Prospective study on late renal toxicity following postoperative chemoradiotherapy in gastric cancer

Comparative dosimetric study of spot-scanning proton therapy versus volumetric-modulated radiation therapy for extrahepatic bile duct cancer

This study aimed to compare the dose distributions and clarify the dosimetric characteristics of spot-scanning proton therapy (SSPT) and photon volumetric modulated arc therapy (VMAT) for extrahepatic bile duct cancer (EBDC). This retrospective study included 10 patients with EBDC treated with real-time image-gated SSPT. Using the simultaneous integrated boost technique, the 2 prescription dose levels for planning target volumes were 72.6 and 44 Gy, delivered in 22 fractions. Plan quality comparisons were conducted by analyzing various parameters, including homogeneity, conformity, dose to organs at risk, and normal tissue complication probability (NTCP) for radiation-induced liver damage (RILD). The target dose distributions using SSPT were almost equivalent to those achieved using photon VMAT. There was a significant reduction in all liver dose parameters, the NTCP value for RILD, and kidney dose (mean, V12 Gy, and V18 Gy) in SSPT than in photon VMAT. No significant differences were observed in the intestinal doses in the high-dose area. Thus, compared with photon VMAT, SSPT for EBDC significantly reduced radiation doses to the liver and kidneys and has shown potential clinical benefits of reduced radiation-induced toxicity.

Prediction of chronic kidney disease in abdominal cancers radiation therapy using the functional assays of normal tissue complication probability models

Aim

The purpose of this study is to predict chronic kidney disease (CKD) in the radiotherapy of abdominal cancers by evaluating clinical and functional assays of normal tissue complication probability (NTCP) models.

Materials and Methods

Radiation renal damage was analyzed in 50 patients with abdominal cancers 12 months after radiotherapy through a clinical estimated glomerular filtration rate (eGFR). According to the common terminology criteria for the scoring system of adverse events, Grade 2 CKD (eGFR ≤30-59 ml/min/1.73 m²) was considered as the radiation therapy endpoint. Modeling and parameter estimation of NTCP models were performed for the Lyman-equivalent uniform dose (EUD), the logit-EUD critical volume (CV), the relative seriality, and the mean dose model.

Results

The confidence interval of the fitted parameters was 95%. The parameter value of D₅₀ was obtained 22-38 Gy, and the n and s parameters were equivalent to 0.006 -3 and 1, respectively. According to the Akaike's information criterion, the mean dose model predicts radiation-induced CKD more accurately than the other models.

Conclusion

Although the renal medulla consists of many nephrons arranged in parallel, each nephron has a seriality architecture as renal functional subunits. Therefore, based on this principle and modeling results in this study, the whole kidney organs may have a serial-parallel combination or a secret architecture.

Analysis of Chronic Kidney Disease After Radiation Therapy for Gastric/Duodenal Mucosa-Associated Lymphoid Tissue Lymphoma

Purpose

This study aimed to evaluate the relationship between chronic kidney disease (CKD) after radiation therapy for gastric/duodenal mucosa-associated lymphoid tissue lymphoma and dose-volume histogram of the kidneys.

Methods and Materials

We retrospectively reviewed 40 patients who received 3-dimensional conformal radiation therapy. CKD was evaluated using the Common Terminology Criteria for Adverse Events version 5.0. The mean dose of bilateral kidneys/right kidney/left kidney (D_{mean of b-kidneys}) (D_{mean of r-kidney}) (D_{mean of l-kidney}), bilateral kidneys/right kidney/left kidney volume receiving ≥ x Gy (V_{x of b-kidneys}) (V_{x of r-kidney}) (V_{x of l-kidney}), and patients’ baseline clinical characteristics were analyzed.

Results

The median radiation therapy dose was 28 (range, 24-44.8) Gy in 14 fractions. The median follow-up period was 63.1 months, and the 5-year cumulative incidence of grade 2 CKD rate was 14.8%. Among several factors, V_{5 of b-kidneys} was most strongly associated with grade 2 or worse CKD, with an area under the curve of 0.81 in the receiver operating characteristic curve. The 5-year incidence rate in patients with V_{5 of b-kidneys} ≥ 58% was significantly higher than that in other patients (24.5% and 9.8%, respectively; P < .05).

Conclusions

In this study using 3-dimensional conformal radiation therapy, the rate of adverse events at 5 years was low, many patients showed toxicity after 5 years; thus, continuous follow-up is necessary to detect potential nephrotoxicity. Our data demonstrate that V_{5 of b-kidneys} was most strongly associated with the risk of CKD. With lower doses and more advanced techniques in recent years, the incidence of CKD may be further reduced.

