Integrating radiation therapy in the curative management of ovarian cancer: current issues and future directions

Role of salvage radiotherapy for recurrent ovarian cancer

OBJECTIVE

This study aimed to report clinical outcomes of salvage radiotherapy for recurrent ovarian cancer and identify predictors of clinical outcomes.

METHODS

We retrospectively reviewed data of patients who received salvage radiotherapy for recurrent ovarian cancer between January 2011 and June 2021. Stereotactic body radiotherapy, involved-field radiotherapy with conventional fractionation, and non-involved-field radiotherapy with conventional fractionation were included in this study. Local failure-free survival, progression-free survival, chemotherapy-free survival, and overall survival were assessed. Additionally, potential prognostic factors for survival were analyzed.

RESULTS

A total of 79 patients were included with 114 recurrent lesions. The median follow-up was 18.3 months (range 1.7-83). The 2-year local failure-free survival, progression-free survival, chemotherapy-free survival, and overall survival rates were 80.7%, 10.6%, 21.2%, and 74.7%, respectively. Pre-radiotherapy platinum resistance (hazard ratio (HR) 3.326, p<0.001) and short pre-radiotherapy CA-125 doubling time (HR 3.664, p<0.001) were associated with poor chemotherapy-free survival. The 1-year chemotherapy-free survival rates of patients with both risk factors, a single risk factor, and no risk factor were 0%, 20.4%, and 53.5%, respectively. The difference between risk groups was statistically significant: low risk versus intermediate risk (p<0.001) and intermediate risk versus high risk (p<0.001).

CONCLUSIONS

Salvage radiotherapy for recurrent ovarian cancer resulted in local control with improved chemotherapy-free survival in carefully selected patients. Our results suggest that the consideration of pre-radiotherapy platinum resistance and pre-radiotherapy CA-125 doubling time could help with patient selection.

The Significance of Radiotherapy in Ovarian Clear Cell Carcinoma: A Systematic Review and Meta-Analysis

OBJECTIVE

To assess the response rate and survival effect of adjuvant radiotherapy (RT) or chemoradiotherapy (CRT) during ovarian clear cell carcinoma (OCCC).

METHODS

We searched Web of Science, PubMed, Cochrane library electronic databases, Clinical Trials, WanFang Data and Chinese National Knowledge Infrastructure (CNKI) up to October 2022. We also searched registers of clinical trials, abstracts of scientific meetings and reference lists of included studies.

RESULTS

We identified a total of 4259 patients from 14 studies met the inclusion criteria. The pooled response rate of residual tumors for RT/CRT was 80.0%, the pooled 5-year progression-free survival (PFS) ratio during RT/CRT group was 61.0%, and the pooled 5-year overall survival (OS) ratio during RT/CRT group was 68.0%; heterogeneity tests demonstrated significant difference between studies (I² >50%). Cumulative results suggested adjuvant RT/CRT improved 5-year PFS ratio of OCCC patients (OR: 0.51 (95% CI: 0.42-.88), I² = 22%, P = .009), had no impact on 5-year OS ratio (OR: 0.52 (95% CI: 0.19-1.44), I² = 87%, P = .21); meta-regression of studies before and after 2000 found consistent results. Sub-analysis observed that adjuvant RT/CRT had no impact on 5-year OS ratio of early-stage (stage I + II) OCCC patients (OR: 0.67 (95% CI: 0.25-1.83), I² = 85%, P = .44), but might improve 5-year OS ratio of advanced and recurrent OCCC patients (OR: 0.13(95% CI: 0.04-.44), P = .001).

CONCLUSION

This analysis suggested that adjuvant RT/CRT might improve oncologic outcomes of OCCC, especially for advanced and recurrent cases. Due to the inherent selective biases of retrospective studies enrolled in the meta-analysis, more convincing evidences based on prospective randomized controlled trials (RCTs) are urgently needed.

