Felipe A. Calvo

Intraoperative and external radiotherapy in resected gastric cancer: Updated report of a phase II trial

From September 1984 to August 1991, 48 evaluable patients with resected gastric cancer and apparent disease confined to locoregional area were treated with intraoperative electron beam boost to the celiac axis and peripancreatic nodal areas (15 Gy) and external irradiation (40 to 46 Gy in 4 to 5 weeks) including the gastric bed and upper abdominal nodal draining regions. At the time of evaluation for IORT, the disease was primary in 38 cases, recurrent but resectable in four (anastomosis), and unresectable in four (nodal). Post operative complications were reversible. Acute tolerance to the complete treatment program was acceptable. Late complications included life-threatening events: Six episodes of gastro intestinal bleeding (three of them had an arteriographic documentation of arterioenteric fistula) and nine with severe enteritis (five required reoperation). Other long-term treatment related complications were six cases of vertebral collapse. The median follow-up time for the entire group is 22 months. Locoregional recurrence/persistence of disease has been identified in five patients (three with residual and/or recurrent postsurgical tumor). Systemic tumor progression has been detected in 15 patients (11 in intra-abdominal sites). Overall actuarial survival for patients with positive or negative serosal involvement was 33% versus 56%. It is concluded that the treatment program described is able to induce a high locoregional tumor control rate (100%) when used strictly in an adjuvant setting and might control long term, a small portion of patients not amenable for curative surgery (2 out of 8 patients with confirmed residual post-surgical disease). Gastrointestinal bleeding and enteritis are findings that indicate treatment intensity at the upper limits of tissue tolerance. Assessment of long term tolerance of pancreatic parenchyma and large blood vessels (tissues included in the IRORT field) are pending for longer follow-up and the appropriate selective studies.

Long-term normal tissue effects of intraoperative electron radiation therapy (IOERT) : Late sequelae, tumor recurrence, and second malignancies

PURPOSE To evaluate long-term survivors treated with intraoperative electron radiation therapy (IOERT) as a component, with particular emphasis on analyzing late normal tissue toxicity, second malignancies, and patterns of delayed tumor recurrence. METHODS AND MATERIALS From September 1984 to December 1991, 739 patients were treated with IOERT. One hundred ninety-five patients were alive at least 5 years after IOERT (26%). Patient information regarding late complications related symptoms, incidence of second tumors, and delayed relapses were analyzed. Normal tissue changes were categorized by a modified LENT/SOMA scale (Grade 0-1, Grade 2, and Grade 3-4). Risk of late toxicity was grouped by type and number of cancer treatment modalities employed in each patient: surgery + IOERT alone (17 patients, 9%); IOERT + external radiotherapy +/- chemosensibilization (90 patients, 46%); IOERT +/- external radiotherapy +/- neoadjuvant chemotherapy (+/- previous radiotherapy) (88 patients, 45%). Biologic effective doses (BED) were calculated for alpha/beta = 3.5 for late fibrosis. RESULTS With a mean follow-up time of the surviving patients of 94 months (range: 55-162 months), 99 patients (51%) had Grade 0-1 toxicity, 52 (27%) had Grade 2, and 44 patients (23%) presented Grade 3-4 late normal tissue complications. Risk groups by treatment intensity did correlate with severity of observed toxicity (p < 0.001). BED estimations did not correlate with late normal tissue damage. The tumor type with higher toxicity scores was bone sarcoma (28/46, 60%), in which the estimated BED = 100.5 Gy. Peripheral neuropathy was the dominant IOERT-specific toxicity present in 24 patients (12%). Second malignancies were identified in 8 patients (4%), none inside the IOERT field (3 questionable to be marginal to the external beam radiotherapy volume). In 36 patients (18%), recurrence of the originally treated tumor was detected, including 11 (7%) local relapses. CONCLUSIONS The incidence of late normal tissue complications (50%) and severity (23%) is significant in a cohort of patients surviving more the 5 years after IOERT. The understanding of the contribution of IOERT to late tissue damage requires specific analysis. Peripheral neuropathy is a characteristic finding in IOERT trials. Second malignancies inside the IOERT field were not identified during the study period. The risk of recurrences, including local failures, requires an intensive follow-up of long-term survivors from IOERT trials.

