Comparison of three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy in the treatment of cervical esophageal carcinoma

Obtaining organ-specific radiobiological parameters from clinical data for radiation therapy planning of head and neck cancers

Objective.Different radiation therapy (RT) strategies, e.g. conventional fractionation RT (CFRT), hypofractionation RT (HFRT), stereotactic body RT (SBRT), adaptive RT, and re-irradiation are often used to treat head and neck (HN) cancers. Combining and/or comparing these strategies requires calculating biological effective dose (BED). The purpose of this study is to develop a practical process to estimate organ-specific radiobiologic model parameters that may be used for BED calculations in individualized RT planning for HN cancers.Approach.Clinical dose constraint data for CFRT, HFRT and SBRT for 5 organs at risk (OARs) namely spinal cord, brainstem, brachial plexus, optic pathway, and esophagus obtained from literature were analyzed. These clinical data correspond to a particular endpoint. The linear-quadratic (LQ) and linear-quadratic-linear (LQ-L) models were used to fit these clinical data and extract relevant model parameters (alpha/beta ratio, gamma/alpha,dTand BED) from the iso-effective curve. The dose constraints in terms of equivalent physical dose in 2 Gy-fraction (EQD2) were calculated using the obtained parameters.Main results.The LQ-L and LQ models fitted clinical data well from the CFRT to SBRT with the LQ-L representing a better fit for most of the OARs. The alpha/beta values for LQ-L (LQ) were found to be 2.72 (2.11) Gy, 0.55 (0.30) Gy, 2.82 (2.90) Gy, 6.57 (3.86) Gy, 5.38 (4.71) Gy, and the dose constraint EQD2 were 55.91 (54.90) Gy, 57.35 (56.79) Gy, 57.54 (56.35) Gy, 60.13 (59.72) Gy and 65.66 (64.50) Gy for spinal cord, optic pathway, brainstem, brachial plexus, and esophagus, respectively. Additional two LQ-L parametersdTwere 5.24 Gy, 5.09 Gy, 7.00 Gy, 5.23 Gy, and 6.16 Gy, and gamma/alpha were 7.91, 34.02, 8.67, 5.62 and 4.95.Significance.A practical process was developed to extract organ-specific radiobiological model parameters from clinical data. The obtained parameters can be used for biologically based radiation planning such as calculating dose constraints of different fractionation regimens.

Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy Combined with Intracavitary Posterior Radiotherapy for the Treatment of Medium-Term and Advanced Cervical Cancer: Efficacy, Safety and Prognostic Factors

Objective

To explore the efficacy, safety, and prognostic factors of intensity modulated radiation therapy (IMRT) and three dimensional conformal radiation therapy (3D-CRT) combined with intracavitary posterior radiotherapy for medium-term and advanced cervical cancer.

Methods

Retrospectively analyze the clinical data of 104 patients with medium-term and advanced cervical cancer who were treated in the radiotherapy department of our hospital from September 2015 to March 2017. According to the different radiotherapy techniques, they were divided into the IMRT combined with intracavitary posterior radiotherapy group (n = 52) and the 3D-CRT combined with intracavitary posterior radiotherapy group (n = 52). Observe and compare the short-term efficacy, occurrence of adverse reactions and overall survival rate of the two groups. The clinicopathological characteristics of the survival group and the death group were compared, and univariate analysis and multiple logistic regression models were used to analyze the relationship between the clinicopathological characteristics and the patient’s prognosis.

Results

The total effective rate of IMRT combined with intracavitary posterior radiotherapy group was 96.15%, which was higher than that of 3D-CRT combined with intracavitary posterior radiotherapy group (88.46%), but the difference was not statistically significant (p > 0.05). The incidence of digestive system injury, thrombocytopenia, and radiation proctitis in the IMRT combined intracavitary posterior radiotherapy group was lower than that of the 3D-CRT combined intracavitary posterior radiotherapy group, and the differences were statistically significant (p < 0.05). The prognosis and survival of the two groups of patients were similar, and the difference was not statistically significant (p > 0.05). Pathological classification, clinical stage, and lymph node metastasis are independent influencing factors of 3-year prognosis in patients with medium-term and advanced cervical cancer (p < 0.05).