Involved-field radiation therapy for selected cases of recurrent ovarian cancer

OBJECTIVES

In our institutional experience, involved-field radiation therapy (IFRT) yields favorable outcomes in patients with recurrent epithelial ovarian cancer (EOC). This retrospective study aimed to investigate the clinical benefits of IFRT in this patient population.

METHODS

Among patients treated with IFRT for recurrent EOC between 2010 and 2017, 61 patients with 90 treatments were included. IFRT encompassed all treatable lesions identified via imaging studies with 10-15-mm margins. Prescribed doses were ≥45 Gy (equivalent dose in 2 Gy/fraction).

RESULTS

Patients were followed up for a median of 19.0 (Interquartile range, 8.6-34.9) months after IFRT. The 2-year in-field control, progression-free survival, and overall survival (OS) rates were 42.7%, 24.2%, and 78.9%, respectively. Fifty-three IFRT sessions (58.9%) were followed by systemic chemotherapy, and the median chemotherapy-free interval (CFI) was 10.5 (95% confidence interval=7.3-13.7) months. A higher carbohydrate antigen-125 (CA-125) level correlated with a worse 2-year OS (69.2% vs. 91.0%; p=0.001) and shorter median CFI (4.7 vs. 11.9 months; p<0.001). Twenty-eight (31.1%) of 90 treatments yielded a long-term CFI >12 months. For patients with a normal CA-125 level and/or platinum-sensitive tumor, IFRT prolonged CFI regardless of pre-existing carcinomatosis, gross tumor volume, and number of treatment sites.

CONCLUSION

Our early experience demonstrates the safety and feasibility of IFRT as an effective salvage therapy and enables a "chemotherapy holiday" in selected recurrent EOC settings. The CA-125 value before IFRT (within normal range) and/or platinum sensitivity could be used as selection criteria for IFRT.

Treatment-interval associated effect of irradiation on locoregionally-relapsed ovarian cancer

Recurrent ovarian cancer following chemotherapy is usually incurable, particularly when the tumor acquires a drug resistance. The present study aimed to define the effect of irradiation on locoregional recurrences and the impact of the factors on the efficacy. The study retrospectively reviewed the clinical records of 61 patients with epithelial ovarian cancer who received irradiation following repeated chemotherapy between 1997 and 2006. A positive-irradiation response was designated as complete response, partial response, minor response or no change (NC). Due to the possible synergistic effect of chemotherapy and irradiation, and the cross-resistance to chemotherapeutic drugs and radiation, the focus was on the treatment break between chemotherapy and radiation, and patients were classified into 3 categories: Category I, ≤1 month; II, 1-6 months; and III, >6 months. The effect of irradiation was analyzed in association with histology, treatment break, recurrent site, irradiation dose and chemosensitivity. The post-irradiation survival time was analyzed by the irradiation response and treatment category. The median biological-effective dose was 60.0 Gy (range, 15.6-72.0 Gy). The sites irradiated included nodal recurrence (36), abdominal (six) and pelvic cavity (five cases). Histologically, serous adenocarcinoma was the most common type of the disease (23 cases) compared to mucinous (four), endometrioid (three), and clear-cell types (six cases). The median survival times were 4.5 months in the radiation responders (13 cases) and 15.3 months in the non-responders (37) (P=0.004). The positive-irradiation response was significantly associated with the treatment break (P=0.026) and chemosensitivity (P=0.007). In conclusion, irradiation for recurrent ovarian cancer produced an improved survival benefit when applied to chemoresponsive, locoregional-recurrent tumors immediately following chemotherapy.

Involved-field radiation therapy for locoregionally recurrent ovarian cancer

OBJECTIVE

To evaluate the effectiveness of definitive involved-field radiation therapy (IFRT) for selected patients with locoregionally-recurrent ovarian cancer.

METHODS

We retrospectively reviewed records of 102 epithelial ovarian cancer patients treated with definitive IFRT (≥45Gy). IFRT was directed to localized nodal (49%) and extranodal (51%) recurrences.

