Feasibility of concurrent cisplatin and extended field radiation therapy (EFRT) using intensity-modulated radiotherapy (IMRT) for carcinoma of the cervix

Less than whole uterus irradiation for patients with locally advanced cervical cancer

INTRODUCTION

Current consensus guidelines for definitive cervical cancer intensity modulated radiation therapy (IMRT) recommend inclusion of the entire uterus within the clinical target volume, however this is debated. We aimed to evaluate outcomes of patients with cervical cancer who were treated with less than whole uterus irradiation.

METHODS

We identified 109 patients with FIGO Stage IB-IVA cervical cancer treated definitively with concurrent chemoradiation, including IMRT and brachytherapy, from 2010 to 2022 at a single institution where the practice was to include the gross cervix tumor with an internal target volume with differences in bladder filing accounted for, plus additional 5 mm planning target volume (PTV) margin. Local, regional, and distant recurrences were analyzed using competing risk methods, and a Wilcoxon rank sum test was performed to assess differences in dose to organs at risk based on the proportion of the uterus included in the PTV, with the median proportion of the uterus included (75 %) used as the cut-point.

RESULTS

The median follow-up time was 65 months (range 3-352 months). The 2-year cumulative incidence of LR for the entire cohort was 4.2 % (95 % confidence interval [CI] 1.3-9.7). Compared with patients who had ≥ 75 % of the uterus included in the PTV, patients who had < 75 % of the uterus included in the PTV had significantly lower bowel D200cc (p = 0.02). The cumulative incidence of local failure (LR) was not significantly different between the two groups.

CONCLUSIONS

Including less than the whole uterus for definitive cervix cancer IMRT does not seem to compromise local control. Less than whole uterus irradiation could be considered for carefully selected cervix cancer patients to decrease bowel dose and possible treatment-related toxicity.

Improved Dosimetry with Daily Online Adaptive Radiotherapy for Cervical Cancer: Waltzing the Pear

AIMS

Standard of care radiotherapy for locally advanced cervical cancer includes large margins to ensure the uterocervix remains within the treatment fields over the course of treatment. Daily online cone-beam adaptive radiotherapy corrects for interfractional changes by adjusting the plan to match the target position during each treatment session, thus allowing for significantly reduced clinical target volume (CTV) to planning target volume (PTV) margins. We hypothesise that reduced margins from daily online adaptive radiotherapy will reduce organ at risk dose without compromising target coverage.

MATERIALS AND METHODS

Ten patients with cervical cancer (stage IIB-IIIC2) were treated with definitive chemoradiation using daily online cone-beam adaptive radiotherapy in 25-27 fractions. Initial and all adapted treatment plans were generated with CTV to PTV margins versus standard of care image-guided radiotherapy (IGRT) plans as follows: cervix/uterus/gross tumour volume (0.5 versus 1.5 cm), parametria/vagina (0.5 versus 1.0 cm) and nodal chains and gross nodes (0.5 versus 0.5 cm). IGRT plans were created and copied to synthetic computed tomography scans and contours generated from each daily adapted fraction. The dosimetry of each clinically treated online adapted fraction was compared with emulated IGRT plans. Statistical significance was defined as P < 0.05.

RESULTS

Daily online cone-beam adaptive radiotherapy significantly improves bowel bag dosimetry compared with IGRT, with a reduction in V40 by an average of 91.3 cm3 [V40 (-6.2%) and V45 (-6.1%)]. The daily adapted plans showed significant improvements in bladder and rectum [V40 (-25.2% and -36.0%) and V30 (-9.7% and -17.1%), respectively]. Additionally, bone marrow had a significantly reduced dose [V10 (-2.7%) and V20 (-3.3%)]. Daily online cone-beam adaptive radiotherapy improved uterocervix CTV coverage and reduced hotspots compared with IGRT [D95% (+1.6%) and Dmax (-0.9%)].

CONCLUSIONS

Reduced CTV to PTV margins achievable with daily online adaptive radiotherapy improves organ at risk dosimetry and target coverage when compared with standard of care IGRT for locally advanced cervical cancer. The clinical impact of improved dosimetry is currently undergoing investigation.

Prophylactic extended-field irradiation for locally advanced cervical cancer

Concomitant chemoradiotherapy is the standard treatment for locally advanced cervical cancer. Pelvic irradiation is commonly recommended for patients with negative para-aortic lymph nodes(PALNs). However, owing to the development of imaging-guided brachytherapy, distant failure has become the main failure pattern. The PALNs are a vital site of distant metastasis, and the para-aortic region may contain occult microscopic metastases that are barely detected owing to imaging technology restriction. The prognostic of patients who experienced PALN failure is dismal. Typically, there are four ways to decrease PALN failure. First, surgical staging can be performed to assess the occurrence of metastasis in the para-aortic region; however, the application of surgical staging is decreasing owing to controversial survival benefits and accompanying complications of surgery. Second, regular imaging surveillance and timely salvage of early recurrences could reduce PALN failure. Third, better systemic adjuvant therapy could be recommended since it has enormous potential to reduce distant metastases and improve overall survival. Fourth, performing prophylactic extended-field irradiation (EFI), including pelvic and para-aortic region irradiation, can sterilize occult microscopic metastases in the para-aortic region and improve survival. Prior investigations have revealed that prophylactic EFI could reduce PALN failure as well as distant metastasis and present the benefit of survival. Yet, owing to the serious morbidity induced by enlarged irradiation field in the era of conventional irradiation techniques, further research on EFI is stagnated. Nowadays, with the development of new technologies, intensity modulated radiation therapy can deliver a higher dose to tumors with acceptable toxicity. Prophylactic EFI regained attention. However, the inclusion criteria of prophylactic EFI in existing studies reveal great discrepancies. Thus, it is urgent to precisely identify indications for better survival and lower complications in patients with cervical cancer. In this review, we identify indications and summary guidelines for prophylactic EFI, which may provide a foundation for further trials and clinical applications.

Intensity modulated radiotherapy in carcinoma cervix with metastatic para-aortic nodes: an institutional experience from a Regional Cancer Centre of Eastern India

Background

Cervical cancer is a major health problem, especially in developing countries like India. Extended field radiotherapy (EFRT) for cancer cervix treatment remains a challenging task for radiation oncologists. In the last decade studies have shown that EFRT using intensity modulated radiotherapy (IMRT) is feasible in treating gynaecological malignancies but there is a dearth of literature on this specific topic from this part of the world where patient profile differs greatly in several aspects from that of the western world. The aim of the study was evaluation of treatment response and toxicity profile in cases of carcinoma cervix with metastatic para-aortic nodes treated with intensity modulated radiotherapy technique.

Materials and methods

In this retrospective study the treatment records of 45 para-aortic node positive cervical cancer patients treated with EFRT (IMRT) and concurrent cisplatin were analysed for evaluation of loco-regional control and toxicities.

Results

Forty-four patients received full course of treatment. Among those 44 patients, 93.2% achieved complete response. Overall, the treatment was tolerated well and toxicities were within acceptable limits. Acute grade 3–4 toxicities were observed mostly in the form of anaemia and leucopenia. Most common late toxicities were those of small and large intestine.

Conclusion

EFRT with concurrent chemotherapy was successfully delivered for para-aortic nodes positive cervical cancer patients in Indian scenario where under-nutrition, infection, anaemia and several other factors adversely influence treatment outcome. Pelvic and para-aortic control rates were satisfactory. The technique was associated with an acceptable acute and late toxicity profile.

Prospective observational study evaluating acute and delayed treatment related toxicities of prophylactic extended field volumetric modulated arc therapy with concurrent cisplatin in cervical cancer patients with pelvic lymph node metastasis

PURPOSE

To evaluate the treatment related acute and delayed toxicities of extended field Volumetric modulated arc therapy (VMAT) with concurrent chemotherapy in patients of locally advanced cervical cancer with pelvic lymph nodes.

MATERIAL AND METHODS

From 2014 to 2016, 15 patients of locally advanced cervical cancer with Fluoro-deoxyglucose positron emission tomography (FDG-PET) positive pelvic lymph nodes were treated with extended field Simultaneous integrated boost (SIB)-VMAT 45 Gy/55 Gy/25#/5weeks and concurrent cisplatin. Acute toxicities were documented according to common terminology criteria for adverse events version 4 (CTCAE v.4). Dose volume parameters and patient characteristics were analyzed for association with toxicities.

