Lower abdominal radiotherapy for stages I, II, and selected III epithelial ovarian cancer: 20 years experience

Radiotherapy for isolated recurrent epithelial ovarian cancer: A single institutional experience

AIM

To evaluate the efficacy and toxicity of external beam radiotherapy (RT) for isolated recurrent epithelial ovarian cancer (EOC).

METHODS

Twenty-four isolated recurrent EOC patients treated with RT at Osaka University Hospital between January 2000 and January 2017 were included in the current study. Data regarding the primary or recurrent diseases, follow-up findings, and efficacy or toxicities of RT were collected and retrospectively analyzed. Survival rates were calculated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

Their median age was 59 years. Most patients had International Federation of Gynecology and Obstetrics stage III-IV diseases at the initial diagnosis. Histologically, serous adenocarcinoma was predominant, followed by clear cell adenocarcinoma. All patients had received at least one regimen of platinum-based chemotherapy; 8 were platinum-sensitive relapse and the others were platinum-resistant. Lymph nodes were the most common sites of recurrence, and the median tumor size was 25.5 mm. The median total dose of RT administered was 54 Gy, with a median daily dose of 2 Gy. RT was well-tolerated, and no patients experienced Grade 3/4 toxicities. The in-field overall response rate was 58.3% (14/24), the median regression rate was -40.2% (range: -100 to 0) and the median survival period after RT was 17 months. The 1-year survival and local progression-free survival rates after RT were 66.7% and 45.8%, respectively.

CONCLUSION

RT showed significant antitumor effect against isolated recurrent EOC without causing severe toxicities. Prospective studies with sufficient statistical power are warranted to further evaluate the role of RT in this patient population.

Dosimetric Comparisons of Three-dimensional Conformal Radiotherapy, Intensity-Modulated Radiotherapy, and Helical Tomotherapy in Whole Abdominopelvic Radiotherapy for Gynecologic Malignancy

Objectives

The goal of this study was to dosimetrically compare 3-dimensional radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), and helical tomotherapy (TOMO) plans for whole abdominopelvic radiotherapy (WART) in patients with gynecologic cancer.

Methods

Ten patients were selected for WART planning. Doses were prescribed to planning target volumes (PTVs) as the followings: 30 Gy to PTV-whole abdominopelvis (PTV-WA), 40 Gy to PTV-para-aortic lymph node (PTV-PALN), 44 Gy to PTV-pelvis, and 50 Gy to gross target volume (GTV) in 20 fractions. Dose to whole liver, both kidneys, and spinal cord were constrained below each tissue tolerance, and bone marrow (BM)-sparing technique was adopted in IMRT and TOMO. Dosimetric parameters and treatment times were compared among plans.

Results

Calculated doses in TOMO came most closely to the prescribed dose for coverage of PTV-WA, PTV-PALN, PTV-pelvis, and GTV compared to 3DCRT, and IMRT. In normal organs, TOMO had significantly better dosimetric profiles compared to IMRT and 3DCRT. TOMO significantly reduced V20Gy, and mean dose of whole liver, both kidneys, and spinal cord. The use of BM-sparing technique (BMS) did not impair coverage of target volume in IMRT and TOMO. While IMRT showed no differences of irradiated BM dose using BMS, TOMO with BMS reduced half V20Gy of BM compared to TOMO without BMS.

Conclusions

TOMO showed dosimetric superiority in target coverage, sparing BM, and other normal organs compared to 3DCRT and IMRT. Clinical experiences will be needed for evaluation of feasibility of WART using TOMO in patients with gynecologic cancer.

Radiation fields in gynecologic oncology: correlation of soft tissue (surgical) to radiologic landmarks

OBJECTIVES

(1). To determine if radiation fields defined by bony structure landmarks correlate to anatomic boundaries of lymph node dissection marked intraoperatively; and (2). to determine if a patient's body mass index (BMI) correlates with these anatomic or radiographic boundaries.

METHODS

One hundred patients undergoing exploratory laparotomy with pelvic and paraaortic lymph node dissection had three medium hemoclips placed at vascular junctions considered of clinical significance to lymph node dissection: insertion of the left ovarian vein into the renal vein, insertion of the right ovarian vein into the vena cava, inferior mesenteric artery (IMA), bifurcation of the aorta, bifurcation of the common iliacs (bilateral), and the insertion of the deep circumflex vein (DCV) in to the external iliac vein (bilateral). Postoperatively, an abdominal X-ray was obtained. Comparisons were made between these eight major vascular landmarks and radiographic bony landmarks that are used to define radiation field boundaries. The percentage of vascular landmarks that were encompassed or fell outside of traditional radiation fields was determined with a 1-cm margin considered an adequate boundary for radiation. These measurements were also compared to patient BMIs.

