Three-dimensional conformal radiation therapy for esophageal squamous cell carcinoma: is elective nodal irradiation necessary?

PURPOSE

To evaluate the local control, survival, and toxicity associated with three-dimensional conformal radiotherapy (3D-CRT) for squamous cell carcinoma (SCC) of the esophagus, to determine the appropriate target volumes, and to determine whether elective nodal irradiation is necessary in these patients.

METHODS AND MATERIALS

A prospective study of 3D-CRT was undertaken in patients with esophageal SCC without distant metastases. Patients received 68.4 Gy in 41 fractions over 44 days using late-course accelerated hyperfractionated 3D-CRT. Only the primary tumor and positive lymph nodes were irradiated. Isolated out-of-field regional nodal recurrence was defined as a recurrence in an initially uninvolved regional lymph node.

RESULTS

All 53 patients who made up the study population tolerated the irradiation well. No acute or late Grade 4 or 5 toxicity was observed. The median survival time was 30 months (95% confidence interval, 17.7-41.8). The overall survival rate at 1, 2, and 3 years was 77%, 56%, and 41%, respectively. The local control rate at 1, 2, and 3 years was 83%, 74%, and 62%, respectively. Thirty-nine of the 53 patients (74%) showed treatment failure. Seventeen of the 39 (44%) developed an in-field recurrence, 18 (46%) distant metastasis with or without regional failure, and 3 (8%) an isolated out-of-field nodal recurrence only. One patient died of disease in an unknown location.

CONCLUSIONS

In patients treated with 3D-CRT for esophageal SCC, the omission of elective nodal irradiation was not associated with a significant amount of failure in lymph node regions not included in the planning target volume. Local failure and distant metastases remained the predominant problems.

Three-dimensional conformal radiotherapy for locoregionally recurrent lung carcinoma after external beam irradiation: a prospective phase I-II clinical trial

OBJECTIVES

To observe in a clinical trial the feasibility, tolerance, and efficacy of reirradiation by three-dimensional conformal radiotherapy (3D-CRT) for locoregionally recurrent lung carcinoma after external beam radiotherapy (EBRT).

MATERIALS AND METHODS

Between June 1999 and March 2001, 23 lung carcinoma patients with locoregional recurrence after EBRT were enrolled in this study. Of the 23 patients, 21 were men and 2 were women (median age 68 years, range 43-79). At the first course of RT, 9 patients had squamous cell carcinoma, 7 adenocarcinoma, and 7 small cell carcinoma. The interval between the first course of RT and recurrence varied from 6 to 42 months (median 13). The median dose of the first course of RT was 66 Gy (range 30-78). Reirradiation was carried out using 3D-CRT and only covered the radiographic lesions. The median dose of reirradiation was 51 Gy (range 46-60), which was delivered by a conventionally fractionated schedule (i.e., 1.8-2.0 Gy/fraction, 5 fractions/wk). The toxicity was assessed according to the Radiation Therapy Oncology Group criteria.

RESULTS

The median follow-up time was 15 months (range 2-37). Acute radiation esophagitis occurred in 9% of patients (Grade 1-2). Acute radiation pneumonitis developed in 22% of patients (Grade 1-2). No cases of acute Grade 3 or greater toxicity had been recorded at last follow-up. Pulmonary fibrosis was observed in 26% of patients (Grade 2-3); no other severe late complications have been observed. The 1- and 2-year survival rate was 59% and 21%, respectively. The locoregional progression-free rate at 1 and 2 years was 51% and 42%, respectively.

CONCLUSIONS

Reirradiation using 3D-CRT was tolerated by this group of recurrent lung carcinoma patients without severe complications. The 2-year outcome was encouraging. Reirradiation with 3D-CRT can be considered an option for the management of locoregionally recurrent lung carcinoma.

CK19 mRNA expression measured by reverse-transcription polymerase chain reaction (RT-PCR) in the peripheral blood of patients with non-small cell lung cancer treated by chemo-radiation: an independent prognostic factor

PURPOSE

To investigate the prognostic significance of circulating cancer cells in peripheral blood (PB) of patients with non-small cell lung cancer (NSCLC) treated by chemo-radiation with curative intent.

METHODS

Cytokeratin-19 (CK19) mRNA was measured by nested reverse-transcription polymerase chain reaction (RT-PCR) in PB from 67 NSCLC patients before and after chemo-radiation. The measurements of CK19 mRNA were compared to the outcome of therapy to evaluate its significance of prognoses.

RESULTS

The sensitivity and specificity of CK19 RT-PCR was 10(-7) and 96.7%, respectively. The positive rate of CK19 mRNA in PB before chemo-radiation was correlated only to N stage (p=0.014). In contrast, it was more closely correlated to histological types (adenocarcinoma versus non-adenocarcinoma) (p=0.019), weight loss (p=0.010), KPS status (p=0.027) and N stage (p=0.032) after chemo-radiation. CK19 status in PB before chemo-radiation did not permit predictions of overall survival (p=0.375) and progression-free survival (p=0.573). However, the patients with CK19 mRNA expression in PB after treatments had poorer overall survival (p<0.001) and progression-free survival (p<0.001) as compared to those with negative CK19 mRNA expression. The worst survivals were seen in patients with persistently positive CK19 mRNA expression both before and after treatments. Multivariate analyses demonstrated that the positivity of CK19 mRNA after chemo-radiation was an independent unfavorable prognostic factor for both overall survival and progression-free survival (p<0.001 and <0.001).

CONCLUSION

Only after chemo-radiation could the measurement of CK19 mRNA in PB predict the prognoses of NSCLC. Patients with the positive CK19 mRNA had shorter survival compared to the negative patients.

