective treatment option for patients with locally advanced or recurrent gynecologic cancer, although substantial toxicity is observed in patients with large treatment volumes and recurrent disease.

Radiation therapy of pelvic recurrence after radical hysterectomy for cervical carcinoma

OBJECTIVES

To evaluate the efficacy of radiation therapy and potential prognostic factors in patients treated for pelvic recurrence of cervical carcinoma after radical hysterectomy.

MATERIALS

The records of 50 patients treated between 1964 and 1994 for an isolated pelvic recurrence of cervical carcinoma a median of 10.5 months after initial radical hysterectomy were retrospectively reviewed. Patients were categorized according to the extent of disease on clinical examination as group 1, mucosal involvement only (5); group 2, paravaginal extension (11); group 3, central recurrence with pelvic wall extension (13); and group 4, recurrences limited to the pelvic sidewall (21). Seven patients with group 3 or 4 disease who had a poor performance status were treated with palliative intent using hypofractionated radiotherapy. The remaining 43 patients were treated with curative intent, 33 with radiotherapy only and 10 with a combination of cisplatin-based chemotherapy and radiotherapy. Survival rates were calculated from the date of initial recurrence. Median follow-up of surviving patients was 109 months.

RESULTS

The overall 5-year survival rate was 33% for all 50 patients (median survival, 18 months), 39% for the 43 patients treated with curative intent, and 25% for patients with isolated sidewall recurrences treated with curative intent. The survival rate was 69% for patients with group 1 and 2 disease and 18% for those treated with curative intent for group 3 disease (P = 0.07). The survival rate was better for patients with recurrent squamous carcinomas (51%) than for those with adenocarcinomas (14%) (P = 0. 05). Three group 4 patients who survived more than 5 years were treated with external-beam radiation alone. Eight-one percent of patients who had a second recurrence had evidence of disease progression. Three patients experienced late treatment complications.

CONCLUSIONS

Patients who experience an isolated recurrence of cervical cancer after initial radical hysterectomy have an excellent prognosis if disease does not involve the pelvic wall. Occasional long-term survivors of recurrent disease involving the pelvic wall justify an aggressive treatment approach.

Intraoperative irradiation delays anastomotic repair in rat colon

BACKGROUND

There exists a growing interest in intraoperative radiation therapy as a treatment modality for large-bowel cancer. Since such therapy could interfere with wound repair, we investigated its effects on early healing of colonic anastomoses.

METHODS

After resection of 1 cm of colon, rats were irradiated with a single dose of 25 Gy, either to the proximal limb (P group) or to both proximal and distal limbs of the bowel (PD group) before anastomotic construction. Both groups were compared with a sham-irradiated control group. Animals were killed 3, 7, or 14 days after operation, and healing was assessed by mechanical and biochemical (collagen) parameters.

RESULTS

Three days after operation, bursting pressure was significantly lowered in the P group, whereas in the PD group both bursting pressure and breaking strength were strongly reduced. At day 7, the breaking strength was still reduced in the PD group, but not significantly so in the P group. The collagen synthetic capacity of the anastomotic segments was significantly lowered in both irradiated groups at day 3, resulting in a diminished collagen concentration in the actual wound area after 7 days. At 14 days after operation, no differences in strength were found between control and irradiated groups, while anastomotic hydroxyproline levels were significantly higher in both the P and PD groups than in the control group.

CONCLUSIONS

High-dose intraoperative radiation therapy delays the healing of colonic anastomoses; it transiently reduces strength, probably as a result of a diminished accumulation of collagen.

Intraoperative radiation therapy (IORT) for head and neck cancer

PURPOSE

To determine the efficacy of intraoperative radiation therapy (IORT) for patients with advanced or recurrent head and neck cancer.

METHODS AND MATERIALS

Intraoperative radiation therapy was given at 30 sites in 25 patients using a 6-18 MeV electron beam with or without conventional external beam irradiation. A single dose of 10-30 Gy was delivered after surgical resection. Sites treated with IORT were classified into three types after surgical resection: gross residual disease (GR, n = 7), microscopic residual disease (MR, n = 12), and close margin (CM, n = 11). Local control rate, patterns of recurrence, survival rate, and complications were analyzed.

RESULTS

The 2-year cumulative local control rate within the IORT port was 54.1% for all cases, 0% for GR, 54.5% for MR, and 81.8% for CM. There were significant differences between GR and MR (p < 0.05), and GR and CM (p < 0.01). The majority of the failures inside the IORT port were associated with recurrence outside the port. Distant metastases occurred in five patients. Four of these had GR. The 2-year cumulative survival rate was 45.1% for all, 0% for GR, 33.0% for MR, and 70.0% for CM. Five patients (22%) experienced late complications. The 2-year cumulative complication rate was 32.8%. Four sites developed osteoradionecrosis and three developed carotid artery blowout. Incidence of complications increased when patients received over 20 Gy with a single dose of IORT.

CONCLUSIONS

Considering both therapeutic ratio and patterns of failure, it is not suitable to treat patients with gross residual disease with IORT. We could not firmly determine the therapeutic value of IORT for patients with microscopic residual disease and close margin. For this subset, further study of moderate dose (less than 20 Gy) IORT combined with adequate postoperative irradiation is needed.