Conclusion

IMRT combined with intracavitary posterior radiotherapy is equivalent to 3D-CRT combined with intracavitary posterior radiotherapy, but it can reduce the incidence of adverse reactions in patients with medium-term and advanced cervical cancer, and has higher safety. Pathological typing, clinical staging, Lymph node metastasis were independent factor affecting the prognosis of patients. In clinical treatment, IMRT combined with intracavitary posterior radiotherapy is more recommended as a treatment plan for patients with medium-term and advanced cervical cancer.

Impact of Regional Lymph Node Irradiation on Reducing Lymph Node Recurrence in Esophageal Cancer Patients

BACKGROUND/AIM

To evaluate the preventive effects of regional lymph node irradiation on lymph node recurrence in esophageal cancer (EC).

PATIENTS AND METHODS

The study included 289 patients who received definitive radiotherapy for EC. The regional lymph node area of group 1 was determined as the area with the highest probability of lymph node metastasis and group 2 was determined as the area with the next highest probability of lymph node metastasis depending on the primary site of EC.

RESULTS

The patients in whom group 2 was completely included in the irradiated field had a significantly lower rate of recurrence of regional lymph node metastasis than those in whom group 2 was not or insufficiently included (p=0.0337). There was no significant difference in overall survival (p=0.4627) or disease-specific survival (p=0.6174) between the two groups.

CONCLUSION

Regional lymph node irradiation did not have survival-prolonging effects but significantly reduced regional lymph node recurrence.

Comparison between Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy for Their Effectiveness in Esophageal Cancer Treatment: A Retrospective Single Institution Study

Although a large number of influential studies that have been conducted worldwide on locally advanced esophageal cancer (EC) have employed the treatment modality of three-dimensional conformal radiotherapy (3D-CRT), an advanced as well as highly conformal technology known as intensity-modulated radiotherapy (IMRT) has attracted increasing attention from the radiotherapy research community. This is because of the clear advantages of IMRT, including decrease in radiation dose that reaches critical cardiopulmonary organs. These two treatment modalities need to be investigated with regard to their effect on local control rate and patient survival. In addition, related clinical factors also need to be explored. Data from a total of 431 patients with locally advanced EC, who underwent radiation therapy between January 1, 2010 and December 31, 2013, were included in the present study. Two hundred and ninety-three patients received 3D-CRT, while 138 patients received IMRT. We constructed propensity score matches to make the two groups be comparable (136 patients in 3D-CRT group and 138 patients in IMRT group. Kaplan–Meier analysis was conducted to evaluate the endpoint of overall survival (OS). A Cox proportional hazards model was employed to analyze the relationship between the associated factors and the outcomes via univariate and multivariate approaches. The mean follow-up period was 36.2 months, and the median follow-up period was 23 months. For the IMRT group, the median OS was 31 months, and the 1-, 3-, and 5-year OS rates were 70.3%, 50.0%, and 42.8%, respectively, while for the 3D-CRT group, the median OS was 22 months, and the 1-, 3-, and 5-year OS rates were 63.2%, 41.0%, and 35.4%, respectively (p < 0.05). The univariate analysis revealed that quit drinking, chemotherapy, and concurrent chemotherapy were significant risk factors for the prognosis of EC (p < 0.05), as well as the radiation therapy technique used (p=0.052). The multivariate analysis indicated that chemotherapy and quit drinking were independent predictive factors for OS. OS is found to be significantly better in the IMRT group, compared with that of the 3D-CRT group. Even though these outcomes need further validation, IMRT should be considered preferentially as a therapeutic option for EC, in combination with chemotherapy and persuading patients to quit drinking.

Salvage treatment for lymph node recurrence after radical resection of esophageal squamous cell carcinoma

Background

Patients with regional lymph node recurrence after radical resection of esophageal cancer have poor therapeutic outcomes. Currently, there is no standard treatment for regional lymph node recurrence, and its prognostic risk factors are not well-understood. This study retrospectively analyzed 83 patients with postoperative regional lymph node recurrence after radical resection of esophageal squamous cell carcinoma. The aim was to evaluate the clinical efficacy and prognostic factors of salvage radiotherapy with or without chemotherapy in these patients.