PET CT thresholds for radiotherapy target definition in non-small-cell lung cancer: how close are we to the pathologic findings?

PURPOSE

Optimal target delineation threshold values for positron emission tomography (PET) and computed tomography (CT) radiotherapy planning is controversial. In this present study, different PET CT threshold values were used for target delineation and then compared pathologically.

METHODS AND MATERIALS

A total of 31 non-small-cell lung cancer patients underwent PET CT before surgery. The maximal diameter (MD) of the pathologic primary tumor was obtained. The CT-based gross tumor volumes (GTV(CT)) were delineated for CT window-level thresholds at 1,600 and -300 Hounsfield units (HU) (GTV(CT1)); 1,600 and -400 (GTV(CT2)); 1,600 and -450 HU (GTV(CT3)); 1,600 and -600 HU (GTV(CT4)); 1,200 and -700 HU (GTV(CT5)); 900 and -450 HU (GTV(CT6)); and 700 and -450 HU (GTV(CT7)). The PET-based GTVs (GTV(PET)) were autocontoured at 20% (GTV(20)), 30% (GTV(30)), 40% (GTV(40)), 45% (GTV(45)), 50% (GTV(50)), and 55% (GTV(55)) of the maximal intensity level. The MD of each image-based GTV in three-dimensional orientation was determined. The MD of the GTV(PET) and GTV(CT) were compared with the pathologically determined MD.

RESULTS

The median MD of the GTV(CT) changed from 2.89 (GTV(CT2)) to 4.46 (GTV(CT7)) as the CT thresholds were varied. The correlation coefficient of the GTV(CT) compared with the pathologically determined MD ranged from 0.76 to 0.87. The correlation coefficient of the GTV(CT1) was the best (r=0.87). The median MD of GTV(PET) changed from 5.72 cm to 2.67 cm as the PET thresholds increased. The correlation coefficient of the GTV(PET) compared with the pathologic finding ranged from 0.51 to 0.77. The correlation coefficient of GTV(50) was the best (r=0.77).

CONCLUSION

Compared with the MD of GTV(PET), the MD of GTV(CT) had better correlation with the pathologic MD. The GTV(CT1) and GTV(50) had the best correlation with the pathologic results.

Patterns of local-regional failure in completely resected stage IIIA(N2) non-small cell lung cancer cases: implications for postoperative radiation therapy clinical target volume design

PURPOSE

To analyze patterns of local-regional failure (LRF) for completely resected stage IIIA(N2) non-small cell lung cancer (NSCLC) patients treated in our hospital and to propose a clinical target volume (CTV) for postoperative radiation therapy (PORT) in these patients.

METHODS AND MATERIALS

From 2005 to 2011, consecutive patients with pT1-3N2 NSCLC who underwent complete resection in our hospital but who did not receive PORT were identified. The patterns of first LRF were assessed and evaluated as to whether these areas would be encompassed by our proposed PORT CTV.

RESULTS

With a median follow-up of 24 months, 173 of 250 patients (69.2%) experienced disease recurrence. Of the 54 patients with LRF as the first event, 48 (89%) had recurrence within the proposed PORT CTV, and 6 (11%) had failures occurring both within and outside the proposed CTV (all of which occurred in patients with right-lung cancer). Ninety-three percent of failure sites (104 of 112) would have been contained within the proposed PORT CTV. For left-sided lung cancer, the most common lymph node station failure site was 4R, followed by 7, 4L, 6, 10L, and 5. For right-sided lung cancer, the most common site was station 2R, followed by 10R, 4R, and 7.

CONCLUSIONS

LRF following complete surgery was an important and potentially preventable pattern of failure in stage IIIA(N2) patients. Ipsilateral superior mediastinal recurrences dominated for right-sided tumors, whereas left-sided tumors frequently involved the bilateral superior mediastinum. Most of the LRF sites would have been covered by the proposed PORT CTV. A prospective investigation of patterns of failure after PORT (following our proposed CTV delineation guideline) is presently underway and will be reported in a separate analysis.

Simultaneous integrated boost intensity-modulated radiotherapy in esophageal carcinoma: early results of a phase II study

PURPOSE

The safety and efficacy of using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for patients with esophageal squamous cell carcinoma were evaluated in a single-institution phase II setting.

METHODS AND MATERIALS

Between June 2007 and October 2009, 45 patients underwent concurrent chemoradiotherapy (n = 27) or radiotherapy alone (n = 18). Two planning target volumes (PTV) were defined for the SIB: PTVC and PTVG, with prescribed doses of 50.4 Gy to the PTVC (1.8 Gy/fraction) and 63 Gy to the PTVG (2.25 Gy/fraction), both given in 28 fractions.

RESULTS

At a median follow-up interval of 20.3 months, the 3-year overall survival (OS) and progression-free survival (PFS) rates were 42.2 and 40.7 %, respectively. The median overall survival time was 21 months; locoregional control rates were 83.3 % at 1 year and 67.5 % at 3 years. According to CTCAE (version 3.0) criteria, none of the patients developed grade 4-5 toxicity. The most common grade 2 and 3 radiation-related toxicity was radiation esophagitis, occurring in 64 % of all patients (but only 13 % as grade 3). No patient developed grade > 2 pulmonary complications.

CONCLUSION

SIB-IMRT is a feasible therapeutic approach for esophageal carcinoma patients and provides encouraging locoregional control with a low toxicity profile. Further investigations should focus on dose escalation and optimization of the combination with systemic therapies.