RESULTS

Median age of patients at diagnosis was 48 years. 40% (6 patients) were stage IIB & 60% (9 patients) were stage IIIB. Median number of involved pelvic lymph nodes was 2 (range, 1-4), commonest location was external iliac lymph node region (86%). Median number of concurrent chemotherapy cycles received was five. Treatment was well tolerated and there were no grade ≥ 3 acute toxicities. Commonest acute toxicities observed were vomiting (≥grade2 -13.3%) followed by & nausea (grade ≥ 2 in 6%) and were associated with volume of bowel bag receiving 45 Gy. Constitutional symptoms (≥grade 2) were observed in 6% patients and had no dosimetric associations. At a median follow up of 43 months, delayed ≥ grade1, 2, 3 toxicity were observed in 80%, 0%, and 0% respectively with diarrhea being the commonest.

CONCLUSION

Prophylactic para aortic extended field VMAT with concurrent chemotherapy for locally advanced cervical cancer is well tolerated with acceptable acute toxicity profile. Significant grade 3 acute/delayed toxicities were not observed in this cohort of patients.

Dosimetric predictors of nephrotoxicity in patients receiving extended-field radiation therapy for gynecologic cancer

Purpose

We sought dosimetric predictors of a decreasing estimated glomerular filtration rate (eGFR) in gynecological oncology patients receiving extended-field radiation therapy (EFRT).

Materials and methods

Between July 2012 and April 2020, 98 consecutive cervical or endometrial cancer patients underwent EFRT or whole-pelvis radiation therapy (WPRT) with concurrent cisplatin chemotherapy in our institution. To explore the effect of concurrent cisplatin chemotherapy on renal function, the renal function of the WPRT patients was examined. Of the 98 patients, 34 cervical or endometrial cancer patients underwent EFRT including extended-field intensity-modulated radiation therapy (EF-IMRT) and 64 cervical cancer patients underwent WPRT with cisplatin. Of the 34 EFRT patients, 32 underwent concurrent cisplatin chemotherapy. Excluding patients exhibiting recurrences within 6 months, 31 EFRT patients were analyzed in terms of the dose-volume kidney histograms (the percentages of kidney volumes receiving 12, 16, 20, and 24 Gy) and the post- to pre-treatment eGFR ratios. We calculated Pearson correlation coefficients between the renal dose volume and the percentage eGFR reductions of the 31 EFRT patients, and those treated via EF-IMRT. Renal dose constraint significance was evaluated using the Mann–Whitney U test.

Results

The eGFR value after WPRT with cisplatin remained largely unchanged for 12 months, unlike that after EFRT. In EFRT patients, a strong correlation was evident between the KV_20Gy dose and the post- to pre-treatment eGFR ratio (correlation coefficients − 0.80 for all patients and − 0.74 for EF-IMRT patients). In EF-IMRT patients, the kidney volume receiving 20 Gy tended to correlate negatively with the eGFR reduction. The Mann–Whitney U test showed that patients with KV_20Gy values < 10% retained significantly better renal function than did patients with KV_20Gy values > 10% (P = 0.002).

Conclusions

Imposition of a severe kidney dose constraint during EF-IMRT may reduce nephrotic toxicity. Future prospective investigations of kidney-sparing EF-IMRT are required.

Early toxicity and treatment outcomes of extended field-intensity modulated radiotherapy for cervical cancer patients with para-aortic nodal metastasis

Objective

Extended-field radiotherapy (EFRT) with concurrent chemotherapy represents standard treatment in cervical cancer patients with para-aortic lymph nodal (PALN) metastasis. While EFRT with Intensity Modulated RT (IMRT) has been demonstrated to reduce toxicities, the dose thresholds for minimizing acute toxicity is not clear. The present study was undertaken to report the early toxicity with extended-field intensity-modulated radiotherapy (EF-IMRT) for carcinoma of the cervix in our cohort of patients and determine dose-volume parameters that predict ≥grade II haematological toxicity and diarrhoea.

Methodology

This was a retrospective study of consecutive cervical cancer patients with PALN metastasis treated with EF-IMRT. Patients received rotational IMRT +/- neoadjuvant chemotherapy (NACT) and/or concurrent chemotherapy (45–50 Gy/25#/5 weeks) followed by high-dose rate brachytherapy. Acute haematological and gastrointestinal toxicity (diarrhoea and vomiting) was correlated with doses received by bowel and marrow. Receiver operator characteristics curves were used for deriving thresholds that predict for increased toxicity and tested on univariate and multivariate analysis. Finally, disease free and overall survival (DFS and OS) was calculated.

Results

A total of 43 patients were included. One-fourth of the patients (11/43) received NACT and 88% received concurrent chemotherapy. Within the upfront EF-IMRT cohort, 22.6% and 9.7% patients developed grade ≥III haematological (HT) and gastrointestinal (GI) toxicity respectively, with an increase in HT (≥ grade III HT =67%) in patients receiving NACT (p = 0.007). In the entire cohort bone marrow Volume receiving 10 Gy (V10>) 90% correlated with an increase in ≥ grade III HT (p = 0.05). No dose volume thresholds could be validated for GI toxicity. The OS and DFS at 2 years was 56% and 54%, respectively.

Conclusion

EF-IMRT is a feasible option for cervical cancer patients with PALN involvement and is associated with acceptable grade III toxicity. Future studies need to focus on minimizing HT toxicity.

Clinical outcome of extended-field irradiation vs. pelvic irradiation using intensity-modulated radiotherapy for cervical cancer

The aim of the present study was to evaluate the distinctions in survival and toxicity between patients with cervical cancer with common iliac node or para-aortic node involvement, who were treated with extended-field intensity-modulated radiotherapy (EF-IMRT) and patients with or without lower involved pelvic nodes, who were treated with pelvic IMRT. A total of 55 patients treated with EF-IMRT and 52 patients treated with pelvic IMRT at the Sun Yat-Sen University Cancer Center (Guangzhou, China) were retrospectively analyzed. Patients treated with EF-IMRT had the highest level of lymph node involvement to the para-aortic or common iliac nodes, while patients treated with pelvic IMRT had no para-aortic or common iliac nodes involved (P<0.001). The median follow-up time was 29.5 months. The 3-year overall survival (OS) rates of EF-IMRT and pelvic IMRT were 79.4 and 82.3% (P=0.45), respectively, and the 3-year disease-free survival (DFS) rates of EF-IMRT and pelvic IMRT were 61.0 and 73.7% (P=0.55), respectively. Cox's regression analysis revealed that EF irradiation was a protective prognostic factor for OS and DFS. A total of 16 patients in the EF-IMRT group and 13 patients in the pelvic IMRT group experienced treatment failure (P=0.67), with the patterns of failure being the same for the two groups (P=0.88). The cumulative incidence of grade 3 and 4 acute toxicities in the EF-IMRT group was 34.5%, in comparison with 19.2% in the pelvic group (P=0.048). The results of the present study suggest that patients with cervical cancer with grossly involved common iliac or para-aortic nodes should be electively subjected to EF irradiation to improve the survival and alter patterns of recurrence. Notably, EF irradiation delivered via IMRT exhibits an increased toxicity incidence, however, this remains within an acceptable range.

Prophylactic extended-field irradiation with concurrent chemotherapy for pelvic lymph node-positive cervical cancer

Purpose

This study aimed to evaluate whether prophylactic extended-field pelvic radiotherapy (EF-PRT) yields better results than standard whole pelvic radiotherapy (WPRT) in patients with pelvic lymph node-positive cervical cancer treated with concurrent chemoradiotherapy (CCRT).

Materials and Methods

A total of 126 cases of stage IB-IVA cervical cancer that had pelvic lymph node involvement in magnetic resonance imaging and were treated with CCRT between 2000 and 2016 were reviewed. None of the patients had paraaortic lymph node (PALN) metastases. The patients were classified to two groups, namely, those treated with EF-PRT, including prophylactic para-aortic radiotherapy, and those treated only with WPRT. The median dose to the PALN area in patients treated with EF-PRT was 45 Gy. All patients received concurrent cisplatin-based chemotherapy.