RESULTS

Radiation fields defined by traditional bony landmarks would adequately encompass the paraaortic lymph nodes in the majority of patients (91%). For pelvic radiation fields, there was a significant "miss" (39%) of common iliac lymph nodes. Approximately one quarter (26%) of patients would receive inadequate coverage of one or both of the lateral boundaries of pelvic radiation. There was no apparent correlation of BMI to vascular or bony landmarks.

CONCLUSIONS

Radiation fields determined by traditional bony landmarks do not adequately reflect the anatomic (surgical) landmarks associated with the lymphatic drainage of the female reproductive organs. Although the majority of tertiary care centers now use advanced imaging techniques (e.g. computed tomography) to plan their radiation treatments, the historical guidelines of radiographic landmarks are still used in smaller institutions and continue to be referenced in Gynecologic Oncology Group protocols. For centers still using radiographic landmarks, the application of hemoclips with X-ray identification is a low-cost modality that is easily reproducible and may be clinically useful in guiding treatment.

Radiotherapy of malignant subdiaphragmatic implants in advanced ovarian carcinoma: a new technique

We report the development of a new technique using remote afterloading intraoperative radiation therapy to deliver a tumoricidal dose to diaphragmatic tumor implants. A multi-positional lucite applicator was designed based on anatomic studies of the diaphragmatic surface to accommodate a high dose rate iridium source in a series of needles placed 1.5 cm apart. The applicator curvature can vary from planar to full accommodation of the diaphragmatic surface with a constant source to surface distance of 0.5 cm. The applicator has been piloted in three patients with ovarian carcinoma with residual subdiaphragmatic disease found at second look laparotomy, to deliver a dose of 1,500 to 2,000 cGy at 0.5 cm. Tolerance of the diaphragm and hepatic surface has been excellent. There were no postoperative complications and no deterioration in liver function studies. The additional postoperative external beam irradiation directed with the aid of surgically placed clips and gated to respiratory movements permits achievement of a tumoricidal dose while limiting the treated volume and related toxicities.

A pilot study investigating intraoperative electron beam irradiation in the treatment of ovarian malignancies

Intraoperative electron beam radiation therapy (IOEBRT) in the treatment of ovarian malignancies was investigated at the Clement O. Miniger Radiation Oncology Center (COMROC). Nine patients were operated in the COMROC IOEBRT operating amphitheater and five were found to have disease sufficiently limited to allow for IOEBRT. The patients' ages ranged from 13 to 80 (median 53) years. Five patients had serous cystadenocarcinoma, one papillary adenocarcinoma, one mixed germ cell tumor, one squamous cell carcinoma, and one granular cell tumor of the ovary. The median survival of the non-IOEBRT group was 13 (range 12-29) months, while the IOEBRT group's median survival was 14 (range 18-46) months. All of the patients tolerated IOEBRT well without addition to the surgical morbidity.

Optimal coverage of peritoneal surface in whole abdominal radiation for ovarian neoplasms

Patterns of failure in ovarian carcinoma include early seeding of the entire peritoneal cavity. Inability to encompass the anatomic extent of the peritoneal cavity is a possible factor leading to relapse. However, little has been published regarding technical advances in optimal coverage of the peritoneal surface in whole abdominal radiation. In the Department of Radiation Oncology at the University of Michigan, 21 consecutive patients were analyzed prospectively in regard to adequate coverage of peritoneum in the treatment of advanced ovarian carcinoma. Simulation and focused blocks were designed to treat the whole abdomen. CT treatment planning studies were obtained with the entire peritoneum identified as the target volume. Simulator designed blocks were projected over the CT scans throughout the treatment volume. Dose volume histograms were used to calculate the amount of target volume missed for each treatment plan. All treatment plans demonstrated different degrees of volume miss, ranging from 1 cm3 to 837.3 cm3 with a median of 137.9 cm3 overall. Volume missed directly correlated with increasing patient weight and flatter pelvic shape, but poorly with AP separation. This was especially evident for patients requiring treatment at extended distances in both the supine and prone positions. We conclude that bony landmarks are poor guidelines in designing pelvic blocks, especially in heavy patients and patients requiring treatment in both prone and supine positions. CT treatment planning is helpful to ensure optimal peritoneal coverage.