A phase II trial of accelerated hypofractionated three-dimensional conformal radiation therapy in locally advanced non-small cell lung cancer

PURPOSE

The aim of this study is to evaluate the safety and efficacy of accelerated hypofractionated radiotherapy (HypoRT) combined with sequential chemotherapy in locally advanced non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

A total of 34 patients with stage III NSCLC were enrolled. All patients received accelerated HypoRT (initially 50Gy/20 fractions, then a fraction dose of 3Gy) using three-dimensional conformal radiation therapy (3D-CRT), omitting elective nodal irradiation (ENI), to a total dose of 65-68Gy. All patients received two cycles of induction chemotherapy; 1-2 cycles of consolidation chemotherapy were given to 31 patients. The primary outcome measure was a profile of radiation toxicity. The secondary endpoints included overall survival (OS), progression-free survival (PFS), locoregional PFS (LR-PFS) and the pattern of initial failure.

RESULTS

Radiation toxicity was minimal. The median and 3-year OS, PFS were 19.0 months, 32.1%; 10.0 months, 29.8%, respectively. The 1-, 2-, and 3-year LR-PFS were 69.6%, 60.9% and 60.9%, respectively. No patient experienced isolated elective nodal failure as the first site of failure.

CONCLUSION

This study suggests that accelerated HypoRT using 3D-CRT omitting ENI can be used in combination with sequential chemotherapy in locally advanced NSCLC.

Three-dimensional conformal radiation therapy for non-small-cell lung cancer: a phase I/II dose escalation clinical trial

PURPOSE

A prospective Phase I/II dose escalation study was conducted to determine the maximum tolerated dose (MTD) in three-dimensional conformal radiation therapy (3D-CRT) for non-small-cell lung cancer (NSCLC).

MATERIALS AND METHODS

MTD would be reached via a dose escalation study. After 42 Gy/21 fractions, 4.2 weeks by conventional fractionated irradiation through anteroposterior/posteroanterior fields, the 3D-CRT technique was used as boost. The planned total dose escalation depended on lung volume irradiated. According to the percentage of lung volume receiving >20 Gy, the patients were divided into three subgroups (i.e., <25%, 25%-37%, and >37%). The scheduled dose escalation began with 69 Gy and continued to 78 Gy. The boost doses were delivered at 3 Gy per fraction, once per day, five fractions per week. Each dose level includes 5 patients. Besides radiotherapy, all patients received neoadjuvant and adjuvant chemotherapy with MVP regimen (Mitomycin, Vindesine, cis-platium). The criterion for stopping further dose escalation was > or =20% of patients with > or =RTOG Grade 3 radiation pneumonitis.

RESULTS

Between June 1999 and February 2001, 50 patients had been enrolled in this study, including 4 with Stage II disease, 31 with Stage IIIa disease, and 15 with Stage IIIb disease. The dose escalation plan has been completed. All subgroups reached the highest predetermined dose levels (i.e., 78 Gy for the <25% subgroup, 78 Gy for the 25-37% subgroup, and 75 Gy for the >37% subgroup). Although none of the subgroups developed more than 20% of >/=Grade 3 acute pneumonitis, dose escalation was terminated because long-term follow-up was needed to observe late complications. Median follow-up time (MFT) for the entire group was 18 months (6-37 months). The most common acute complication was esophagitis in 56% of patients with RTOG Grade 1-2, and in 4% with Grade 3. Acute radiation pneumonitis developed in 36% of patients with RTOG Grade 1-2. Only 1 patient had Grade 3 pneumonitis, which was in the 25-37% subgroup at 75 Gy. The hematopoietic toxicity appeared in 58% of patients with Grade 1-2, and 8% with Grade 3. As to late complications, only 30% of patients developed pulmonary fibrosis of RTOG Grade 1-2. The median survival time for the entire group was 18 months. Two-year overall survival, locoregional progression-free rate, and distant metastasis rate were 44%, 40%, and 41%, respectively.

CONCLUSIONS

Although MFT was 18 months, it had not yet been declared because a longer follow-up was needed to observe the late complications. The 2-year overall survival of 44% was very encouraging and implied that 3D-CRT combined with chemotherapy would improve the outcome for locally advanced NSCLC.

Phase 2 study of accelerated hypofractionated thoracic radiation therapy and concurrent chemotherapy in patients with limited-stage small-cell lung cancer

PURPOSE

To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting.

METHODS AND MATERIALS

Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 to 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate.

RESULTS

Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation.

CONCLUSION

Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.

Loss of neuronal protein expression in mouse hippocampus after irradiation

The effects of radiation on neurons are incompletely characterized. We evaluated changes in the expression of neuronal nuclear and other proteins in the mouse hippocampus after 17-Gy whole-brain irradiation. Expression of neuronal nuclei (NeuN), neuron-specific enolas, prospero-related homeobox 1 (Prox1), calbindin D28k, and synaptophysin 1 in the CA1, CA3, and dentate gyrus of the hippocampus was determined by immunohistochemistry; neuronal numbers were estimated by design-based stereology. At 7 days after irradiation, there was a marked reduction of NeuN neurons in CA3. Stereologic estimates confirmed a significant reduction in NeuN neurons in CA3 at 7 days, in the dentate gyrus at 7 days, 3 weeks and 2 months, and in CA1 at 2 months compared with controls; neuron-specific enolase and prospero-related homeobox 1-positive neurons in the CA3 subregion were also decreased at 7 days. The numbers of granule and pyramidal cells identified by 4'6-diamidino-2-phenylindole nuclear staining, however, remained unchanged, and there were no changes in calbindin D28k or synaptophysin 1 immunoreactivity after irradiation. We conclude that irradiation may result in a temporary loss of neuronal protein expression in mouse hippocampus. These changes do not necessarily indicate loss of neurons and indicate the need for caution regarding the use of phenotypic markers such as NeuN to estimate changes in neuronal numbers after irradiation.