RESULTS

The median time from diagnosis to IFRT was 36 months (range, 1-311), and the median follow-up after IFRT was 37 months (range, 1-123). Patients received a median of three chemotherapy courses before IFRT (range, 0-9). Five-year overall (OS) and progression-free survival (PFS) rates after IFRT were 40% and 24% respectively; the 5-year in-field disease control rate was 71%. Thirty-five patients (35%) had no evidence of disease at a median of 38 months after IFRT (range, 7-122), including 25 continuously without disease for a median of 61 months (range, 17-122) and 10 with salvage treatment following disease recurrence, disease-free for a median of 39 months after salvage treatment (range, 7-92). Eight clear cell carcinoma patients had higher 5-year OS (88% versus 37%; p=0.05) and PFS (75% versus 20%; p=0.01) rates than other patients. Patients sensitive to initial platinum chemotherapy had a higher 5-year OS rate than platinum-resistant patients (43% versus 27%, p=0.03). Patients who required chemotherapy for recurrence after IFRT often benefitted from longer chemotherapy-free intervals after than before IFRT.

CONCLUSIONS

Definitive IFRT can yield excellent local control, protracted disease-free intervals, and even cures in carefully selected patients. RT should be considered a tool in the curative management of locoregionally-recurrent ovarian cancer.

Risk stratification of abdominopelvic failure for FIGO stage III epithelial ovarian cancer patients: implications for adjuvant radiotherapy

Objective

To analyze patterns of abdominopelvic failures and to define subgroups for the use of adjuvant radiotherapy in the International Federation of Gynecology and Obstetrics (FIGO) stage III epithelial ovarian cancer (EOC).

Methods

We reviewed 149 patients treated with debulking surgery followed by intravenous taxane and platinum chemotherapy between 1999 and 2008. Patient characteristics, patterns of failure, abdominopelvic failure APF-free survival (APFFS) and overall survival (OS) were analyzed.

Results

The median age of the patients was 51 years. Thirty-two patients (21.5%) were found to have residuum >2 cm after surgery. The median pretreatment CA-125 was 604 and 54.4% of patients had a decline in CA-125 ≥90% between pretreatment and at postoperative 1 month. With a median follow-up of 50 months, 79 patients (53.0%) experienced abdominopelvic failure (APF). The 5-year APF-free survival rate was 41.1%. Lymph node metastasis, size of residual disease, and decline in CA-125 were found to be significant prognostic factors for APF upon multivariate analysis. The group of patients in whom abdominopelvic irradiation was indicated as definitive postoperative treatment comprised 55% of the overall patient population and their 5-year survival rate was 68%.

Conclusion

The stratification was suggested to predict APF based on lymph node metastasis, size of residual tumor, and decline in CA-125. Adjuvant radiotherapy covering the whole abdominopelvis using the intensity modulation technique may be considered to reduce APF in FIGO stage III EOC patients with intermediate risk.

Platinum-based adjuvant chemotherapy on moderate- and high-risk stage I and II epithelian ovarian cancer patients. Long-term single institution experience and literature review

BACKGROUND

Although the optimal management of women with FIGO stages I and II epithelial ovarian cancer (EOC) is still controversial, platinum-based adjuvant chemotherapy (CT) is the mainstay of treatment. Suboptimal survival results have led to major efforts to identify prognostic factors, improve surgical staging and develop adjuvant therapies to improve patients' outcomes.

PATIENTS AND METHODS

We evaluate in a retrospective study clinical efficacy and the toxicity profile of a platinum-based adjuvant CT in FIGO stages I and II EOC treated at our institution from March 1984 to December 2006. Grade I FIGO stages IA-IB were excluded from the analysis. In the first period (1984-1997), patients received a platinum-based regimen without taxanes. In the second period from 1997 onwards, patients were treated with carboplatin and paclitaxel. Four to six cycles of adjuvant CT were administered. Potential predictive factors of efficacy and the role of paclitaxel addition were also analysed.