Methods

The survival and prognostic factors of 83 patients with esophageal squamous cell carcinoma with regional lymph node recurrence after radical surgery were retrospectively analyzed. All patients underwent radiotherapy, of which 74 patients received volumetric modulated arc therapy (VMAT), 9 patients received three-dimensional conformal radiation therapy (3DCRT), administered using a conventional segmentation protocol with a dose distribution range of 50.4–66.2Gy (median dose of 60Gy). In total, 41 patients received radiotherapy alone, 42 received radiotherapy combined with chemotherapy, and the concurrent chemotherapy regimen was mainly composed of either platinum or fluorouracil monotherapy, except for 4 patients who were given 5-fluorouracil plus platinum (FP) or paclitaxel plus platinum (TP).

Results

The median follow-up time was 24 (range, 9–75) months. The overall survival (OS) rates at 1 year, 2 years, 3 years, and 5 years were 83.0, 57.1, 40.1, and 35.1%, respectively. The median overall survival (OS) time was 18 (range, 5–75) months. The 3-year survival rate was 47.5% in patients with radiation alone and 41.9% in patients receiving concurrent chemoradiotherapy(p = 0.570), while the response rate (CR + PR) in those two groups was 73.2 and 91.4%, respectively. By multivariate analysis of OS, age (worse in younger patients, p = 0.034) was found to be significantly associated with disease prognosis. The commonly toxicities were esophagitis, neutropenia and anemia. 18% patients experienced grade 3 toxicity and no treatment-related death occurred.

Conclusions

These results of this retrospective analysis suggest that radiotherapy with or without chemotherapy is an effective and feasible salvage treatment for lymph node recurrence after radical resection of esophageal squamous cell carcinoma.

The radiation dose tolerance of the brachial plexus: A systematic review and meta-analysis

PURPOSE

We performed a systematic review and meta-analysis of studies reporting the incidence of radiation induced brachial plexopathy (RIBP) and the associated radiotherapy doses to this structure.

METHODS

Databases were queried without language restriction for cohort studies reporting RIBP incidence and associated brachial plexus dose maximum dose (bpDmax). Studies specifying RIBP relative risk (RR) effect size were selected for meta-analysis. RRs for RIBP from each study were converted to a regression coefficient (β) and standard error corresponding to a continuous representation of bpDmax. The adjusted β from individual studies were combined using a random effects model and weighted by inverse variance (1/SE2). The trim and fill approach was used to assess publication bias.

RESULTS

We identified 25 studies that included 37 unique patient cohorts eligible for analysis. Seventeen cohorts experienced an RIBP incidence ≤5%, of which 6 cohorts exceeded conventional plexus constraints of 60 Gy for bpDmax. Five of the 6 cohorts were simulated with 3D-CT techniques. Meta-analysis of eligible studies demonstrated a significant increase in RIBP risk for each Gy increase in bpDmax (RR, 1.11; 95% CI 1.07-1.15). Results remained significant after adjustment for publication bias and when sensitivity analysis was performed.

CONCLUSIONS

Our results suggest that current brachial plexus constraints of 60-66 Gy are safe. Meta-analysis provides a log-linear model to quantify the association of brachial plexus dose and RIBP risk, and thus inform the therapeutic ratio for dose escalation. Further prospective studies reporting dosimetric data can better refine this model and inform brachial plexus constraint guidelines.

Intensity-Modulated Radiotherapy versus Three-Dimensional Conformal Radiotherapy in Definitive Chemoradiotherapy for Cervical Esophageal Squamous Cell Carcinoma: Comparison of Survival Outcomes and Toxicities

PURPOSE

The purpose of this study was to compare the survival and toxicities in cervical esophageal squamous cell carcinoma (CESCC) treated by concurrent chemoradiothrapy with either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) techniques.

Materials and Methods

A total of 112 consecutive CESCC patients were retrospectively reviewed. 3D-CRT and IMRT groups had been analyzed by propensity score matching method, with sex, age, Karnofsky performance status, induction chemotherapy, and tumor stage well matched. The Kaplan-Meier method and Cox proportional hazards model were used for overall survival (OS) and progression-free survival (PFS). Toxicities were compared between two groups by Fisher exact test.