Autocontouring and manual contouring: which is the better method for target delineation using 18F-FDG PET/CT in non-small cell lung cancer?

Previously, we showed that a CT window and level setting of 1,600 and -300 Hounsfield units, respectively, and autocontouring using an (18)F-FDG PET 50% intensity level correlated best with pathologic results. The aim of this study was to compare this autocontouring with manual contouring, to determine which method is better.

METHODS

Seventeen patients with non-small cell lung cancer underwent (18)F-FDG PET/CT before surgery. The maximum diameter on pathologic examination was determined. Seven sets of gross tumor volumes (GTVs) were defined. The first set (GTV(CT)) was contoured manually using only CT information. The second set (GTV(Auto)) was autocontoured using a 50% intensity level for (18)F-FDG PET images. The third set (GTV(Manual)) was manually contoured using a visual method on PET images. The other 4 sets combined CT and (18)F-FDG PET images fused to one another to become composite volumes: GTV(CT+Auto), GTV(CT+Manual), GTV(CT-Auto), and GTV(CT-Manual). To quantitate the degree to which CT and (18)F-FDG PET defined the same region of interest, a matching index was calculated for each case. The maximum diameter of GTV was compared with the maximum diameter on pathologic examination.

RESULTS

The median GTV(CT), GTV(Auto), GTV(Manual), GTV(CT+Auto), GTV(CT+Manual), GTV(CT-Auto), and GTV(CT-Manual) were 6.96, 2.42, 4.37, 7.46, 10.17, 2.21, and 3.38 cm(3), respectively. The median matching indexes of GTV(CT) versus GTV(CT+Auto), GTV(Auto) versus GTV(CT+Auto), GTV(CT) versus GTV(CT+Manual), and GTV(Manual) versus GTV(CT+Manual) were 0.86, 0.65, 0.88, and 0.81, respectively. Compared with the maximum diameter on pathologic examination, the correlations of GTV(CT), GTV(Auto), GTV(Manual), GTV(CT+Auto), and GTV(CT+Manual) were 0.87, 0.83, 0.93, 0.86, and 0.94, respectively.

CONCLUSION

The matching index was higher for manual contouring than for autocontouring using a 50% intensity level on (18)F-FDG PET images. When using a 50% intensity level to contour the target of non-small cell lung cancer, one should also consider using manual contouring of (18)F-FDG PET to check for any missed disease.

Eliminating Radiation Resistance of Non-Small Cell Lung Cancer by Dihydroartemisinin Through Abrogating Immunity Escaping and Promoting Radiation Sensitivity by Inhibiting PD-L1 Expression

Radiation resistance is linked to immune escaping and radiation sensitivity. In this study, we found that the PD-L1 expressions of non-killed tumor cells in NSCLC were enhanced after radiotherapy, and dihydroartemisinin (DHA) could synergistically enhance the antitumor effect of radiotherapy in NSCLC. A total of 48 NSCLC patients with sufficient tumor tissues for further analyses were enrolled. The PD-L1 expressions of NSCLC were evaluated by immunohistochemistry. Cell apoptosis was measured by flow cytometry, and the relationship between the PD-L1 expression and radiation resistance was investigated in patient specimens, xenograft model, and cell lines. First, the results indicate that the PD-L1 expression of NSCLC was positively related with the radiation resistance. Second, we found that DHA could eliminate the radiation resistance and synergistically enhance the antitumor effect of radiotherapy in the NSCLC cells lines and xenograft model. Finally, mechanistically, DHA could inhibit the PD-L1 expression to avoid immune escaping by inhibiting TGF-β, PI3K/Akt, and STAT3 signaling pathways. In addition, DHA could activate TRIM21 and regulate the EMT-related proteins by inhibiting the PD-L1 so as to enhance the radiation sensitivity and eliminate radiation resistance to NSCLC. Collectively, this study established a basis for the rational design of integrated radiotherapy and DHA for the treatment of NSCLC.

Role of intercellular adhesion molecule-1 in radiation-induced brain injury

PURPOSE

To determine the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of brain injury after irradiation (IR).

METHODS AND MATERIALS

We assessed the expression of ICAM-1 in mouse brain after cranial IR and determined the histopathologic and behavioral changes in mice that were either wildtype (+/+) or knockout (-/-) of the ICAM-1 gene after IR.

RESULTS

There was an early dose-dependent increase in ICAM-1 mRNA and protein expression after IR. Increased ICAM-1 immunoreactivity was observed in endothelia and glia of ICAM-1+/+ mice up to 8 months after IR. ICAM-1-/- mice showed no expression. ICAM-1+/+ and ICAM-1-/- mice showed similar vascular abnormalities at 2 months after 10-17 Gy, and there was evidence for demyelination and inhibition of hippocampal neurogenesis at 8 months after 10 Gy. After 10 Gy, irradiated ICAM-1+/+ and ICAM-1-/- mice showed similar behavioral changes at 2-6 months in open field, light-dark chamber, and T-maze compared with age-matched genotype controls.

CONCLUSION

There is early and late upregulation of ICAM-1 in the vasculature and glia of mouse brain after IR. ICAM-1, however, does not have a causative role in the histopathologic injury and behavioral dysfunction after moderate single doses of cranial IR.