RESULTS

One hundred and fifty-eight patients (60 treated with paclitaxel) met inclusion criteria and were evaluable. Median age at diagnosis was 53.7 years (range 19-81) and most patients had an Eastern Cooperative Oncology Group performance status score (ECOG) of 0-1 (91.8%); 82.9% patients had pathological stage I and 17.1% pathological stage II. With a median follow up of 8.34 years (range 4.4-11.6), 103 patients (74.1%) were free of disease and 110 of them were alive (79.1%). Median relapse-free survival (RFS) and median overall survival (OS) had not been reached at the time of the analysis. No survival difference was found between paclitaxel and carboplatin combination or non-paclitaxel-containing regimens. Statistically significant prognostic factors for better RFS in the multivariate analysis were: ECOG 0 (p=0.023; HR 0.32; 95% CI 0.17-0.57); FIGO I stage (p<0.001; HR 0.30; 95% CI 0.15-0.58); I-II histological grade (p=0.005; HR 0.38; 95% CI 0.19-0.75); mucinous histology (p=0.013; HR 0.28; 95% CI 0.13-0.53); non-surgical adherences (p<0.002, HR 0.32; 95% CI 0.15-0.54); paracolic gutters inspection (p=0.033; HR 0.50; 95% CI 0.26-0.95) and liver surface biopsies (p=0.048; HR 0.64; 95% CI 0.41-0.98).Toxicity was generally mild and non-haematologic events were the most commonly found (62.9% of the total). The most frequent haematologic toxicities were neutropenia (41.7% in all grades, 9.5% grade 3-4) and anaemia (29.1% in all grades, 3.2% grade 3-4).

CONCLUSIONS

The long-term outcome of this series is comparable to the published evidence and reflects the limited activity of platinum-based CT in the adjuvant setting. The potential survival advantage of the addition of paclitaxel to carboplatin cannot be definitively answered due to the small number of patients, the limited follow-up and the retrospective nature of the study. More effective and specific treatments are clearly required, in particular for those patients with stage II and undifferentiated tumours. Quality of surgery entails prognostic value.

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.

Long-term morbidity of adjuvant whole abdominal radiotherapy (WART) or chemotherapy for early stage ovarian cancer

The aim of the study was to evaluate long-term toxicity of adjuvant treatment in early stage ovarian cancer survivors. Data from all patients treated in one hospital for early stage ovarian cancer diagnosed between 1980 and 1990 were collected using a structured data form. In 93 FIGO stages I and II patients, cytoreductive and staging surgery was performed; 15 received no adjuvant treatment (controls), 39 whole abdominal radiotherapy (WART) and 39 platin-based chemotherapy. Median age at diagnosis was 54 years (range 21-83 years). During follow-up, 49/93 (53%) patients have died with a median overall survival of 18.4 years (95% CI 12.8-23.9). In both the radiotherapy and the chemotherapy group, 50% of patients reported long-term side-effects (all grades) versus 13% of controls. Two patients in the WART group died from bowel complications. Secondary malignancies were observed in 16 patients. Of all patients alive at the last follow-up, 12/17 (71%) patients treated with radiotherapy and 11/18 (61%) treated with chemotherapy experienced long-term morbidity versus 2/9 (22%) controls (P=0.03).

IN CONCLUSION

Long-term follow-up of early stage ovarian cancer patients showed lasting GI morbidity in the survivors treated with adjuvant radiotherapy, which has therefore become obsolete. Cisplatin-based chemotherapy caused peripheral neuropathy versus virtual absence of problems in the survivors of just surgery, emphasising the need for strict criteria before instigating adjuvant treatment.