Toxicity of open-field whole abdominal irradiation as primary postoperative treatment in gynecologic malignancy

Between June 1979 and March 1985, 77 patients received whole abdominal radiation as the sole postoperative treatment for gynecologic malignancy. With an open-field technique of irradiation, a median of 3,000 cGy was delivered to the entire abdominal contents with partial liver and kidney shielding; the total dose to the pelvis after boosts was 5,100 cGy, and that to the sub-diaphragmatic and para-aortic nodal regions was 4,200 cGy. The primary sites of malignancy were the endometrium in 41 patients, ovary in 25, uterus in 5, fallopian tube in 4, and cervix in 2. Seven patients (9%), all older than 60 years, experienced acute gastrointestinal toxicity that interrupted treatment, only one of whom failed to complete the prescribed course as a result. Hematologic toxicity was sufficient to interrupt therapy in 21 patients (27%), 1 of whom failed to complete therapy as a result. Hematologic toxicity was not increased in elderly patients. All patients were followed up for a minimum of 30 months (median, 43 months) or until death. Six patients experienced a treatment-related bowel obstruction (two of whom had concomitant progressive intra-abdominal disease); the 3-year actuarial risk for a treatment-related bowel obstruction was 9%. This risk was significantly increased by high-dose boosting for residual disease. Only one instance of clinical radiation pneumonitis occurred, and no cases of clinical hepatitis were noted; however, subclinical evidence of pulmonary and hepatic radiation effect was frequent. Whole abdominal irradiation as described has modest toxicity for patients with gynecologic cancer who are at high risk for intra-abdominal failure.

Fallopian tube cancer: the role of radiation therapy

Thirty-four patients with fallopian tube cancer were evaluated at the Mayo Clinic between 1964 and 1985 and received radiation therapy postoperatively. Employing a system analogous to FIGO ovarian cancer staging, there were 9 patients with stage I disease, 13 with stage II, and 12 with stage III/IV. Residual disease was present in 15 patients and absent in 19. Nodal metastases were documented in 12 patients or 35% (10 at presentation, two at relapse), with para-aortic nodes most commonly involved (67%) and 7 of the 12 having disease otherwise limited to the pelvis at presentation. Fifteen of 34 (44%) patients survived disease-free until intercurrent death or to a median follow-up of 70 months. Seven patients were treated with palliative intent for massive disease, and 27 patients were treated with curative intent (21 radiation alone, six radiation plus chemotherapy). Of those treated with curative intent, 15 patients received pelvic irradiation (with or without para-aortic nodal irradiation), 10 received whole abdominal irradiation, and 2 received intraperitoneal radiophosphorus. In the potentially curative group, seven of nine (78%) patients with stage I disease, five of 12 (42%) with stage II, and 2 of 6 (33%) with stage III have remained disease-free. Among the 21 patients with stage I or II disease, only four of the 11 (36%) patients who received pelvic irradiation alone were disease-free, but four patients had an isolated upper abdominal failure. In contrast, eight of 10 (80%) patients receiving treatment to the entire abdomen (including two patients who received 32P) were disease-free.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic factors in borderline and invasive ovarian tumors of the common epithelial type

Present reports show that surgical factors, response to therapy and histological criteria are important for predicting the prognosis of patients with common epithelial types of ovarian tumors. Newer techniques such as morphometry, DNA cytometry, immunological and immunopathological techniques may help to define prognostic factors even more accurately. As a result, these recently developed methods may enhance the value of well-established classical predictors of the outcome in case of borderline or invasive ovarian tumour.

Combined modality treatment for stage III ovarian carcinoma

Thirty-eight Stage III ovarian carcinoma patients were treated with a combined modality protocol consisting of sequential initial surgery with a maximal tumor reduction, CHAD combination chemotherapy, second look reductive surgery and whole abdominal irradiation. Sixteen patients (42%) had minimal residual tumors (less than 2 cm) after initial surgery (Stage IIIA) and 22 (58%) had large residual tumors (greater than 2 cm) (Stage IIIB). The patients received 3-14 courses of CHAD combination chemotherapy, with a response rate (CR + PR) in the evaluable (Stage IIIB) patients of 91%. Twenty-eight patients had a second attempt of cytoreductive operation (10 Stage IIIA patients and 18 Stage IIIB patients). In 10 patients no residual tumor was found. In another 12 patients residual tumor (less than 2 cm) was found and completely resected, whereas in six patients a complete resection of large residual tumors (greater than 2 cm) was not possible. Twenty-one of the patients also completed a course of whole abdominal radiotherapy. Radiation was well-tolerated with the usual expected amounts of nausea, vomiting, diarrhea and transient leukopenia and thrombocytopenia. 11/21 (52%) of the patients relapsed within the first 18 months after completion of radiotherapy. The actuarial relapse-free survival at 36 months from completions of radiotherapy was 44%. The actuarial survival for the whole group from diagnosis was 43% at 3 years (70% for Stage IIIA and 41% for Stage IIIB). The data indicated that this combined modality protocol is both feasible and well-tolerated but its curative potential for patients with advanced ovarian carcinoma is as yet unknown.