Electroacupuncture Improves Cognitive Function and Hippocampal Neurogenesis after Brain Irradiation

Cognitive impairments after brain irradiation seriously affect quality of life for patients, and there is currently no effective treatment. In this study using an irradiated rat model, the role of electroacupuncture was investigated for treatment of radiation-induced brain injury. Animals received 10 Gy exposure to the entire brain, and electroacupuncture was administered 3 days before irradiation as well as up to 2 weeks postirradiation. Behavioral tests were performed one month postirradiation, and rats were then sacrificed for histology or molecular studies. Electroacupuncture markedly improved animal performance in the novel place recognition test. In the emotion test, electroacupuncture reduced defecation during the open-field test, and latency to consumption of food in the novelty suppressed feeding test. Brain irradiation inhibited the generation of immature neurons, but did not cause neural stem cell loss. Electroacupuncture partially restored hippocampal neurogenesis. Electroacupuncture decreased the amount of activated microglia and increased resting microglia in the hippocampus after irradiation. In addition, electroacupuncture promoted mRNA and protein expression of brain-derived neurotrophic factor (BDNF) in the hippocampus. In conclusion, electroacupuncture could improve cognitive function and hippocampal neurogenesis after irradiation, and the protective effect of electroacupuncture was associated with the modulation of microglia and upregulation of BDNF in the hippocampus.

Three-dimensional conformal radiation therapy for squamous cell carcinoma of the esophagus: a prospective phase I/II study

PURPOSE

A prospective phase I-II study was conducted to determine the tolerance and local control rate of three-dimensional conformal radiotherapy (3-DCRT) for esophageal squamous cell carcinoma (SCC).

METHODS AND MATERIALS

Thirty patients underwent 3-DCRT for thoracic esophageal SCC. PTV1 composed of a 1.2-1.5 cm margin lateral around GTV and 3.0 cm margin superior/inferior of GTV. PTV2 encompassed GTV with a margin of 0.5-0.7 cm. The dose for PTV1 was 50 Gy in 2 Gy daily fractions; PTV2 received a boost of 16 Gy in 2 Gy daily fractions to a total dose of 66 Gy.

RESULTS

Median follow-up time was 18 months. The most common acute toxicity was esophagitis in 63% of patients with RTOG grades 1-2, and in 3% with grade 3. RTOG grades 1-2 radiation pneumonitis developed in 27% of patients. One patient developed pulmonary fibrosis RTOG grade 2 and another patient experienced grade 3 pulmonary fibrosis. Two patients developed mild esophageal stricture requiring dilatation. Two-year overall survival, local disease progression-free rate, and distant metastasis-free rate were 69%, 36% and 56%, respectively.

CONCLUSIONS

Although 3-DCRT to 66 Gy for esophageal SCC was well tolerated, the local control was disappointing. The result supports the use of chemoradiation as the standard care for esophageal SCC.

Hypo- or conventionally fractionated radiotherapy combined with chemotherapy in patients with limited stage small cell lung cancer

BACKGROUND

Previous data from our institution showed that hypofractionated thoracic radiotherapy (HypoTRT) with concurrent etoposide/platinum chemotherapy yielded favorable survival in patients with limited-stage small cell lung cancer (LS-SCLC). The present study retrospectively compared the survival outcomes, failure patterns and toxicities between groups of LS-SCLC patients treated with conventionally fractionated thoracic radiotherapy (ConvTRT) or HypoTRT combined with chemotherapy.

METHODS

Medical records of LS-SCLC patients between January 2010 and December 2013 at Fudan University Shanghai Cancer Center were retrospectively reviewed. All patients treated with chemotherapy and ConvTRT (2 Gy per fraction daily, DT ≥ 56 Gy) or HypoTRT (2.5 Gy per fraction daily, DT = 55 Gy) were eligible for analysis. Progression-free survival (PFS) and overall survival (OS) were generated for different populations using the Kaplan-Meier method and compared using the log-rank test. Comparisons of failure patterns and toxicity were analyzed using the χ 2 test.

RESULTS

A total of 170 patients treated with HypoTRT (n = 69) or ConvTRT (n = 101) were eligible for analysis. The median PFS and OS were 13.7 and 25.3 months, respectively, in the ConvTRT cohort, which was similar to the HypoTRT cohort (PFS 18.2 months, p = 0.991, and OS 27.2 months, p = 0.698), with a median follow-up of 30 months. Multivariate analysis revealed that PCI and TNM stage were prognostic factors for PFS and that PCI was prognostic for OS. The patterns of failure (stratified by local-regional recurrence, distant metastasis or both as first relapse) were similar between the dose cohorts (p = 0.693, p = 0.330, p = 0.572). Distant metastasis remained the main failure pattern. The brain was the most frequent remote failure site, followed by bone, liver and adrenal gland. PCI improved the 2-year survival rate from 46.1% to 70.0% and the 2-year PFS rate from 20.9% to 45.3%, respectively (p < 0.001). Grade ≥3 esophagitis and pneumonitis occurred in 9.9% and 11.9%, respectively, of the patients in the ConvTRT cohort and in 11.6% and 10.0%, respectively, of those in the HypoTRT cohort (p = 0.815).

CONCLUSION

This retrospective analysis demonstrated that HypoTRT or ConvTRT combined with etoposide/platinum chemotherapy yielded statistically similar survival, treatment failure outcomes, and toxicity profiles. PCI correlated with improved PFS and OS.

Escalated hyperfractionated accelerated radiation therapy for locally advanced non-small cell lung cancer: a clinical phase II trial

BACKGROUND AND PURPOSE

To evaluate the feasibility, toxicity and the efficacy for locally advanced non-small cell lung cancer (NSCLC) treated with escalated hyperfractionated accelerated radiation therapy (EHART) combined with chemotherapy.