Results

Overall, 52 and 74 patients underwent EF-PRT and WPRT, respectively. Patient characteristics and irradiated dose were not significantly different, except the dose to the para-aortic area, between the two groups. The median follow-up period was 75.5 months (range, 5 to 195 months). The 10-year cumulative recurrence rate of PALN for EF-PRT vs. WPRT was 6.9% and 10.1% (p = 0.421), respectively. The 10-year disease-free survival and overall survival for EF-PRT vs. WPRT were 69.7% vs. 66.1% (p = 0.748) and 71.7% vs. 72.3% (p = 0.845), respectively. Acute gastrointestinal complications were significantly higher in EF-PRT (n = 21; 40.4%) than WPRT (n = 26; 35.1%) (p = 0.046). Late toxicities were not significantly different in both groups.

Conclusion

In this study, prophylactic radiotherapy for PALN does not have an additional benefit in patients with pelvic lymph node-positive cervical cancer treated with CCRT.

Toxicity and early clinical outcomes in cervical cancer following extended field helical tomotherapy to para-aortic lymph nodes

PURPOSE

To evaluate toxicity and early disease outcome among patients treated for cervical cancer with extended-field helical tomotherapy to the para-aortic nodes.

PATIENTS AND METHODS

Thirty-eight patients (International Federation of Gynecology and Obstetrics [FIGO] stage IB2-IVA) from four institutions received extended-field helical tomotherapy and were retrospectively evaluated. All had nodal disease. Para-aortic lymph nodes were involved in 31 patients. Patients were assessed for toxicity using version 4 of the National Cancer Institute's common terminology criteria for adverse events. Survival curves were plotted using Kaplan-Meier estimates.

RESULTS

All patients underwent radiation to the tumor region (median dose: 45Gy; range: 44-66Gy), pelvic lymph nodes and para-aortic lymph nodes (median dose: 45Gy; range: 44-60Gy). The median dose to positive lymph nodes was 55Gy (range: 45-65Gy). All received platinum-based chemotherapy (31 concurrently). The median follow-up was 15months. Acute toxicity events observed included one patient with grade 5 febrile neutropenia, 11 patients (29%) with grade 3 hematologic complications. Grades 3-4 gastrointestinal and genitourinary toxicities occurred in six (16%) and four (11%) patients, respectively. Three patients had grade 3 pelvic pain (8%). The 6- and 18-month overall survival rates were 94.7 and 63.9%, respectively. The 18-month locoregional control, disease-free survival, and late grade 3 toxicity rates were 60.2, 43.3 and 7.3%, respectively.

CONCLUSION

Extended-field helical tomotherapy was associated with low rates of acute gastrointestinal and genitourinary toxicities with early survival and locoregional control similar to other published series.

Kidney-Sparing Methods for Extended-Field Intensity-Modulated Radiotherapy (EF-IMRT) in Cervical Carcinoma Treatment

Coplanar extended-field intensity-modulated radiation therapy (EF-IMRT) targeting the whole-pelvic and para-aortic lymph nodes in patients with advanced cervical cancer results in impaired creatinine clearance. An improvement in renal function cannot be expected unless low-dose (approximately 10 Gy) kidney exposure is reduced. The dosimetric method should be considered during EF-IMRT planning to further reduce low-dose exposure to the kidneys. To assess the usefulness of non-coplanar EF-IMRT with kidney-avoiding beams to spare the kidneys during cervical carcinoma treatment in dosimetric analysis between non-coplanar and coplanar EF-IMRT, we compared the doses of the target organ and organs at risk, including the kidney, in 10 consecutive patients. To estimate the influence of EFRT on renal dysfunction, creatinine clearance values after treatment were also examined in 18 consecutive patients. Of these 18 patients, 10 patients who were included in the dosimetric analysis underwent extended field radiation therapy (EFRT) with concurrent chemotherapy, and eight patients underwent whole-pelvis radiation therapy with concurrent chemotherapy to treat cervical carcinoma between April 2012 and March 2015 at our institution. In the dosimetric analysis, non-coplanar EF-IMRT was effective at reducing low-dose (approximately 10 Gy) exposure to the kidneys, thus maintaining target coverage and sparing other organs at risk, such as the small bowel, rectum, and bladder, compared with coplanar EF-IMRT. Renal function in all 10 patients who underwent EFRT, including coplanar EF-IMRT (with kidney irradiation), was low after treatment, and differed significantly from that of the eight patients who underwent WPRT (no kidney irradiation) 6 months after the first day of treatment (P = 0.005). In conclusion, non-coplanar EF-IMRT should be considered in patients with advanced cervical cancer, particularly in patients with a long life expectancy or with pre-existing renal dysfunction.

Extended field intensity-modulated radiotherapy plus concurrent nedaplatin treatment in cervical cancer

The present study assessed the efficacy and toxicity of definitive extended-field intensity-modulated radiotherapy (EF-IMRT) plus concurrent chemotherapy in cervical cancer. A total of 48 patients with cervical cancer received the planning target volume between 39.6 and 50.4 Gy in 1.8-2.0 Gy daily fractions, while the enlarged pelvic and/or para-aortic nodes were treated with a total dose of 55-60 Gy in 2.0-2.4 Gy daily fractions using simultaneous integrated boost-IMRT. All patients underwent high dose-rate brachytherapy. Concurrent to EF-IMRT, nedaplatin was administered weekly at a median dose of 30 mg/m² (range, 25-40 mg/m²) for 5 weeks with a total of 150 mg/m². Of the 48 patients, 46 patients exhibited initial complete responses and 2 patients had partial responses, with a response rate of 100%. After 4-24 months of treatment, 12 patients (27.08%) had local and/or distant failure and 39 patients (81.25%) were alive at the last follow-up. The 12-month overall survival (OS) and disease-free survival (DFS) were 87.5 and 75.8%, respectively, while the 24-month OS and DFS were 69.7 and 49.7%, respectively. Grade ≥3 acute neutropenia and thrombcytopenia occurred in 20 (41.7%) and 4 (8.3%) patients, respectively, while 2 patients (4.2%) developed grade ≥3 diarrhea and 2 (4.2%) had grade ≥3 late toxicities. However, no patients exhibited grade ≥3 vomiting. Thus, concurrent nedaplatin chemotherapy with definitive EF-IMRT was effective and relatively safe for treating patients with cervical cancer. Furthermore, EF-IMRT was able to deliver ≤60 Gy to enlarged para-aortic and/or pelvic nodes using simultaneous integrated boost without increased acute and late gastrointestinal toxicity.

Simultaneous modulated accelerated radiotherapy in cervical cancer with retroperitoneal lymph node metastasis after radical hysterectomy and pelvic lymphadenectomy

OBJECTIVE

To compare the dosimetry, toxicity, and efficacy of simultaneous modulated accelerated radiotherapy (SMART) with 3-dimensional conformal radiotherapy (3DCRT) in cervical cancer with retroperitoneal lymph node metastasis after radical hysterectomy and pelvic lymphadenectomy.

METHODS

Total 32 patients who underwent SMART were retrospectively evaluated. Daily fractions of 2.2 to 2.4 Gy and 1.8 to 2 Gy were prescribed and delivered to gross tumor volume and clinical target volume to a total dose of 63.8 and 52.2 Gy, respectively. A 3DCRT plan was designed for the SMART group and planned to deliver the same prescribed dose. The doses of organs at risk (OARs) were compared. Thirty-six patients who received 3DCRT were used to compare the target dose, toxicities, and efficacy with 32 cases who received SMART.

RESULTS

The mean doses delivered to gross tumor volume and clinical target volume were significantly higher in the SMART group than in the 3DCRT group (63.8 vs 55.2 Gy [P < 0.01] and 52.5 vs 48.6 Gy [P < 0.01], respectively). For SMART plan, the doses of OARs were significantly lower than that of 3DCRT plans (small intestine: 25.1 vs 30.9 Gy [P < 0.01], bladder: 35.3 vs 46.3 [P < 0.01], and rectum: 31.7 vs 43.7 [P = 0.002], respectively). The patients experienced less acute and late toxicities in the SMART group (acute toxicities: enteroproctitis, P = 0.019; cystitis, P = 0.013; leukopenia, P = 0.025; late toxicities: enteroproctitis, P = 0.007; and cystitis, P = 0.026, respectively). No significant difference was found for 1-year survival (78.7% vs 67.7%, P = 0.222), but SMART group had a higher 2-year survival rate (2-year: 63.1% vs 39.1%, P = 0.029).