Intraoperative radiotherapy for recurrent and/or residual colorectal cancer

Intraoperative radiotherapy (IORT) is an attractive boosting modality in the combined treatment of recurrent and/or residual colorectal cancer. Twenty seven patients treated with IORT are analysed. Residual disease following resection of the primary tumor was treated in 11 cases (group I). Localized recurrent disease without previous radiotherapy was treated in 11 cases (group II). IORT was used in five additional patients with local recurrences in previously irradiated areas (group III). The treatment program consisted of maximal tumor resection, IORT (10-30 Gy) to the area of residual disease and external beam radiotherapy (46-50 Gy). The median follow-up time for the entire series of patients is 11 months. Local tumor control rates are 90% in group I, 63% in group II and 60% in group III. Toxicity and complications related to IORT observed in this initial experience have been pelvic pain (29%) and lower extremity neuropathy (3%). These early clinical results suggest that the IORT combined with surgery and external beam radiotherapy is feasible in primary and recurrent disease. Local control rates obtained in patients not suitable for curative surgery are encouraging.

Intraoperative radiotherapy during lung cancer surgery: Technical description and early clinical results

A phase I-II study of intraoperative radiotherapy (IORT) for Stage III lung cancer was performed in 34 patients during a period of 58 months. Loco-regional treatment included tumor resection if technically feasible, IORT boost of electron beams using moderate single doses (10-15 Gy) to tumor bearing areas and external photon beam irradiation (46-50 Gy in 5 weeks) using conventional fields. Indications for this study were unresectable hiliar tumors (14, 41%), and mediastinal, hiliar and/or chest wall residual disease following resection (20, 59%). Thirty-four procedures, with 40 IORT fields, have been analyzed to describe the relevant technical aspects and the toxicity. IORT was delivered using acrylic transparent cones of different diameters. Surgical approach consisted in a lateral thoracotomy in all patients (21 right side and 13 left side). Tissues included within the IORT field were: tumor or residual tumor tissues (34, 100%), collapsed lung parenchyma and main bronchus not surgically manipulated (14, 41%), bronchial stump and vascular suture following resection (19, 55%), mediastinal structures (20, 58%), and brachial plexus (1, 3%). The bronchial suture was covered with pleural or pericardial flap after IORT in 10 cases (29%). Life threatening toxicity related to IORT consisted in broncho-pleural fistula (1, 3%) and massive hemoptysis (1, 3%). Other reversible toxic events were acute pneumonitis (12, 85%) and esophagitis (10, 50%). Long term asymptomatic lung fibrosis was detected in 11 cases (32%). Median survival time for the entire group has been 12 months. With a median follow-up time of 12 months the freedom from thoracic recurrence rate is 30% (65% in cases with tumor resection). Projected actuarial survival rates at 4 years were 28% for resected group and 7% for unresected cases. This experience supports IORT as a feasible alternative modality to be used in the management of locally advanced lung cancer. Tolerance of thoracic organs to moderate doses of IORT appeared to be adequate and local control is achieved in certain patients. These results deserve further investigation and confirmation trials.

Intraoperative and external beam radiotherapy in advanced resectable gastric cancer: Technical description and preliminary results

Twenty-two patients with resectable gastric cancer treated with intraoperative radiotherapy and external beam irradiation, in a Phase I-II oriented study, were analyzed. Tumor Stages were III & IV in 18 cases (82%). Tumor histology was described as diffuse undifferentiated type in 14 cases (63%). Following surgical resection of the primary tumor, IORT 15 Gy was delivered in the celiac axis area, using high energy electron beams ranging from 9 to 20 MeV. External beam irradiation fields covered the draining nodal areas of the upper abdomen and the gastric bed. There were no postoperative deaths. Reversible postoperative complications were recorded in 14 patients (63%). Long term complications observed were vertebral collapse and liver hemangiomas. First sites of recurrence have been: hepatic hilum (three cases), peritoneum combined with central axis nodes (two cases), liver metastasis (one case), and lung metastasis (one case). Survival data shows a follow-up period ranging from 1+ to 33+ months, with a median survival time for the entire group of 13+ months. At the time of this report, 16 patients (72%) are still alive and six have died (four from progressive malignant disease and two from intercurrent disease). From this preliminary data, it can be concluded that a combined approach with surgical resection, intraoperative radiotherapy, and external beam irradiation is feasible in advanced gastric carcinoma, and is not limited by toxicity or any complications observed. Despite this intense loco-regional therapeutic approach, the upper abdominal failure rate has been demonstrated in 22% of the cases.