PATIENTS AND METHODS

The EHART consisted of irradiation delivered twice per day with >6-h interval and five treatment days per week. In the first and second weeks, 1.2 Gy/fraction b.i.d, was given, and then 1. /fraction b.i.d in the third week; 1.4 Gy/fraction b.i.d in the fourth week; and 1. /fraction b.i.d in the fifth week, respectively. The total tumor dose delivered was 66 Gy/50 fractions/5 weeks. All patients received neoadjuvant and adjuvant chemotherapy. The chemotherapeutic regimen used was either MVP (mitomycin C, vindesine, cis-platinum), or EP (etoposide and cis-platinum).

RESULTS

From February 1997 to February 1999, 73 eligible patients were registered. All were in stage IIIb with median age of 60 years (33-70). Of the 73 patients, 12 cases were withdrawn from the study due to Grade (Gr) III acute complications, distant metastases, or intercurrent diseases. Sixty-one patients completed the combined treatment as planned. A median of 4 cycles of chemotherapy (1-7) was administered and 66 Gy/50 fractions/36 days was delivered finally. The most common acute complication was radiation esophagitis, which occurred in 56 cases (77%), with Gr III in 11 cases (15%). Twenty-nine patients (40%) had acute pulmonary toxicity; with Gr III in 6 cases (8%). The median survival time was 13 months for the entire group. The 1-year and 2-year survival rates were 51 and 10%, respectively. Of the 61 patients who finished EHART, 34 were found to have locoregional progression. Thirty-two patients failed inside radiation fields, and 2 patients, outside radiation fields. The 1-year and 2-year locoregional progression-free rates were 71 and 34%, respectively. The 1-year and 2-year distant metastasis rates were 57 and 84%, respectively.

CONCLUSIONS

EHART combined with chemotherapy could be tolerated by most of the stage IIIb NSCLC patients with acceptable complications. Locoregional control was improved, but the long survival was not prolonged significantly predominantly due to distant metastases.

Prognostic predictors and long-term outcome of postoperative irradiation in thymoma: a study of 241 patients

The purpose of this study was to identify the prognostic predictors treated with postoperative irradiation in patients with thymoma. Two hundred forty-one patients with histologically confirmed thymoma were collected and retrospectively reviewed in this study. Fifty-four patients had stage I disease; 57, stage II; 120, stage III; 10, stage IV. One hundred sixty patients underwent total thymectomy; 63, partial resection; 18, debulking or biopsy. Patients were irradiated after surgery with median dose of 50 Gy by conventional fractionation. The overall survival rates at 5 and 10 years were 83.1% and 72.6%, respectively. The 10-year overall survival was 87% for stage I, 78.7% for stage II, 57.4% for stage III, and 24.3% for stage IV. The conclusions were drawn from this analysis. For stage I, the role of postoperative irradiation needed further investigation. For stage II-III, surgery and postoperative irradiation should be part of standard care. The favorable prognostic predictors were female, early stage, and surgical extirpation.

Intensity Modulated Radiation Therapy Plus Etoposide/Cisplatin for Patients With Limited Advanced Unresectable Thymic Epithelial Tumors: A Prospective Phase 2 Study

PURPOSE

This prospective phase 2 study evaluated the efficacy and safety of intensity modulated radiation therapy plus etoposide/cisplatin (EP) for patients with unresectable thymic epithelial tumors (TETs).

METHODS AND MATERIALS

Patients with limited advanced unresectable TETs whose lesions could be encompassed within radiation fields were enrolled in this study. Two cycles of EP (75 mg/m2 etoposide and 25 mg/m2 cisplatin on days 1-3 and days 29-31) were administered concurrently with radiation therapy, followed by 2 cycles after radiation therapy. The primary endpoint was the objective response rate. The secondary endpoints were the progression-free survival rate, overall survival rate, and incidence of adverse events.

RESULTS

Fifty-six patients were enrolled between June 2011 and May 2018. Twenty-two and 34 patients had thymomas and thymic carcinomas, respectively. The median age was 52 (range, 21-76) years, and 30 patients (53.6%) were men. Eight patients (14.3%) had stage III tumors, 6 (10.7%) had stage IVA tumors, and 42 (75.0%) had stage IVB tumors. The objective response rate was 85.7% (95% confidence interval, 76.3%-95.2%). With a median follow-up of 46 (range, 7-101) months, the 1-, 2-, and 5-year progression-free survival rates were 66.1%, 48.0%, and 29.5%, and the 1-, 2-, and 5-year overall survival rates were 91.0%, 76.2%, and 56.2%, respectively. The most common grade 3 to 4 adverse event was leukopenia (42.9%). Pulmonary fibrosis was also observed (5.3%).

CONCLUSIONS

Because intensity modulated radiation therapy with EP is effective and safe for limited advanced unresectable TETs, it could be a suitable treatment option for such patients.

Cisplatin/etoposide chemotherapy combined with twice daily thoracic radiotherapy for limited small-cell lung cancer: a clinical phase II trial

PURPOSE

To fit the situation of developing countries, where supportive care is not sufficient, a modified combined therapy of cisplatin/etoposide (EP) and hyperfractionated accelerated radiation therapy (HART) was conducted as a Phase II trial for limited-stage small-cell lung cancer (LSCLC) to evaluate the feasibility, toxicity, and tolerance of the combined therapy and to observe its efficacy and patterns of failure.

METHODS AND MATERIALS

Chemotherapy and radiation were sequentially administered in 1 to 3 cycles before and 3 to 5 cycles after HART. Chemotherapy contained cisplatin in doses of 25 to 30 mg/m(2) from Day 1 to Day 3 and etoposide in doses of 50 to 70 mg/m(2) from Day 1 to Day 3. The HART schedule consisted of radiation delivered in 1.4-Gy fractions, twice a day, at intervals longer than 6 h for 5 treatment days a week, to a total dose of 56 Gy in 40 fractions over 4 weeks.