Whole-abdomen, single-dose consolidation radiotherapy in patients with pathologically confirmed complete remission of advanced ovarian epithelial carcinoma: a long-term survival analysis

The value of consolidation therapy in advanced epithelial ovarian carcinoma patients is controversial. The aim of the present study was to assess the long-term survival of patients with a pathologically confirmed complete remission who had consolidation by single-dose, whole-abdominopelvic radiotherapy. Of 96 histologically confirmed stage II-IV epithelial ovarian carcinoma patients who underwent cytoreductive surgery followed by high-dose, platin-based chemotherapy, 57 were in complete clinical remission at the end of therapy and 50 underwent a second-look laparotomy. The study group comprises 32 consecutive patients who had no pathological evidence of disease and who received 800 cGy single-dose, whole-abdominal radiotherapy by an 8 MEV linear accelerator in a single fraction. The absolute 5-year survival and the actuarial 10-year survival were 78.7 and 63.3%, respectively. The survival was significantly better in patients who had < or =2 cm residual disease at the completion of the original operation. No severe postradiation complications were encountered. Mild complications were seen in three (9.4%) patients. Our data indicate a favorable long-term survival of patients with a negative second-look laparotomy who had consolidation with single-dose, whole-abdominal radiotherapy. These results seem to suggest that a collaborative, prospective, randomized multiarm study is indicated to solve the controversial issue of consolidation therapy.

High-dose whole abdominal and pelvic irradiation for treatment of ovarian carcinoma: long-term toxicity and outcomes

PURPOSE

To evaluate the role of high-dose whole abdominal and pelvic irradiation (WART) in the treatment of epithelial ovarian carcinoma.

METHODS AND MATERIALS

A retrospective review was performed on 71 patients with Stage I-III ovarian carcinoma who were treated with WART using an open field technique after total abdominal hysterectomy and bilateral oophorectomy with or without omentectomy. Whole abdominal doses greater than typically recommended were used in a series of patients to enhance local control and to decrease abdominal recurrence. None of the patients had received chemotherapy before RT. Thirty-one patients received Alkeran or cyclophosphamide and two received cisplatin-based chemotherapy after WART. The median whole abdominal dose was 36 Gy (range 9-45.5), delivered in a median of 30 fractions (range 8-46). A pelvic boost was delivered using AP-PA fields during whole abdominal RT to a total midline pelvic dose of 200 cGy/d. The median pelvic dose was 51 Gy (range 16-59). The right lobe and a portion of the left lobe of the liver were shielded with custom blocks at a median dose of 25 Gy (range 9-41). The kidneys were shielded either AP-PA or PA from the first day of RT. The median dose to the kidneys was 19 Gy (range 4-30).

RESULTS

The 5-year overall survival rate was 93%, 48%, and 29% for Stage I, II, and III patients, respectively. On multivariate analysis, stage and the extent of residual disease were independent prognostic factors. The 5- and 10-year overall survival rate for the 46 patients in the intermediate-risk group was 61% and 54%, respectively. For this group, a total abdominal dose of > or /=36 Gy was associated with a longer overall survival independent of stage, grade, and the amount of residual disease. This was most likely due to a significant reduction in the incidence of abdominal recurrence in patients receiving >36 Gy to the whole abdomen (18% vs. 49%, p = 0.006). Multivariate analysis revealed that grade (p = 0.023) and abdominal dose (p = 0.018) were independent factors influencing the rate of abdominal recurrence. Pelvic recurrence was rare as a first site of failure (6%). Twenty-one percent (n = 15) of the patients developed Grade 3 or 4 (Radiation Therapy Oncology Group [RTOG] criteria) chronic small or large bowel toxicity. Eleven percent of all patients had a small bowel obstruction requiring surgery. A whole abdominal dose >30 Gy and a pelvic dose >50 Gy were associated with a significant increase in small bowel obstruction (p = 0.01) independent of other factors. Chronic Grade 3 or 4 (Common Toxicity Criteria) anemia, thrombocytopenia, and leukopenia were seen in 7%, 1%, and 4% of the patients, respectively. Transient liver enzyme elevation was common (62%). Two patients had Grade 3 (RTOG) hepatic toxicity. Grade 3 or 4 renal toxicity (RTOG) was observed in 4%, and 2 patients (3%) were diagnosed with pelvic insufficiency fractures that were managed conservatively.