RESULTS

With a median follow-up time of 34.9 months, the 3-year OS (p=0.927) and PFS (p=0.859) rate was 49.6% and 45.8% in 3D-CRT group, compared with 54.4% and 42.8% in IMRT group. The rates of grade ≥ 3 esophagitis, grade ≥ 2 pneumonitis, esophageal stricture, and hemorrhage were comparable between two groups, while the rate of tracheostomy dependence was much higher in IMRT group than 3D-CRT group (14.3% vs.1.8%, p=0.032). Radiotherapy technique (hazard ratio [HR], 0.09; 95% confidence interval [CI], 0.01 to 0.79) and pretreatment hoarseness (HR, 0.12; 95% CI 0.02 to 0.70) were independently prognostic of tracheostomy dependence.

CONCLUSION

No survival benefits had been observed while comparing IMRT versus 3D-CRT in CESCC patients. IMRT with fraction dose escalation and pretreatment hoarseness were considered to be associated with a higher risk for tracheostomy dependence. Radiation dose escalation beyond 60 Gy should be taken into account carefully when using IMRT with hypofractionated regimen.

Influence of 3D-CRT and conformal IMRT on thyroid function of patients with cervical and upper thoracic esophageal cancer and comparison of clinical efficacy

Clinical efficacy in patients with cervical and upper thoracic esophageal cancer was compared between three-dimensional conformal radiotherapy (3D-CRT) and conformal intensity-modulated radiotherapy (IMRT). Medical data of 120 esophageal cancer patients undergoing RT in the Radiology Department in Xiaogan Hospital Affiliated to Wuhan University of Science and Technology (Xiaogan, China) from March 2015 to March 2018 were retrospectively analyzed. Patients were divided into 3D-CRT group (treated with 3D-CRT, n=60) and IMRT group (treated with IMRT, n=60). The target conformal index (CI), PTV maximum dose (D_max), PTV D_min and PTV D_mean in both groups were observed. Changes in double-lung V5, double-lung V20, double-lung V30 and spinal cord D_max in both groups were also observed. The serum free triiodothyronine (FT3), free tetraiodothyronine (FT4) and thyroid-stimulating hormone (TSH) concentrations were detected via chemiluminescence assay. Moreover, the short-term efficacy and radiation injury were observed. CI in IMRT group was significantly higher than that in 3D-CRT group (P<0.001). The organ-at-risk dose parameter V20 in IMRT group was obviously lower than that in 3D-CRT group (P<0.001). Serum FT3 and FT4 concentrations in both groups before RT were significantly higher than those after RT (P<0.05), but the TSH concentration was significantly lower than that after RT (P<0.05). Serum FT3 and FT4 concentrations in IMRT group after RT were obviously higher than those in 3D-CRT group (P<0.05). The incidence rates of radiation esophagitis and radiation pneumonitis in IMRT group were remarkably lower than those in 3D-CRT group (P<0.05). IMRT can reduce the double-lung V20 in patients, improve the target conformal degree, better protect the normal tissues, cause less damage to thyroid function, and reduce radiation injury during and after RT of esophageal cancer.

Definitive chemoradiotherapy with docetaxel, cisplatin, and 5-fluorouracil (DCF-R) for advanced cervical esophageal cancer

BACKGROUND

Recently, definitive chemoradiotherapy (dCRT) has become one of the essential treatment strategies for esophageal squamous cell carcinoma (ESCC) and has been especially gaining prevalence for cervical ESCC to preserve the larynx. Our department recently introduced dCRT concomitant with docetaxel, cisplatin, and 5-fluorouracil (DCF-R) for treating advanced cervical ESCC. This study aims to assess the safety and outcomes of DCF-R in patients with advanced cervical ESCC.

METHODS

We retrospectively assessed 11 patients with advanced cervical ESCC (clinical stage: II-IV, including T4b and/or M1 lymph node) who received DCF-R as the first-line treatment between December 2010 and February 2015.