RESULTS

From June 1997 to December 2000, 57 eligible patients were registered for this trial. All were limited stage, and the median age was 60 years (range, 25 to 70 years). Of the 57 patients, 3 were withdrawn because of distant metastases (1 case), Grade (Gr) III thrombocytopenia (1 case), and financial problems (1 case). Fifty-four patients completed the planned combined treatment. A median of 6 cycles of chemotherapy (range, 5-8 cycles) was administered during a median interval of 4.9 weeks (range, 3.0-8.9 weeks), and a radiation dose of 56 Gy in 40 fractions was delivered over 29 days. The most common acute complication was radiation esophagitis, which occurred in 41 cases (72%), 4 with Gr III. Thirty-six patients (64%) had acute pulmonary toxicity, 2 with Gr III. The median survival time was 24 months (95% CI, 21-28 months). The 1-year, 2-year, and 3-year survival rates were 81% (95% CI, 70%-91%), 49% (95% CI, 36%-62%), and 21% (95% CI, 10%-32%), respectively. Of 57 patients, 13 had locoregional progression. Nine patients failed inside radiation fields and 4 patients failed outside. The 1-year, 2-year, and 3-year locoregional progression-free survival rates were 85% (95% CI, 75%-95%), 74% (95% CI, 61%-87%), and 68% (95% CI, 52%-84%), respectively. Forty-four patients suffered distant metastases, 66% of which were in brain. The 1-year, 2-year, and 3-year distant metastasis rates were 31% (95% CI, 19%-43%), 59% (95% CI, 46%-72%), and 79% (95% CI, 68%-91%), respectively.

CONCLUSIONS

The study led to the following conclusions: (1) LSCLC patients tolerate HART at 56 Gy in 40 fractions over 4 weeks combined with 6 cycles of EP chemotherapy. (2) Both control of the tumor in the thorax and survival appear superior to conventional fractionated radiation but not as good as that in a study by Turrisi and colleagues. (3) This modified chemoradiation schedule could be recommended to LSCLC patients in developing countries. (4) The lessons learned from our study are (a) higher radiation doses may be needed for better locoregional control, and (b) prophylactic cranial irradiation is necessary for LSCLC patients who show complete response.

Simultaneously avoiding the hippocampus and hypothalamic-pituitary axis during whole brain radiotherapy: A planning study

Whole brain radiotherapy (WBRT) is the preferred treatment for multiple brain metastases, and patients with limited-stage small cell lung cancer undergo prophylactic cranial irradiation after complete remission. However, neurotoxicity remains a complication. In addition to protecting the hippocampus from irradiation to preserve cognitive function, it is also critical to avoid irradiating the hypothalamic-pituitary axis to preserve endocrine and immune function. This study aimed to evaluate the feasibility of delivering WBRT while protecting the hippocampus and hypothalamic-pituitary axis. Thirteen patients with limited-stage small cell lung cancer were enrolled in this study. The hippocampus, hypothalamus, and pituitary gland were contoured based on T1-weighted magnetic resonance imaging. The prescribed dose to the whole brain planning target volume was 25 Gy in 10 fractions. Two treatment plans using equispaced coplanar intensity-modulated radiotherapy (IMRT) were generated: WBRT with hippocampus avoidance (H-A) and WBRT with hippocampus, hypothalamus, and pituitary gland avoidance (H-HP-A). Both "H-A" and "H-HP-A" plans successfully protected the hippocampus, which received mean doses of 9.1 and 9.6 Gy, respectively (p = 0.0002), whereas the "H-HP-A" plan decreased the doses to both the hypothalamus (mean dose 11.06 Gy) and the pituitary gland (mean dose 10.66 Gy). Both "H-A" and "H-HP-A" plans showed similar target coverage of 95.1%. The homogeneity index of the "H-A" plan was slightly better than that of the "H-HP-A" plan (0.20 vs 0.23, p= 0.0012). In conclusion, the use of equispaced coplanar IMRT was found to simultaneously protect the hippocampus and hypothalamic-pituitary axis while delivering WBRT with acceptable target coverage and homogeneity.

Electroacupuncture prevents cognitive impairments by regulating the early changes after brain irradiation in rats

Cognitive impairments severely affect the quality of life of patients who undergo brain irradiation, and there are no effective preventive strategies. In this study, we examined the therapeutic potential of electroacupuncture (EA) administered immediately after brain irradiation in rats. We detected changes in cognitive function, neurogenesis, and synaptic density at different time points after irradiation, but found that EA could protect the blood-brain barrier (BBB), inhibit neuroinflammatory cytokine expression, upregulate angiogenic cytokine expression, and modulate the levels of neurotransmitter receptors and neuropeptides in the early phase. Moreover, EA protected spatial memory and recognition in the delayed phase. At the cellular/molecular level, the preventative effect of EA on cognitive dysfunction was not dependent on hippocampal neurogenesis; rather, it was related to synaptophysin expression. Our results suggest that EA applied immediately after brain irradiation can prevent cognitive impairments by protecting against the early changes induced by irradiation and may be a novel approach for preventing or ameliorating cognitive impairments in patients with brain tumors who require radiotherapy.