CONCLUSION

Survival after RT for ovarian carcinoma rivals that achieved with systemic chemotherapy. The results of this study suggest a possible dose-control relationship between the whole abdominal dose and the risk of abdominal recurrence; however, a higher rate of small bowel obstruction was observed when greater abdominal doses and greater pelvic doses were combined. Careful attention to balancing toxicity and efficacy is imperative if RT is to have a future role in the treatment of this disease.

IMRT of large fields: whole-abdomen irradiation

PURPOSE

To assess the feasibility of inverse planning for whole-abdomen intensity-modulated radiation therapy (IMRT) with bone marrow and kidney sparing and to develop approaches to circumventing field size restrictions in the application of whole-abdomen IMRT using dynamic multileaf collimators (DMLC).

METHODS AND MATERIALS

The entire peritoneal cavity as derived from serial computerized tomography scans was defined as the gross target volume, whereas the planning target volume (PTV) was defined as the gross target volume plus a 5-mm margin extending 1 cm superiorly and inferiorly. In 10 randomly selected patients, the PTV ranged from 5629 to 12578 cc (median 7935 cc), and the superior-inferior, lateral, and anterior-posterior dimensions of the PTV ranged from 37 to 46 cm (median 42.5 cm), 27 to 33 cm (median 29 cm), and 18 to 23 cm (median 20 cm), respectively. A single isocenter was defined for patients with field length <40 cm. For patients with fields >40 cm, two isocenters were defined: one in the abdominal region, and the other in the pelvis. For IMRT planning, five 15-MV intensity-modulated beams at gantry angles of 180 degrees, 105 degrees, 35 degrees, 325 degrees, and 255 degrees were used. Optimization was designed to spare kidneys and bones. To fully account for the significant scattered dose contributions, an iterative process for dose calculations was implemented in the optimization. To overcome the 15-cm field width limit of our DMLC delivery system, fields with a width >15 cm were split into two or more subfields. To minimize field match errors, adjacent subfields overlapped by at least 2 cm, with intensity "feathering" in the overlap region. For patients with two isocenters, fields were overlapped and feathered in the cephalad-caudad direction by at least 3 cm. For comparison, conventional anterior-posterior/posterior-anterior 6-MV photon beams with posterior kidney blocks at extended distance were also generated for each patient.

RESULTS

Treatment plan optimization calculations required 20-80 min on a 500-MHz DEC alpha workstation. Including beam splitting, an average of 16 DMLC beams was used per patient. Delivery of 150 cGy required, on average, 1442 monitor units. For the same dose constraints on the kidneys, whole-abdomen IMRT resulted in significant dose reduction to the bones and improved PTV coverage as compared to conventional treatment. For a prescription dose of 30 Gy, the volume of the pelvic bones receiving more than 21 Gy was reduced on average by almost 60% with IMRT, and the mean dose to all bones was reduced from 24.0 +/- 1.5 Gy to 18.5 +/- 1.0 Gy (p = 0.002). PTV coverage, as measured by V95 (the volume receiving 95% of the prescription dose), improved from 71.7 +/- 4.8% with conventional treatment to 83.5 +/- 3.9% with IMRT (p = 0.002), although small regions of underdose in areas near the kidneys could not be avoided completely. The high-dose regions within the PTV, as measured by D05 (the dose covering 5% of PTV volume), increased slightly from 31.2 +/- 0.6 Gy with conventional treatment to 32.8 +/- 0.2 Gy with IMRT.

CONCLUSION

We have developed a process to plan and deliver whole-abdomen IMRT using standard linear accelerators and DMLC. IMRT can achieve better PTV coverage with the same level of kidney sparing and improved sparing of the bone marrow. These methods may be applicable also to other sites requiring large-field irradiation.