CONCLUSIONS

Simultaneous modulated accelerated radiotherapy plans yielded higher dose to the targets and better sparing of OARs than did 3DCRT in cervical cancer with retroperitoneal lymph node metastasis after radical hysterectomy and pelvic lymphadenectomy. Simultaneous modulated accelerated radiotherapy provided better clinical outcomes than did 3DCRT. Long-term follow-up and studies involving more patients are needed to confirm our results.

Dose escalated intensity modulated radiotherapy in the treatment of cervical cancer

PURPOSE

Standard dose of external beam radiotherapy seems to be insufficient for satisfactory control of loco-regionally advanced cervical cancer. Aim of our study is to evaluate the outcome as well as early and chronic toxicities in patients with loco-regionally advanced cervical cancer, treated with dose escalated intensity modulated radiotherapy (IMRT) combined with cisplatin chemotherapy.

MATERIAL AND METHODS

Thirty-nine patients with cervical carcinoma FIGO stage IB2 - IVA were treated with curative intent between 2006 and 2010. The dose of 50.4 Gy was prescribed to the elective pelvic nodal volume. Primary tumors < 4 cm in diameter (n = 6; 15.4 %) received an external beam radiotherapy (EBRT) boost of 5.4 Gy, primary tumors > 4 cm in diameter (n = 33; 84.6 %) received an EBRT boost of 9 Gy. Patients with positive lymph nodes detected with (18)FDG-PET/CT (n = 22; 56.4 %) received a boost to a total dose of 59.4 - 64.8 Gy. The para-aortic region was included in the radiation volume in 8 (20.5 %) patients and in 5 (12.8 %) patients the para-aortic macroscopic lymph nodes received an EBRT boost. IMRT was followed with a 3D planned high dose rate intrauterine brachytherapy given to 36 (92.3 %) patients with a total dose ranging between 15-18 Gy in three fractions (single fraction: 4-6.5 Gy). Patients without contraindications (n = 31/79.5 %) received concomitantly a cisplatin-based chemotherapy (40 mg/kg) weekly. Toxicities were graded according to the common terminology criteria for adverse events (CTCAE v 4.0).

RESULTS

Mean overall survival for the entire cohort was 61.1 months (±3.5 months). Mean disease free survival was 47.2 months (±4.9 months) and loco-regional disease free survival was 55.2 months (±4.4 months). 65 % of patients developed radiotherapy associated acute toxicities grade 1, ca. 30 % developed toxicities grade 2 and just two (5.2 %) patients developed grade 3 toxicities, one acute diarrhea and one acute cystitis. 16 % of patients had chronic toxicities grade 1, 9 % grade 2 and one patient (2.6 %) toxicities grade 3 in the form of vaginal dryness.

CONCLUSION

Dose escalated IMRT appears to have a satisfactory outcome with regards to mean overall survival, disease free and loco-regional disease free survival, whereas the treatment-related toxicities remain reasonably low.

A novel dynamic field-matching technique for treatment of patients with para-aortic node-positive cervical cancer: Clinical experience

AIM

To report outcomes for patients with para-aortic lymph node positive cervical cancer treated with a dynamic field-matching technique.

BACKGROUND

PET staging of cervical cancer has increased identification of patients with para-aortic lymph node metastasis. IMRT enables dose escalation in this area, but matching IMRT fields with traditional whole pelvis fields presents a challenge.

MATERIALS AND METHODS

From 2003 to 2012, 20 patients with cervical cancer and para-aortic lymph node metastasis were treated utilizing the dynamic field-matching technique. As opposed to single-isocenter half-beam junction techniques, this technique employs wedge-shaped dose junctions for the abutment of fields. We reviewed the records of all patients who completed treatment with the technique and abstracted treatment, toxicity, and disease-related outcome data for analysis.

RESULTS

Median prescribed dose to the whole pelvis field was 45 Gy and para-aortic IMRT field 50.4 Gy. All but 3 patients underwent HDR (13 pts) or LDR (4 pts) brachytherapy. All patients developed lower GI toxicity; 10 grade 1, 9 grade 2, and 1 grade 4 (enterovaginal fistula). Median DFS was 12.4 months with 1 and 2-year DFS 60.0% and 38.1%. One-year OS was 83.7% and 2-year OS, 64.4%. A total of 10 patients developed recurrence; none occurred at the matched junction.

CONCLUSIONS

The dynamic field-matching technique provides a means for joining conventional whole pelvis fields and para-aortic IMRT fields that substantially reduces dose deviations at the junction due to field mismatch. Treatment with the dynamic matching technique is simple, effective, and tolerated with no apparent increase in toxicity.

Long-term follow-up results of simultaneous integrated or late course accelerated boost with external beam radiotherapy to vaginal cuff for high risk cervical cancer patients after radical hysterectomy

BACKGROUND

To assess the safety and efficacy of simultaneous integrated boost (SIB) or late course accelerated boost (LCAB) with external beam radiotherapy (EBRT) to the vaginal cuff for high risk cervical cancer patients after radical hysterectomy.

METHODS

Between October 2009 and January 2012, patients with high risk cervical cancer who had undergone radical surgery followed by EBRT to the vaginal cuff were enrolled. Patients were treated with either intensity modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) with SIB (arm A) or IMRT/VMAT to the pelvis followed by LCAB (arm B) to vaginal cuff. In arm A, the pelvic and boost doses were 50.4 Gy and 60.2 Gy in 28 fractions, respectively. In arm B, pelvic irradiation to 50 Gy in 25 fractions followed by a boost of 9 Gy in 3 fractions were delivered. Chemotherapy was given concurrently.

RESULTS

Overall, 80 patients were analyzed in this study (42 in arm A, 38 in arm B). In arm A and B, median follow-up was 37 and 32 months, respectively. The 3-year disease-free survival and overall survival in arms A vs B were 88.7% vs. 93.4% (p = 0.89), and 91.8% vs.100% (p = 0.21), respectively. The 3-year local-regional control and distant failure were 97.6% vs. 100% (p = 0.34), and 4.8% vs. 5.3% (p = 0.92), respectively. Grade 3-4 acute leukopenia and dermatitis were seen in 11 (26.2%) and 8 (19.0%) patients in Arm A, vs. 7 (17.8%) and 6 (15.8%) patients in Arm B, respectively (p > 0.05). Only Grade 1-2 chronic gastrointestinal (GI) and genitourinary (GU) toxicities were observed.

CONCLUSIONS

Our results indicate that both SIB and LCAB to vaginal cuff for high risk cervical cancer patients after radical hysterectomy are associated with excellent survival, local control and low toxicity.

Distribution pattern of lymph node metastases and its implication in individualized radiotherapeutic clinical target volume delineation of regional lymph nodes in patients with stage IA to IIA cervical cancer

BACKGROUND

To study the distribution pattern of lymph node metastases of stage IA to IIA cervical cancer and to clarify the individualized clinical target volume delineation of regional lymph nodes (CTVn).

METHODS

A total of 665 cases with International Federation Gynecology and Obstetrics stage IA to IIA cervical cancer who underwent radical hysterectomy and pelvic lymphadenectomy were retrospectively reviewed. The clinicopathological factors related to lymph node metastases were analyzed using logistic regression analysis.

RESULTS

Pelvic lymph node metastases were found in 168 of 665 patients resulting in a metastasis rate of 25.3%. Binary logistic regression analysis showed that age, lymph vascular space involvement, and deep stromal invasion statistically influenced pelvic lymph node metastases (p = 0.017, < 0.001, < 0.001, respectively). Pathological morphology type, lymph node metastases of the obturator, the external iliac and internal iliac, and the para-aortic had a strong influence on lymph node metastases of the common iliac (p = 0.022, 0.003, < 0.001, 0.009, respectively). Tumor size and lymph node metastases of the common iliac were significantly related to lymph node metastases of the para-aortic (p = 0.045, < 0.001, respectively). Lymph node metastases of the obturator, the external iliac and internal iliac were strongly correlated to lymph node metastases of the circumflex iliac node distal to the external iliac node (CINDEIN; p = 0.027, 0.024, respectively).

CONCLUSIONS

Factors related to lymph node metastases should be comprehensively considered to design and tailor CTVn for radiotherapy of cervical cancer. Selective regional irradiation including the correlated lymphatic drainage regions should be performed.

Methods, safety, and early clinical outcomes of dose escalation using simultaneous integrated and sequential boosts in patients with locally advanced gynecologic malignancies

OBJECTIVE

To evaluate the safety of dose escalated radiotherapy using a simultaneous integrated boost technique in patients with locally advanced gynecological malignancies.