Intraoperative radiotherapy in recurrent gynecological cancer

A retrospective analysis to assess the feasibility and clinical tolerance of intraoperative radiotherapy (IORT) in the treatment of recurrent gynecologic cancer is reported. From February 1985 to September 1992, 26 patients with recurrent gynecologic tumors entered this trial. The clinical experience comprises two different categories of disease situations: tumors relapsing after full dose radiation therapy (group I) and recurrent disease to previous surgery (group II). Cervical carcinoma was the initial tumor site of involvement in 18 patients (69%). Treatment consisted in maximal surgical resection + IORT boost (10-25 Gy) to the high-risk areas for recurrence. Non previously irradiated patients also received external beam irradiation (EBRT) (+/- chemotherapy) pre- or postoperatively. IORT-related toxicity was one episode of motor neuropathy. Local control rates have been 33% and 77%, respectively in groups I and II. The 4-year actuarial overall survival in Group I is 7% and 6-year actuarial overall survival in Group II is 33%. The addition of IORT to surgical debulking achieves modest local control and long-term survival rates if tumor-free margins cannot be obtained in previously irradiated patients. Combined EBRT (+/- chemotherapy) maximal surgical resection plus IORT could render some long-term survivors among those surgical recurrent patients not candidates for radical surgery with curative intent.

27 Intra-operative radiation therapy in the treatment of pelvic malignancies: a preliminary report

Local control of advanced pelvic malignancies, particularly when complete surgical resection is not feasible, is often impeded by dosage limitations in radiation therapy and the intolerance to radiation of normal tissues. This is a preliminary report on the feasibility of improved local control in pelvic malignancies treated by intra-operative radiation therapy, as a radiation boost, in addition to conventional surgical resection and external beam radiation therapy. Fifteen gynaecological malignancies (five cervix, five uterus, four ovary, and one vulva) from Rush Medical College and the University of Navarre, as well as 36 other pelvic malignancies (32 colorectal, 4 genito-urinary) from Rush Medical College were reviewed. All tumours were advanced or recurrent, and all patients were felt to be at high risk of local failure. IORT was administered at a dose range of 10-26 Gy. Our data suggest that the probability of local control improves when IORT is used for primary and for microscopic disease, when the tumour is at least partially resectable, and when the total dose given in IORT and external beam radiation exceeds 70 Gy.

Extremity and Trunk Soft Tissue Sarcomas

Management of soft-tissue sarcomas of the extremities and trunk is optimally accomplished through a multidisciplinary team evaluation of each patient because of the diverse and complex nature of each clinical scenario. A team of orthopedic or surgical oncologists, radiation oncologists, medical oncologists, plastic surgeons, pathologists, and radiologists consider multiple issues including tumor stage, grade, location, and histologic type of tumor, as well as feasibility of a limb-sparing surgery, timing of radiation, and the patient’s performance status and comorbid illnesses. The rarity of these tumors in combination with the variety of presentation in extremity and truncal soft-tissue sarcomas limits the amount of prospective data available to reliably outline the management of all situations, and hence, there is a range of approaches utilized around the world today.

Gastric IORT With or Without EBRT

Gastric cancer has experienced a marked change in prevalence during the last decades. Although in some countries, as in the Far East, gastric cancer continues to be a national health problem, the incidence in most Western countries is decreasing. Most importantly, whereas the overall incidence of gastric cancer has decreased in Europe and the United States, there has been an increase in the relative percentage of proximal gastric adenocarcinomas and adenocarcinomas arising in the gastroesophageal junction. With the exception of Japan, where mass screening programs have increased the number of patients diagnosed of early gastric cancer, diagnosis at an advanced stage is the rule. Approximately 50–75% of the patients who have gastric resection for cancer have serosal invasion and/or lymph node involvement. This helps to explain why cure rates have remained unchanged for decades in spite of improvements in oncologic therapy. Investigators should consider that both accrual and design of future trials in gastric cancer will probably be affected by these epidemiological trends.

IORT for Bone Sarcomas

Bone sarcomas are rare entities in clinical oncology, in which the histological subtype and site of involvement define the natural history of the disease and in particular the appropriate treatment strategy (1). Ewing sarcoma is a chemo- and radiation-sensitive disease in which combined-modality therapy (more recently including a surgical component) is mandatory for radical management (2). Osteosarcoma survival rates have been significantly improved by adjuvant chemotherapy and extremity preservation rates by neoadjuvant chemotherapy (3). Other uncommon bone sarcomas such as malignant fibrous histiocytoma (MFH) or chondrosarcoma are considered marginally sensitive to chemotherapy or radiotherapy and the primary radical treatment modality is surgery (4,5).A universal feature in the natural history of bone sarcomas is the tendency to involve the extraosseous soft tissue and neurovascular structures once the tumor growth and infiltration acquires a certain size.