Proton and Carbon Ion Radiation Therapy Decreased Severe Lymphopenia by Reducing Thoracic Vertebra and Aortic Doses in Non-Small Cell Lung Cancer Versus Intensity Modulated Radiation Therapy

PURPOSE

Lymphopenia is a common adverse effect of radiation therapy (RT). Little is known about the difference in lymphopenia between intensity modulated (photon) radiation therapy (IMRT) and proton and carbon ion radiation therapy (PCIRT). This study aimed to investigate lymphopenia differences between IMRT and PCIRT in non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

Clinical and dosimetric parameters were collected from 343 patients who received definitive IMRT or PCIRT for NSCLC. Severe lymphopenia (SRL) was defined as an absolute lymphocyte count (ALC) ≤0.5 × 103 cells/μL. Overall survival (OS) was analyzed using the Kaplan-Meier method. Propensity score matching was performed between the IMRT and PCIRT groups. Least absolute shrinkage and selection operator analysis was used to select appropriate dosimetric parameters. Univariate and multivariate logistic regression analyses were conducted to identify the predictors of SRL.

RESULTS

Compared with the IMRT group, the PCIRT group was less likely to develop SRL (P < .001). Compared with the non-SRL group, the SRL group showed significant association with poorer OS, with a median survival time of 29.2 versus 15.0 months (P = .046). IMRT was an independent risk factor of SRL (P = .004). A lower ALC before RT (P = .030) and larger planning target volume (PTV) (P = .002) were also significant independent risk factors for SRL. Moreover, the majority of dosimetric parameters of organs at risk in PCIRT were lower than those in IMRT (P < .001). Thoracic vertebra V5 (P = .002) and aorta V5 (P = .026) were identified as independent risk predictors of SRL after adding dosimetric parameters to the regression model.

CONCLUSIONS

Compared with IMRT, PCIRT could reduce SRL incidence, possibly by limiting thoracic vertebra and aortic doses, and SRL was associated with poor outcomes in patients with NSCLC.

Three-dimensional conformal radiation therapy alone for esophageal squamous cell carcinoma: 10-year survival outcomes

BACKGROUND

Concurrent chemoradiation is the standard treatment for locally advanced esophageal squamous cell carcinoma (SCC). We conducted a phase II study to explore the effect of three-dimensional conformal radiotherapy (3-DCRT) alone for patients with locally advanced esophageal SCC. This study aimed to analyze the long-term survival outcomes.

METHODS

Between November 2004 and April 2007, 30 patients with thoracic esophageal SCC underwent late-course sequential boost 3-DCRT at Fudan University Shanghai Cancer Center. The planning target volume (PTV1) comprised a 1.2-1.5 cm lateral margin around the gross tumor volume and a 3.0 cm margin, superior and inferior to the gross tumor volume. PTV2 encompassed the gross tumor volume with a margin of 0.5-0.7 cm. The PTV1 dose delivered was 50 Gy, and the PTV2 dose was a boost dose of 16 Gy, resulting in a total dose of 66 Gy. No chemotherapy was administered.

RESULTS

The median follow-up time was 30 months for all patients, and 132 months for patients who were alive. The median overall survival was 27 months (95% confidence interval [CI] 18.9-35.0). The 2-, 5-, and 10-year overall survival rates were 56.6%, 33.3%, and 26.6%, respectively. The median progression-free survival was 14 months (95% CI 7.7-20.2 months), and the 2-, 5-, and 10-year progression-free survival rates were 33.3%, 30.0%, and 26.6%, respectively. No severe late toxicity was observed in long-term survivors.

CONCLUSION

Late-course sequential boost 3-DCRT is safe and feasible with promising long-term outcomes for esophageal SCC.

Variation in background intensity affects PET-based gross tumor volume delineation in non-small-cell lung cancer: the need for individualized information

PURPOSE

Efficient tumor volume delineation by the combined use of PET/CT scanning is necessary for the proper treatment of non-small cell lung cancer (NSCLC). To understand the effect of variation in background intensity on PET-based gross tumor volume (GTV) delineation, we determined the background standard uptake values (SUVs) in normal lung, aorta (blood pool), and liver tissues and determined GTVs using different methods.

METHODS

Thirty-seven previously untreated patients with pathologically confirmed NSCLC underwent PET/CT scanning with (18)F-fluorodeoxyglucose ((18)F-FDG). To obtain (18)F-FDG uptake values in normal tissues, regions of interest in the lung lobes (left upper, left lower, right upper, right middle, and right lower), aorta, and liver zones (left, intermediate, and right) were measured. The coefficient of variation (CV) of the SUV was measured for each normal structure. The CT-based GTV (GTV(CT)) was considered as the standard to which all PET-based GTVs were compared, and the correlation coefficient was analyzed to compare GTV obtained by the various delineation methods. Linear and logarithmic regression analyses were used to determine the relationship between GTV(CT) and GTV(PET).

RESULTS

Normal lung tissue showed a significantly lower SUV and less stability than tissue of the aorta or liver. For the lung, aorta, and liver, the maximum SUV (SUV(max)) was 0.82 ± 0.32, 2.35 ± 0.37, and 3.24 ± 0.50 (CV: 38.79%, 15.82%, and 15.30%) and average SUV (SUV(ave)) was 0.49 ± 0.18, 1.68 ± 0.32, and 2.34 ± 0.36 (CV: 36.38%, 18.92%, and 15.44%), respectively. The SUVs of the lung varied from lobe to lobe. The GTV delineation method using the SUV(ave) of the lung lobe in which the tumor was found as background in the source-to-background ratio (SBR) method showed the best correlation with the volume of CT-based GTV (r=0.81).

CONCLUSIONS

Our results show vast variation in the SUV among normal tissues, as well as in the different lung lobes. The tumor volume delineated using the SBR method correlated well with the CT-based tumor volume. We conclude that it is reasonable and precise to contour GTV in patients with NSCLC after taking into account the background intensity of the lung lobe in which the tumor is found.