RESULTS

Our patient cohort comprised 8 males and 3 females (median age 68 years; range 54-76 years). The pretreatment clinical stage included stage II (1), stage III (7), and stage IV (3) cases [including 3 patients with T4b (2 trachea and 1 thyroid) and 3 patients with M1 lymph node]. We attained complete response (CR) in 10 patients and stable disease in 1 patient. Of 10 patients with CR, 5 experienced recurrence and 5 continued exhibiting CR. Furthermore, grade 3 or more adverse events included leucopenia (91%), neutropenia (91%), febrile neutropenia (45%), and pharyngeal pain (55%). While the 2-year overall survival rate was 72%, the 2-year recurrent-free survival rate was 64%, respectively.

CONCLUSIONS

DCF-R treatment for advanced cervical esophageal cancer could be completed by the careful administration; although a strong blood toxicity might occur, this treatment may provide the chance to obtain favorable prognosis with larynx preservation.

Efficacy of virtual block objects in reducing the lung dose in helical tomotherapy planning for cervical oesophageal cancer: a planning study

Background

Intensity-modulated radiotherapy is useful for cervical oesophageal carcinoma (CEC); however, increasing low-dose exposure to the lung may lead to radiation pneumonitis. Nevertheless, an irradiation technique that avoids the lungs has never been examined due to the high difficulty of dose optimization. In this study, we examined the efficacy of helical tomotherapy that can restrict beamlets passing virtual blocks during dose optimization computing (block plan) in reducing the lung dose.

Methods

Fifteen patients with CEC were analysed. The primary/nodal lesion and prophylactic nodal region with adequate margins were defined as the planning target volume (PTV)-60 Gy and PTV-48 Gy, respectively. Nineteen plans per patient were made and compared (total: 285 plans), including non-block and block plans with several shapes and sizes.

Results

The most appropriate block model was semi-circular, 8 cm outside of the tracheal bifurcation, with a significantly lower lung dose compared to that of non-block plans; the mean lung volumes receiving 5 Gy, 10 Gy, 20 Gy, and the mean lung dose were 31.3% vs. 48.0% (p <  0.001), 22.4% vs. 39.4% (p <  0.001), 13.2% vs. 16.0% (p = 0.028), and 7.1 Gy vs. 9.6 Gy (p <  0.001), respectively. Both the block and non-block plans were comparable in terms of the homogeneity and conformity indexes of PTV-60 Gy: 0.05 vs. 0.04 (p = 0.100) and 0.82 vs. 0.85 (p = 0.616), respectively. The maximum dose of the spinal cord planning risk volume increased slightly (49.4 Gy vs. 47.9 Gy, p = 0.002). There was no significant difference in the mean doses to the heart and the thyroid gland. Prolongation of the delivery time was less than 1 min (5.6 min vs. 4.9 min, p = 0.010).

Conclusions

The block plan for CEC could significantly reduce the lung dose, with acceptable increment in the spinal dose and a slightly prolonged delivery time.

Utilization of neoadjuvant intensity-modulated radiation therapy and proton beam therapy for esophageal cancer in the United States

Background

Randomized esophageal cancer (EC) trials have utilized two- or three-dimensional conformal radiotherapy (3DCRT). Advanced radiotherapy (RT) techniques [(ARTs): intensity-modulated radiotherapy (IMRT) and proton beam therapy (PBT)] may have benefits, but are relatively unproven. This is the first study to date evaluating utilization of ARTs versus 3DCRT in the trimodality setting in the United States.

Methods

The National Cancer Data Base (NCDB) was queried (2004-2013) for newly-diagnosed cT1b-T4bN0/N+M0 EC receiving neoadjuvant CRT followed by esophagectomy. The primary objective was to assess temporal trends, with multivariable logistic regression analysis assessing factors predictive of receiving ARTs. Secondarily, Kaplan-Meier analysis evaluated overall survival (OS), Cox proportional hazards modeling determined variables associated with OS, and postoperative complications were compared between cohorts.

Results

Altogether, 3,138 patients met criteria; 1,398 (45%) received 3DCRT, and 1,740 (55%) received ARTs (99% IMRT, 1% PBT). Temporally, utilization of ARTs is steadily rising in the United States, from 20% in 2004 to 69% in 2013, corresponding with a progressive decrease in utilization of 3DCRT. ARTs were more often delivered with advancing age, squamous cell histology, N2+ disease, and at academic centers (P<0.05 for all). Centers in the Southwest were more likely to use ARTs, and those in the Midwest least likely (P<0.05 for both). As expected, there were no OS differences (P=0.8477); there were also no differences in postoperative events (P>0.05 for all). Treatment at an academic center independently correlated with improved OS (P<0.001).