Antiangiogenic and antitumor effects of a protein kinase Cbeta inhibitor in human breast cancer and ovarian cancer xenografts

In cell culture, the compound 317615 2HCl, a potent inhibitor of VEGF-stimulated HUVEC proliferation, was not very effective against MX-1 breast cancer cells (IC50= 8.1 microM) or SKOV-3 ovarian carcinoma cells (IC50 = 9.5 microM). Exposure to combinations of paclitaxel or carboplatin and 317615 x 2HCl with MX-1 cells in culture resulted in cell survival that reflected primarily additivity of the two agents. Exposure of SKOV-3 cells to paclitaxel or carboplatin along with 317615 2HCl resulted in cell survivals that reflected additivity of 317615 x 2HCl with paclitaxel and greater-than-additive cytotoxicity with carboplatin. Administration of 317615 x 2HCI orally twice daily to nude mice bearing subcutaneous MX-1 tumors or SKOV-3 tumors resulted in a decreased number of intratumoral vessels as determined by CD31 and CD105 staining with decreases of 35% and 43% in MX-1 tumors and 60% and 75% in SKOV-3 tumors, respectively. 317615 x 2HCl was an active antitumor agent against the MX-1 xenograft and increased the tumor growth delay produced by paclitaxel by 1.7-fold and the tumor growth delay produced by carboplatin by 3.8-fold. Administration of 317615 x 2HCl also increased the tumor growth delay produced by fractionated radiation therapy in the MX-1 tumor. Treatment with 317615 x 2HCl alone increased the lifespan of animals bearing intraperitoneal SKOV-3 xenografts by 1.9 fold compared with untreated control animals. The combination of paclitaxel and 317615 x 2HCl resulted in 100% 120-day survival of SKOV-3 bearing animals. Administration of 317615 x 2HCl along with carboplatin to animals bearing the SKOV-3 tumor produced a 1.8-fold increase in lifespan compared with carboplatin alone. 317615 x 2HCl is a promising new antiangiogenic agent that is in early phase clinical testing.

Intensity-modulated radiotherapy

Intensity-modulated radiotherapy represents a recent advancement in conformal radiotherapy. It employs specialized computer-driven technology to generate dose distributions that conform to tumor targets with extremely high precision. Treatment planning is based on inverse planning algorithms and iterative computer-driven optimization to generate treatment fields with varying intensities across the beam section. Combinations of intensity-modulated fields produce custom-tailored conformal dose distributions around the tumor, with steep dose gradients at the transition to adjacent normal tissues. Thus far, data have demonstrated improved precision of tumor targeting in carcinomas of the prostate, head and neck, thyroid, breast, and lung, as well as in gynecologic, brain, and paraspinal tumors and soft tissue sarcomas. In prostate cancer, intensity-modulated radiotherapy has resulted in reduced rectal toxicity and has permitted tumor dose escalation to previously unattainable levels. This experience indicates that intensity-modulated radiotherapy represents a significant advancement in the ability to deliver the high radiation doses that appear to be required to improve the local cure of several types of tumors. The integration of new methods of biologically based imaging into treatment planning is being explored to identify tumor foci with phenotypic expressions of radiation resistance, which would likely require high-dose treatments. Intensity-modulated radiotherapy provides an approach for differential dose painting to selectively increase the dose to specific tumor-bearing regions. The implementation of biologic evaluation of tumor sensitivity, in addition to methods that improve target delineation and dose delivery, represents a new dimension in intensity-modulated radiotherapy research.

Effective palliative radiation therapy in advanced and recurrent ovarian carcinoma

PURPOSE

To retrospectively review our experience using radiation therapy as a palliative treatment in ovarian carcinoma.