METHODS

Thirty-nine women with locally advanced gynecological malignancies were treated with intensity modulated radiation therapy utilizing a simultaneous integrated boost (SIB) technique for gross disease in the para-aortic and/or pelvic nodal basins, sidewall extension, or residual primary disease. Women were treated to 45Gy in 1.8Gy fractions to elective nodal regions. Gross disease was simultaneously treated to 55Gy in 2.2Gy fractions (n=44 sites). An additional sequential boost of 10Gy in 2Gy fractions was delivered if deemed appropriate (n=29 sites). Acute and late toxicity, local control in the treated volumes (LC), overall survival (OS), and distant metastases (DM) were assessed.

RESULTS

All were treated with a SIB to a dose of 55Gy. Twenty-four patients were subsequently treated with a sequential boost to a median dose of 65Gy. Median follow-up was 18months. Rates of acute>grade 2 gastrointestinal (GI), genitourinary (GU), and hematologic (heme) toxicities were 2.5%, 0%, and 30%, respectively. There were no grade 4 acute toxicities. At one year, grade 1-2 late GI toxicities were 24.5%. There were no grade 3 or 4 late GI toxicities. Rates of grade 1-2 late GU toxicities were 12.7%. There were no grade 3 or 4 late GU toxicities.

CONCLUSION

Dose escalated radiotherapy using a SIB results in acceptable rates of acute toxicity.

Low-Dose, Prophylactic, Extended-Field, Intensity-Modulated Radiotherapy Plus Concurrent Weekly Cisplatin for Patients With Stage IB2-IIIB Cervical Cancer, Positive Pelvic Lymph Nodes, and Negative Para-aortic Lymph Nodes

Objective

The objective of this study was to assess prospectively the clinical outcomes of low-dose prophylactic extended-field, intensity-modulated radiotherapy (IMRT) plus concurrent weekly cisplatin for patients with stage IB2-IIIB cervical cancer, positive pelvic lymph nodes (PLNs), and negative para-aortic lymph nodes (PALNs).

Methods

Thirty-two patients with stage IB2-IIIB cervical cancer with positive PLN and negative PALN were included prospectively. All lymph nodes were assessed with positron emission tomography. The PALN field, including lymphatics from the superior border of L1 to the L4-L5 interphase, was irradiated concurrently with pelvic IMRT with a prescribed dose of 40 Gy in 25 fractions. Chemotherapy consisted of cisplatin delivered weekly at a dose of 40 mg/m2. Using historical controls treated with pelvic radiotherapy, the survival curves were compared to assess the difference between the 2 treatment periods.

Results

Thirty-one patients completed the allocated extended-field IMRT, and all finished the planned pelvic IMRT and brachytherapy. Acute ≥ grade 3 gastrointestinal, genitourinary, and hematologic toxicities were seen in 2, 1, and 18 patients, respectively. During a median follow-up of 33 months, 5 patients developed out-field distant recurrences. One patient had a late grade 3 gastrointestinal complication, and 1 patient had genitourinary toxicity. The 3-year actuarial overall survival, disease-free survival, and distant metastasis–free survival for the study cohort and historic controls were 87% versus 62% (P = 0.02), 82% versus 54% (P = 0.02), and 79% versus 57% (P = 0.01), respectively.

Conclusions

Extended-field IMRT of 40 Gy to the PALN plus concurrent cisplatin can effectively eradicate subclinical disease at the PALN and improve the outcome for patients with PLN-positive stage IB2-IIIB cervical cancer.

IMRT with ¹⁸FDG-PET\CT based simultaneous integrated boost for treatment of nodal positive cervical cancer

Background

To evaluate toxicity and outcome of intensity modulated radiotherapy (IMRT) with simultaneous integrated boost (SIB) to the positive lymph nodes in patients with loco-regional advanced cervical cancer (LRACC).

Methods

The study population comprised ten patients with ¹⁸FDG-PET\CT positive lymph nodes (LNs), who underwent chemoradiation with IMRT and SIB. A dose of 50.4 Gy, in daily fractions of 1.8 Gy, was delivered to primary tumor and draining LNs. Primary tumor received an additional external beam boost to a total dose of 55.8 Gy. A SIB of 62 Gy, in daily fractions of 2 Gy, was delivered to the ¹⁸FDG-PET\CT positive LNs. Finally, a high dose rate brachytherapy (HDRB) boost (15 – 18 Gy) was administered to the primary tumor. The primary goal of this study was to evaluate acute and early late toxicity and loco-regional control.

Results

The median number of irradiated LNs per patient was 3 (range: 1–6) with a median middle nodal SIB-volume of 26.10 cm³ (range, 11.9-82.50 cm³). Median follow-up was 20 months (range, 12 to 30 months). Acute and late grade 3 toxicity was observed in 1 patient. Three of the patients developed a recurrence, one in the form of a local tumor relapse, one had a paraaortic LN metastasis outside the treated volume and the last one developed a distant metastasis.

Conclusion

IMRT with SIB in the region of 18FDG-PET positive lymph nodes appears to be an effective therapy with acceptable toxicity and might be useful in the treatment of patients with locally advanced cervical cancer.

Definitive extended field intensity-modulated radiotherapy and concurrent cisplatin chemosensitization in the treatment of IB2-IIIB cervical cancer

OBJECTIVE

To assess the toxicity of delivering extended field intensity-modulated radiotherapy (EF-IMRT) and concurrent cisplatin chemotherapy for locally advanced cervical carcinoma.

METHODS

Forty-five patients who underwent EF-IMRT and concurrent cisplatin chemotherapy for the treatment of stage IB2 to IIIB cervical cancer were retrospectively reviewed. The clinical target volume included all areas of gross and potentially microscopic disease and regional lymph node regions. All patients underwent high-dose-rate brachytherapy. The acute and late toxicity were scored using the Common Terminology Criteria for Adverse Events and the Radiation Therapy Oncology Group late radiation morbidity scoring criteria, respectively.

RESULTS

The median follow-up was 28 months (range, 5 to 62 months). Forty-two patients had a complete response, and three had a persistent disease. Of those 42 patients, 15 patients (35.7%) had recurrence. The regions of recurrence were in-field in 2 patients and out-field in 13 patients. Acute grade ≥3 gastrointestinal, genitourinary and hematologic toxicity occurred in 3, 1, and 9 patients, respectively. Three patients (6.7%) suffered from late grade 3 toxicities. Seven patients experienced ovarian transposition, 5 of those patients (71%) maintained ovarian function. Thirty-eight patients (84.4%) were alive at the last follow-up.

CONCLUSION

Concurrent cisplatin chemotherapy with EF-IMRT was safe. The acute and late toxicities are acceptable. EF-IMRT provides an opportunity to preserve endocrine function for patients with ovarian transposition.

Intensity modulated radiotherapy in gynecologic cancers: hope, hype or hyperbole?

Significant advances have occurred within the field of radiation oncology within the past few decades. Treatment with external beam radiotherapy has progressed from treatment fields planned from bony anatomy seen on planar X-rays, to 3-dimensional planning utilizing fused MRI's and PET images. Recently, intensity modulated radiotherapy (IMRT) has been integrated into many areas within radiation oncology, and its role in the treatment of gynecologic cancers is evolving. Potentials exist for improvements in both treatment toxicity, as well as improved efficacy through advances in treatment delivery. Unique challenges are also raised, however. With increased accuracy of treatment delivery comes the need for greater accuracy in target delineation and incorporation of motion to prevent marginal misses. The goal of this review is to evaluate the use of IMRT in cervical and endometrial cancers, including the results of dosimetric and clinical studies to date. In addition, potential disadvantages and challenges of IMRT integration are discussed.

Extended-Field Intensity-Modulated Radiotherapy and Concurrent Cisplatin-Based Chemotherapy for Postoperative Cervical Cancer With Common Iliac or Para-Aortic Lymph Node Metastases: A Retrospective Review in a Single Institution

Objective

Retrospectively, to assess the toxicity of delivering postoperative extended-field intensity-modulated radiotherapy (EF-IMRT) and concurrent cisplatin chemotherapy for patients with cervical cancer with a pathologically confirmed positive common iliac node and/or a para-aortic node.