Conclusions

Utilization of ARTs (IMRT in the vast majority) is steadily rising in the United States; 3DCRT is now used in a minority of patients. This has implications for payers and insurance coverage. ART use is impacted by not only age and disease factors, but also regional and facility differences. Treatment at an academic facility independently correlated with higher survival, which has implications for patient counseling.

Novel use of proton beam therapy for neoadjuvant treatment of radiation-associated squamous cell carcinoma of the esophagus

Secondary esophageal cancers from prior thoracic radiation therapy are rare but challenging cases to deliver standard combined modality therapy as part of a curative approach. In patients with prior exposure to cardiopulmonary-toxic chemotherapy or radiotherapy, management requires meticulous multidisciplinary evaluation given the morbidity associated with surgery in the previously irradiated thorax and re-irradiation of the spinal cord, heart, and lungs. Oftentimes, suboptimal treatment regimens, either with compromised radiation coverage, attenuated chemotherapy doses, or exclusion of surgery, are required to avoid significant toxicity. The physical properties inherent to protons allow for optimal coverage of tumor while achieving remarkably low dose to surrounding normal tissue compared to standard photon treatment. Proton therapy has been studied across various disease sites and may facilitate treatment intensification for radiation-associated esophageal tumors. While no comparative studies have evaluated the efficacy and safety of protons versus photons for esophageal cancer, three cases of radiation-associated esophageal cancer presented in this series are exemplary to highlight the benefit of protons in this unique clinical circumstance. The technical considerations in planning, including passively scattered versus pencil-beam scanning technique, as well as the clinical course and tolerance to treatment, are discussed, which may guide consideration of this advanced treatment modality in this disease site.

Long-term outcome of definitive radiotherapy for cervical esophageal squamous cell carcinoma

BACKGROUND

The aim of this study was to identify the long-term clinical outcome of definitive radiotherapy using three-dimensional conformal radiotherapy (3DCRT) for cervical esophageal squamous cell carcinoma (CESCC).

METHODS

We retrospectively reviewed the medical records of 30 patients with CESCC [clinical stage I/II/III/IV(M1LYM); 3/2/12/13] (TNM 7th edition) who underwent definitive radiotherapy using 3DCRT between 2000 and 2014 in our institution. The median prescribed dose for the gross tumor and metastatic lymph nodes was 60 Gy. Twenty-six patients underwent elective nodal irradiation for the neck node levels III, IV, and VI and for upper mediastinal lymph nodes with a median dose of 40 Gy. Twenty-six patients underwent concurrent chemotherapy. Initial disease progression sites, locoregional control (LRC) rate, overall survival (OS) rate, and toxicities were retrospectively evaluated. A univariate analysis was performed to identify prognostic factors.

RESULTS

With a median follow-up of 110 months, the 5- and 10-year LRC rates were 43.7% and 37.4%, respectively. The 5- and 10-year OS rates were 48.3% and 40.2%, respectively. Locoregional, distant and both area accounted for 83%, 6% and 11% of the initial progression sites. Unresectable status and M1LYM were significantly associated with poor LRC (p < 0.05) and OS (p < 0.05). Grade 3 acute non-hematological toxicity occurred in 13.3% of patients. During the follow-up, patients without any disease progression did not need a permanent gastrostomy tube or tracheostomy. Late toxicity events, including hypothyroidism and cardiovascular disease, were observed; 5- and 10-year cumulative incidence rates of grade 2 hypothyroidism and ≥grade 3 cardiovascular disease were 31.6% and 62.5%, and 17.5% and 21.3%, respectively.

CONCLUSIONS

Definitive radiotherapy yields a cure for patients with CESCC while preserving their laryngopharyngeal function. The poor LRC rate in the advanced stage needs to be overcome for a better prognosis. As the incidence of radiation-induced hypothyroidism and cardiovascular disease was not low, long-term survivors should be followed up for these symptoms.