METHODS AND MATERIALS

Eighty patients who received radiation therapy for ovarian carcinoma between 1983 and 1998 were reviewed. The indications for radiation therapy, radiation therapy techniques, details, tolerance, and response were recorded. A complete response required complete resolution of the patient's symptoms, radiographic findings, palpable mass, or CA-125 level. A partial response required at least 50% resolution of these parameters. The actuarial survival rates from initial diagnosis and from the completion of radiation therapy were calculated.

RESULTS

The median age of the patients was 67 years (range 26 to 90 years). A median of one laparotomy was performed before irradiation. Zero to 20 cycles of a platinum-based chemotherapy regimen were delivered before irradiation (median = 6 cycles). The reasons for palliative treatment were: pain (n = 22), mass (n = 23), obstruction of ureter, rectum, esophagus, or stomach (n = 12), a positive second-look laparotomy (n = 9), ascites (n = 8), vaginal bleeding (n = 6), rectal bleeding (n = 1), lymphedema (n = 3), skin involvement (n = 1), or brain metastases with symptoms (n = 11). Some patients received treatment for more than one indication. Treatment was directed to the abdomen or pelvis in 64 patients, to the brain in 11, and to other sites in 5. The overall response rate was 73%. Twenty-eight percent of the patients experienced a complete response of their symptoms, palpable mass, and/or CA-125 level. Forty-five percent had a partial response. Only 11% suffered progressive disease during therapy that required discontinuation of the treatment. Sixteen percent had stable disease. The duration of the responses and stable disease lasted until death except in 10 patients who experienced recurrence of their symptoms between 1 and 21 months (median = 9 months). The 1-, 2-, 3-, and 5-year actuarial survival rates from diagnosis were 89%, 73%, 42%, and 33%, respectively. The survival rates calculated from the completion of radiotherapy were 39%, 27%, 13%, and 10%, respectively. Five percent of patients experienced Grade 3 diarrhea, vomiting, myelosuppression, or fatigue. Fourteen percent of patients experienced Grade 1 or 2 diarrhea, 19% experienced Grade 1 or 2 nausea and vomiting, and 11% had Grade 1 or 2 myelosuppression.

CONCLUSIONS

In this series of radiation therapy for advanced ovarian carcinoma, the response, survival, and tolerance rates compare favorably to those reported for current second- and third-line chemotherapy regimens. Cooperative groups should consider evaluating prospectively the use of radiation therapy before nonplatinum and/or nonpaclitaxel chemotherapy in these patients.

[Results of a randomized prospective trial comparing postoperative abdominopelvic radiotherapy with postoperative chemotherapy in early ovarian cancer]

PURPOSE

In a prospective randomized trial, our aim was to evaluate and compare the tolerance and efficacy of postoperative radiotherapy and chemotherapy in the treatment of early ovarian cancer.

MATERIAL AND METHODS

Between 1990 and 1996, 150 patients with ovarian cancer stage IA, IB grades G2-3, and all patients classified IC and IIA, who did not have evidence of residual disease after surgery, were randomized to two treatment branches: radiotherapy or chemotherapy (CH). In the radiotherapy branch (76 patients), a whole abdomen irradiation of 30 Gy in 24 fractions over 5 weeks, with a pelvic boost to 50 Gy, was delivered. In the chemotherapy branch (74 patients), there were six series of polychemotherapy separated with 3-weeks interval. In each series patients received association of cisplatin (50 mg/m2, d1), adriamycin (50 mg/m2, d1) and cyclophosphamide (500 mg/m2, d1).

RESULTS

The tolerance of the treatment was good and comparable in both groups. In the radiotherapy branch, three late grade G3 intestinal complications were observed (three bowel obstructions, which required surgery in two cases). The actuarial survival rate without evidence of disease was 81% at 5 years for both groups. In our series we found that histological grade had the strongest influence on survival prognosis; it was the only significant factor in a multivariate analysis. Patients with grade G3 tumors had the worst survival.

CONCLUSION

These data suggest that efficacy of postoperative radiotherapy and chemotherapy administered to our patients with early ovarian cancer gave approximately identical results.