Methods

Each patient received postoperative EF-IMRT and concurrent cisplatin chemotherapy. The clinical target volume included regional lymph node regions (obturator; common, internal, and external iliac nodal regions; presacral region; and para-aortic regions) and the upper 2.0 cm of the vagina and paravaginal soft tissue lateral to the vagina. The acute and late toxicity were scored using the Common Terminology Criteria for Adverse Events (CTCAE) and the Radiation Therapy Oncology Group late radiation morbidity scoring criteria, respectively.

Results

Fifty-eight patients were treated with postoperative EF-IMRT and concurrent cisplatin chemotherapy. The median follow-up was 34 months. Eighteen patients (31%) had recurrence. The region of recurrence was in-field in 2 patients (3.4%) and out-field in 16 patients (27.6%). Acute grade 3 or higher gastrointestinal, genitourinary, and hematologic toxicity occurred in 2, 1, and 11patients, respectively. Three patients (5.1%) had late grade 3 toxicities. Thirteen patients experienced ovarian transposition; of these, 10 patients (77%) maintained ovarian function. Forty-one patients (71%) were alive at the last follow-up.

Conclusions

Concurrent cisplatin chemotherapy with postoperative EF-IMRT was safe and well tolerated. The acute and late toxicities are acceptable. The locoregional control rates are hopeful, although distant metastases continue to be the primary mode of failure. Postoperative EF-IMRT provides an opportunity to preserve endocrine function for patients with ovarian transposition.

Rectum separation in patients with cervical cancer for treatment planning in primary chemo-radiation

PURPOSE

To proof feasibility of hydrogel application in patients with advanced cervical cancer undergoing chemo-radiation in order to reduce rectal toxicity from external beam radiation as well as brachytherapy.

MATERIAL AND METHODS

Under transrectal sonographic guidance five patients with proven cervical cancer underwent hydro gel (20 cc) instillation into the tip of rectovaginal septum adherent to posterior part of the visible cervical tumor. Five days after this procedure all patients underwent T2 weighted transversal and sagittal MRI for brachytherapy planning. MRI protocol included T2 weighted fast spin echo (FSE) imaging in sagittal, coronal and para-axial orientation using an 1.5 Tesla MRI. Separation of anterior rectal wall and cervix was documented.

RESULTS

Hydrogel application was uneventful in all patients and no toxicity was reported. Separation ranged from 7 to 26 mm in width (median 10 mm). The length of the separation varied between 18 and 38 mm (median 32 mm). In all patients displacement was seen in the posterior vaginal fornix, and/or at the deepest part of uterine cervix depending on the extension of the cul-de-sac in correlation to the posterior wall of the uterus. In patients with bulky tumor and/or deep (vaginal) extend of peritoneal cavity tumour was seen mainly cranial from the rectovaginal space and therefore above the hydrogeI application. Only in the extra-peritoneal (lower) part of the cervix a good separation could be achieved between the rectum and cervix.

CONCLUSION

Hydrgel instillation in patients with cervial cancer undergoing chemoradiation is safe and feasible. Because of the loose tissue of the cul-de-sac and its intra- and extraperitoneal part, hydrogel instillation of 20 cc did not result in a sufficient separation of the cervix from anterior wall.

Nodal-staging surgery for locally advanced cervical cancer in the era of PET

Chemoradiation therapy is deemed the standard treatment by many North American and European teams for treatment of locally advanced cervical cancer. The prevalence of para-aortic nodal metastasis in these tumours is 10-25%. PET (with or without CT) is the most accurate imaging modality to assess extrapelvic disease in such tumours. The true-positive rate of PET is high, suggesting that surgical staging is not necessary if uptake takes place in the para-aortic region. Nevertheless, false-negative results (in the para-aortic region) have been recorded in 12% of patients, rising to 22% in those with uptake during PET of the pelvic nodes. In such situations, laparoscopic surgical para-aortic staging still has an important role for detection of patients with occult para-aortic spread misdiagnosed on PET or PET-CT, allowing optimisation of treatment (extension of radiation therapy fields to include the para-aortic area). Complications of the laparoscopic procedure were noted in 0-7% of patients. Survival of individuals (missed by PET) with para-aortic nodal metastasis of 5 mm or less (and managed by extended field chemoradiation therapy) seems to be similar to survival of those without para-aortic spread, suggesting a positive therapeutic effect of the addition of staging surgery. Nevertheless, the effect on survival of potential delay of chemoradiation owing to use of PET and staging surgery, and acute and late complications of surgery followed by chemoradiation therapy (particularly in case of extended field chemoradiation to para-aortic area), need to be studied.

American Brachytherapy Society consensus guidelines for locally advanced carcinoma of the cervix. Part I: general principles

PURPOSE

To develop brachytherapy recommendations covering aspects of pretreatment evaluation, treatment, and dosimetric issues for locally advanced cervical cancer.

METHODS

Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated recommendations for locally advanced (Federation of Gynecology and Obstetrics Stages IB2-IVA) cervical cancer based on literature review and clinical experience.

RESULTS

The ABS recommends the use of brachytherapy as a component of the definitive treatment of locally advanced cervical carcinoma. Precise applicator placement is necessary to maximize the probability of achieving local control without major side effects. The ABS recommends a cumulative delivered dose of approximately 80-90Gy for definitive treatment. The dose delivered to point A should be reported for all brachytherapy applications regardless of treatment-planning technique. The ABS also recommends adoption of the Groupe Européen Curiethérapie-European Society of Therapeutic Radiation Oncology (GEC-ESTRO) guidelines for contouring, image-based treatment planning, and dose reporting. Interstitial brachytherapy may be considered for a small proportion of patients whose disease cannot be adequately encompassed by intracavitary application. It should be performed by practitioners with special expertise in these procedures.

CONCLUSIONS

Updated ABS recommendations are provided for brachytherapy for locally advanced cervical cancer. Practitioners and cooperative groups are encouraged to use these recommendations to formulate their clinical practices and to adopt dose-reporting policies that are critical for outcome analysis.

[Dosimetric comparison between the intensity modulated radiotherapy with fixed field and Rapid Arc of cervix cancer]

PURPOSE

Concurrent radiochemotherapy is the standard treatment for locally advanced cervical cancer. This treatment is responsible for bowel and hematologic toxicities. The use of intensity-modulated radiotherapy (IMRT), in static beams, allows a decrease of this toxicity. The technique of RapidArc(®) IMRT could lower the dose delivered to the organs at risk and improve the homogeneity of the planning target volume coverage, while decreasing the processing time.

PATIENTS AND MATERIALS

For 20 patients, treatment plans performed with IMRT and RapidArc(®) were compared. The target volumes were: the clinical target volume (gross tumour volume, uterus, upper third of the vagina, the hypogastric, iliac and presacral nodal regions), and the planning target volume (clinical target volume+1cm). The delineated organs at risk were: rectum, bladder, bowel and bone marrow. The dose was 45 Gy in 25 fractions. IMRT were delivered with five beams and RapidArc(®) with two arcs. The comparisons were made by the non-parametric test of Wilcoxon.

RESULTS

Medium coverage of the planning target volume was better with RapidArc(®) (P=0.01). It was also better regarding the sparing of bowel (P=0.01) and IMRT was better regarding the sparing of bladder (P=0.01) and rectum (P=0.05). The total volume receiving 20 Gy was less important with RapidArc(®) (P<0.001). RapidArc(®) allowed to decrease the treatment time (3 versus 12 minutes with IMRT) and the number of monitor units (MU) (376.5 versus 962.2, on average, P=0.0001).

CONCLUSION

The technique of RapidArc(®) seems to obtain better dosimetric results compared to RCMI, with fewer MU, and a significant decrease in treatment time.

Dosimetric comparison of combined intensity-modulated radiotherapy (IMRT) and proton therapy versus IMRT alone for pelvic and para-aortic radiotherapy in gynecologic malignancies

PURPOSE

To perform a dosimetric comparison of intensity-modulated radiotherapy (IMRT), passive scattering proton therapy (PSPT), and intensity-modulated proton therapy (IMPT) to the para-aortic (PA) nodal region in women with locally advanced gynecologic malignancies.

METHODS AND MATERIALS

The CT treatment planning scans of 10 consecutive patients treated with IMRT to the pelvis and PA nodes were identified. The clinical target volume was defined by the primary tumor for patients with cervical cancer and by the vagina and paravaginal tissues for patients with endometrial cancer, in addition to the regional lymph nodes. The IMRT, PSPT, and IMPT plans were generated using the Eclipse Treatment Planning System and were analyzed for various dosimetric endpoints. Two groups of treatment plans including proton radiotherapy were created: IMRT to pelvic nodes with PSPT to PA nodes (PSPT/IMRT), and IMRT to pelvic nodes with IMPT to PA nodes (IMPT/IMRT). The IMRT and proton RT plans were optimized to deliver 50.4 Gy or Gy (relative biologic effectiveness [RBE)), respectively. Dose-volume histograms were analyzed for all of the organs at risk. The paired t test was used for all statistical comparison.

RESULTS

The small-bowel V(20), V(30), V(35), andV(40) were reduced in PSPT/IMRT by 11%, 18%, 27%, and 43%, respectively (p < 0.01). Treatment with IMPT/IMRT demonstrated a 32% decrease in the small-bowel V(20). Treatment with PSPT/IMRT showed statistically significant reductions in the body V(5-20); IMPT/IMRT showed reductions in the body V(5-15). The dose received by half of both kidneys was reduced by PSPT/IMRT and by IMPT/IMRT. All plans maintained excellent coverage of the planning target volume.

CONCLUSIONS

Compared with IMRT alone, PSPT/IMRT and IMPT/IMRT had a statistically significant decrease in dose to the small and large bowel and kidneys, while maintaining excellent planning target volume coverage. Further studies should be done to correlate the clinical significance of these findings.

Intensity-modulated radiation therapy versus para-aortic field radiotherapy to treat para-aortic lymph node metastasis in cervical cancer: prospective study

AIM

To compare dosimetry, efficacy, and toxicity of intensity-modulated radiation therapy (IMRT) with para-aortic field radiotherapy in patients with para-aortic lymph node (PALN) metastasis of cervical cancer.

METHODS

This prospective study examined 60 patients with cervical cancer with PALN metastasis who underwent whole-pelvis radiotherapy followed by brachytherapy between November 1, 2004 and May 31, 2008. After 3 cycles of chemotherapy, patients were serially allocated into two groups and treated with IMRT or para-aortic field RT at doses of 58-68 Gy and 45-50 Gy, respectively. Treatment response was evaluated and toxicities were assessed. Patients in the IMRT group were treated with both para-aortic field RT and IMRT in order to compare the exposure dose of organs at risk.

RESULTS

In the IMRT group, the mean dose delivered to the planning target volume was 67.5 Gy. At least 99% of the gross tumor volume received effective coverage and radical dose (median, 63.5 Gy; range, 54.5-66) during treatment. IMRT plans yielded better dose conformity to the target and better sparing of the spinal cord and small intestine than para-aortic field RT. The IMRT patients experienced less acute and chronic toxicities. The IMRT group also had higher 2- and 3-year survival rates than the para-aortic RT group (2-year, 58.8% vs 25.0%, P = 0.019; 3-year, 36.4% vs 15.6%, P = 0.016). However, no significant difference was found in 1-year survival (67.7% vs 51.3%, P =0.201). The median survival in the IMRT group was 25 months (range, 3 to 37 months). The actuarial overall survival, disease-free survival, and locoregional control rates at 2 years were 67%, 77%, and 88%, respectively, in the IMRT group.

CONCLUSIONS

IMRT provides better clinical outcomes than para-aortic field radiotherapy in patients with PALN metastasis. However, cervical local and distal recurrence remain a problem. Long-term follow-up and studies involving more patients are needed to confirm our results.

Intensity-modulated radiotherapy in patients with cervical cancer. An intra-individual comparison of prone and supine positioning

Background

Chemoradiation for cervical cancer patients is associated with considerable gastrointestinal toxicity. Intensity-modulated radiotherapy (IMRT) has demonstrated superiority in terms of target coverage and normal tissue sparing in comparison to conventional 3D planning in gynaecological malignancies. Whether IMRT in prone (PP) or supine position (SP) might be beneficial for cervical cancer patients remains partially unanswered.

Methods

10 patients on FIGO stage IB-III cervical cancer, 6 patients for definitive and 4 patients for adjuvant external beam pelvic RT, were planned in PP and SP using a 7-field IMRT technique. IMRT plans for PP and SP (mean dose, D_mean 50.4 Gy) were optimized in terms of PTV coverage (1^st priority) and small bowel sparing (2^nd priority). A comparison of DVH parameters for PTV, small bowel, bladder, and rectum was performed.

Results

The comparison showed a similar PTV coverage of 95% of the prescribed dose and for target conformity in IMRT plans (PP, SP). PTV, rectum and bladder volumes were comparable for PP and SP. Significantly larger volumes of small bowel were found in PP (436 cc, + 35%, p = 0.01). PP decreased the volume of small bowel at 20-50.4 Gy (p < 0.05) and increased the rectum volumes covered by doses from 10-40 Gy (p < 0.01), the V50.4 was < 5% in both treatment positions. Bladder sparing was significant better at 50.4 Gy (p = 0.03) for PP.

Conclusion

In this dosimetric study, we demonstrated that pelvic IMRT in prone position for patients with cervical cancer seems to be beneficial in reducing small bowel volume at doses ≥20 Gy while providing similar target coverage and target conformity. The use of frequent image guidance with KV (kilovolt) or MV (megavolt) computertomography can reduce set-up deviations, and treatment in prone position can be done with a higher set-up accuracy. Clinical outcome studies are needed to affirm lower toxicity.

Consensus guidelines for delineation of clinical target volume for intensity-modulated pelvic radiotherapy for the definitive treatment of cervix cancer

PURPOSE

Accurate target definition is vitally important for definitive treatment of cervix cancer with intensity-modulated radiotherapy (IMRT), yet a definition of clinical target volume (CTV) remains variable within the literature. The aim of this study was to develop a consensus CTV definition in preparation for a Phase 2 clinical trial being planned by the Radiation Therapy Oncology Group.

METHODS AND MATERIALS

A guidelines consensus working group meeting was convened in June 2008 for the purposes of developing target definition guidelines for IMRT for the intact cervix. A draft document of recommendations for CTV definition was created and used to aid in contouring a clinical case. The clinical case was then analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with kappa statistics as a measure of agreement between participants.

RESULTS

Nineteen experts in gynecological radiation oncology generated contours on axial magnetic resonance images of the pelvis. Substantial STAPLE agreement sensitivity and specificity values were seen for gross tumor volume (GTV) delineation (0.84 and 0.96, respectively) with a kappa statistic of 0.68 (p < 0.0001). Agreement for delineation of cervix, uterus, vagina, and parametria was moderate.

CONCLUSIONS

This report provides guidelines for CTV definition in the definitive cervix cancer setting for the purposes of IMRT, building on previously published guidelines for IMRT in the postoperative setting.

Intensity-modulated arc therapy with simultaneous integrated boost in the treatment of primary irresectable cervical cancer. Treatment planning, quality control, and clinical implementation

PURPOSE

To report on the planning procedure, quality control, and clinical implementation of intensity-modulated arc therapy (IMAT) delivering a simultaneous integrated boost (SIB) in patients with primary irresectable cervix carcinoma.

PATIENTS AND METHODS

Six patients underwent PET-CT (positron emission tomography-computed tomography) and MRI (magnetic resonance imaging) before treatment planning. Prescription (25 fractions) was (1) a median dose (D(50)) of 62, 58 and 56 Gy to the primary tumor (GTV_cervix), primary clinical target volume (CTV_cervix) and its planning target volume (PTV_cervix), respectively; (2) a D(50) of 60 Gy to the PET-positive lymph nodes (GTV_nodes); (3) a minimal dose (D(98)) of 45 Gy to the planning target volume of the elective lymph nodes (PTV_nodes). IMAT plans were generated using an anatomy-based exclusion tool with the aid of weight and leaf position optimization. The dosimetric delivery of IMAT was validated preclinically using radiochromic film dosimetry.

RESULTS

Five to nine arcs were needed to create valid IMAT plans. Dose constraints on D(50) were not met in two patients (both GTV_cervix: 1 Gy and 3 Gy less). D(98) for PTV_nodes was not met in three patients (1 Gy each). Film dosimetry showed excellent gamma evaluation. There were no treatment interruptions.

CONCLUSION

IMAT allows delivering an SIB to the macroscopic tumor without compromising the dose to the elective lymph nodes or the organs at risk. The clinical implementation is feasible.

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.

Extended-field radiation therapy with whole pelvis radiotherapy and cisplatin chemosensitization in the treatment of IB2-IIIB cervical carcinoma: a retrospective review

OBJECTIVE

This retrospective study evaluated the toxicity of extended-field radiation therapy (EFRT), whole pelvis radiotherapy, and concurrent chemotherapy in patients treated with IB2-IIIB cervical carcinoma.

STUDY DESIGN

Patients treated with EFRT, whole pelvis radiotherapy, and concurrent chemotherapy were analyzed for toxicity. Median prescribed dose to the whole pelvis was 45 Gy (45-50 Gy). Median prescribed dose to the paraaortic lymph nodes was 45 Gy (36-50). Thirty-five patients received cisplatin chemosensitization at a median dose of 40 mg/m(2) (40-51), with a median of 5 cycles (2-6).

RESULTS

Thirty-six patients were treated, 3 with positive paraaortic lymph nodes. The median follow-up interval was 32 months. Twenty-four patients (66.7%) had no evidence of disease at last follow-up. Thirteen patients (36.1%) had recurrence. Fifteen patients (41.7%) experienced acute grade 3 toxicity.

CONCLUSION

Increased toxicity in patients warrants careful patient selection.

Management of early and locally advanced cervical cancer

Cervical cancer is the second most common malignancy in women and the third most common cause of cancer mortality worldwide. While primary and secondary preventions exist, the lack of widespread adoption leaves the treatment of cervical cancer an important oncologic problem. In this article, the management of early and locally advanced cervical carcinoma is reviewed, including staging, imaging, prognostic factors, and primary and adjuvant therapy and their outcomes.

PET-CT in radiation oncology: the impact on diagnosis, treatment planning, and assessment of treatment response

OBJECTIVE

To review the role of hybrid positron emission tomography (PET)-computed tomography (CT) systems in the design and management of cancer patients in the modern radiation oncology practice. PET is co-registered with CT and incorporated into a systematic approach to the staging, management, and assessment of response and surveillance of a variety of oncologic diagnoses.

METHODS

A review of the literature of functional imaging such as PET-CT in staging, treatment plan design, assessment of response and detection of recurrence for tumors involving the head and neck, lung, esophagus, rectum amongst others.

RESULTS

PET and PET-CT offer significant advantages which include more accurate staging which often results in management changes in roughly one-third of patients across a number of disease site. More accurate target definition may augment highly conformal radiation treatment plans using intensity-modulated radiation therapy and stereotactic radiosurgery and radiotherapy.

CONCLUSION

The emerging data appears to suggest the functional imaging may be a more useful tool to evaluate the therapeutic effect of treatment, detect early failures and prognosticate long-term outcome.

Conformal and intensity-modulated radiotherapy for cervical cancer

Three-dimensional radiotherapy planning techniques, including conformal radiotherapy and intensity-modulated radiotherapy, have potential for improving outcomes in cervical cancer. Accurate target volume definition is essential in order to maximise normal tissue sparing while minimising the risk of a geographical miss. This reduction in toxicity provides the option of dose escalation, particularly with simultaneous integrated boost intensity-modulated radiotherapy. The evidence for the current use and potential applications of these techniques in the treatment of cervical cancer are discussed.

Concurrent daily cisplatin and extended-field radiation therapy for carcinoma of the cervix

The aim of this study was to assess acute toxicities of concurrent low-dose daily cisplatin and extended-field radiation therapy (EFRT) for carcinoma of the uterine cervix. Fifteen women with cervical cancer who were treated with concurrent daily low-dose cisplatin and EFRT were analyzed. Daily cisplatin dose was fixed to 8 mg/m(2), which was determined in the preceding phase I study using pelvic radiotherapy. Twelve patients underwent either combined external beam radiation therapy and intracavitary brachytherapy or external beam radiation therapy alone. Three other patients were treated with adjuvant chemoradiotherapy after surgery. A total dose of EFRT ranged from 40 to 45 Gy, with an additional boost to the gross tumor volume up to 50.4-55 Gy. A median total dose of cisplatin during entire radiation therapy course was 224 mg/m(2) (range, 200-240 mg/m(2)). In 14 of 15 patients (93%), daily cisplatin could be delivered continuously as planned without any modification. Administration of cisplatin had to be interrupted in only one patient for only 3 days. Fourteen patients developed grade 2 or worse leukopenia including five after treatment, grade 2 in four, grade 3 in eight, and grade 4 in two. Grade 3 thrombocytopenia was observed in three patients. Grade 2 or worse anemia was observed in 12. Three patients had grade 3 nonhematologic toxicities, diarrhea in two, and nausea/vomiting in one. Although moderate to severe hematologic toxicities are common, this study suggests that concurrent low-dose daily cisplatin and EFRT are feasible. A cumulative cisplatin dose of greater than 200 mg/m(2) during radiation therapy could be achieved by using daily cisplatin dose of 8 mg/m(2).

Clinical outcome in posthysterectomy cervical cancer patients treated with concurrent Cisplatin and intensity-modulated pelvic radiotherapy: comparison with conventional radiotherapy

PURPOSE

To assess local control and acute and chronic toxicity with intensity-modulated radiation therapy (IMRT) as adjuvant treatment of cervical cancer.

METHODS AND MATERIALS

Between April 2002 and February 2006, 68 patients at high risk of cervical cancer after hysterectomy were treated with adjuvant pelvic radiotherapy and concurrent chemotherapy. Adjuvant chemotherapy consisted of cisplatin (50 mg/m(2)) for six cycles every week. Thirty-three patients received adjuvant radiotherapy by IMRT. Before the IMRT series was initiated, 35 other patients underwent conventional four-field radiotherapy (Box-RT). The two groups did not differ significantly in respect of clinicopathologic and treatment factors.

RESULTS

IMRT provided compatible local tumor control compared with Box-RT. The actuarial 1-year locoregional control for patients in the IMRT and Box-RT groups was 93% and 94%, respectively. IMRT was well tolerated, with significant reduction in acute gastrointestinal (GI) and genitourinary (GU) toxicities compared with the Box-RT group (GI 36 vs. 80%, p = 0.00012; GU 30 vs. 60%, p = 0.022). Furthermore, the IMRT group had lower rates of chronic GI and GU toxicities than the Box-RT patients (GI 6 vs. 34%, p = 0.002; GU 9 vs. 23%, p = 0.231).

CONCLUSION

Our results suggest that IMRT significantly improved the tolerance to adjuvant chemoradiotherapy with compatible locoregional control compared with conventional Box-RT. However, longer follow-up and more patients are needed to confirm the benefits of IMRT.

Early Clinical Outcome With Concurrent Chemotherapy and Extended-Field, Intensity-Modulated Radiotherapy for Cervical Cancer

PURPOSE

To assess the early clinical outcomes with concurrent cisplatin and extended-field intensity-modulated radiotherapy (EF-IMRT) for carcinoma of the cervix.

METHODS AND MATERIALS

Thirty-six patients with Stage IB2-IVA cervical cancer treated with EF-IMRT were evaluated. The pelvic lymph nodes were involved in 19 patients, and of these 19 patients, 10 also had para-aortic nodal disease. The treatment volume included the cervix, uterus, parametria, presacral space, upper vagina, and pelvic, common iliac, and para-aortic nodes to the superior border of L1. Patients were assessed for acute toxicities according to the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 3.0. All late toxicities were scored with the Radiation Therapy Oncology Group late toxicity score.

RESULTS

All patients completed the prescribed course of EF-IMRT. All but 2 patients received brachytherapy. Median length of treatment was 53 days. The median follow-up was 18 months. Acute Grade > or = 3 gastrointestinal, genitourinary, and myelotoxicity were seen in 1, 1, and 10 patients, respectively. Thirty-four patients had complete response to treatment. Of these 34 patients, 11 developed recurrences. The first site of recurrence was in-field in 2 patients (pelvis in 1, pelvis and para-aortic in 1) and distant in 9 patients. The 2-year actuarial locoregional control, disease-free survival, overall survival, and Grade > or = 3 toxicity rates for the entire cohort were 80%, 51%, 65%, and 10%, respectively.

CONCLUSION

Extended-field IMRT with concurrent chemotherapy was tolerated well, with acceptable acute and early late toxicities. The locoregional control rate was good, with distant metastases being the predominant mode of failure. We are continuing to accrue a larger number of patients and longer follow-up data to further extend our initial observations with this approach.