Customization of a Model For Knowledge-Based Planning to Achieve Ideal Dose Distributions in Volume Modulated arc Therapy for Pancreatic Cancers

Purpose:

To evaluate customizing a knowledge-based planning (KBP) model using dosimetric analysis for volumetric modulated arc therapy for pancreatic cancer.

Materials and Methods:

The first model (M1) using 56 plans and the second model (M2) using 31 plans were created in the first 7 months of the study. The ratios of volume of both kidneys overlapping the expanded planning target volume to the total volume of both kidneys (V_overlap/V_whole) were calculated in all cases to customize M1. Regression lines were derived from V_overlap/V_whole and mean dose to both kidneys. The third model (M3) was created using 30 plans which data put them below the regression line. For validation, KBP was performed with the three models on 21 patients.

Results:

V₁₈ of the left kidney for M1 plans was 7.3% greater than for clinical plans. Dmean of the left kidney for M2 plans was 2.2% greater than for clinical plans. There was no significant difference between all kidney doses in M3 and clinical plans. Dmean of the left kidney for M2 plans was 2.2% greater than for clinical plans. Dmean to both kidneys did not differ significantly between the three models in validation plans with V_overlap/V_whole lower than average. In plans with larger than average volumes, the Dmean of validation plans created by M3 was significantly lower for both kidneys by 1.7 and 0.9 Gy than with M1 and M2, respectively.

Conclusions:

Selecting plans to register in a model by analyzing dosimetry and geometry is an effective means of improving the KBP model.

H. pylori negative gastric MALT lymphoma with API2-MALT1 translocation treated by endoscopic submucosal dissection: A case report

RATIONALE

API2-MALT1 positive gastric mucosa-associated lymphoid tissue (MALT) lymphomas are considered to have favorable prognosis. We report a case of API2-MALT1 positive gastric MALT lymphoma, treated by endoscopic submucosal dissection (ESD).

PATIENT CONCERNS

A 51-year-old man underwent esophagogastroduodenoscopy (EGD) for the annual health checkup examination.

DIAGNOSES

The EGD showed a reddish depressed lesion with small reddish spots in the lower gastric body. There was no endoscopic atrophy in the entire stomach and Helicobacter pylori (H. pylori) serum test was negative. Infiltration of small lymphocytes was shown in the gastric tissues obtained by the endoscopic biopsy. The fluorescence in situ hybridization using the biopsy samples confirmed the presence of genetic translocation of API2-MALT1, suggesting that the lesion is API2-MALT1 positive MALT lymphoma.

INTERVENTIONS

Since endoscopic ultrasound suggested that the lesion was localized within the lamina propria mucosae, we performed ESD to achieve the en bloc resection of the lesion.

OUTCOMES

Conclusive diagnosis of gastric MALT lymphoma was made based on the resected specimen. Lateral and vertical margins were negative. No lymphoma cells were detected using endoscopic biopsy after 5 years.

LESSONS

Our report suggests that ESD can be considered as alternative treatment for API2-MALT1 positive gastric MALT lymphoma if the lesion was localized within the gastric mucosa.

Kidney Function after Treatment for Childhood Cancer: A Report from the St. Jude Lifetime Cohort Study

BACKGROUND

Survivors of childhood cancer may be at increased risk for treatment-related kidney dysfunction. Although associations with acute kidney toxicity are well described, evidence informing late kidney sequelae is less robust.

METHODS

To define the prevalence of and risk factors for impaired kidney function among adult survivors of childhood cancer who had been diagnosed ≥10 years earlier, we evaluated kidney function (eGFR and proteinuria). We abstracted information from medical records about exposure to chemotherapeutic agents, surgery, and radiation treatment and evaluated the latter as the percentage of the total kidney volume treated with ≥5 Gy (V5), ≥10 Gy (V10), ≥15 Gy (V15), and ≥20 Gy (V20). We also used multivariable logistic regression models to assess demographic and clinical factors associated with impaired kidney function and Elastic Net to perform model selection for outcomes of kidney function.

RESULTS

Of the 2753 survivors, 51.3% were men, and 82.5% were non-Hispanic White. Median age at diagnosis was 7.3 years (interquartile range [IQR], 3.3-13.2), and mean age was 31.4 years (IQR, 25.8-37.8) at evaluation. Time from diagnosis was 23.2 years (IQR, 17.6-29.7). Approximately 2.1% had stages 3-5 CKD. Older age at evaluation; grade ≥2 hypertension; increasing cumulative dose of ifosfamide, cisplatin, or carboplatin; treatment ever with a calcineurin inhibitor; and volume of kidney irradiated to ≥5 or ≥10 Gy increased the odds for stages 3-5 CKD. Nephrectomy was significantly associated with stages 3-5 CKD in models for V15 or V20.

CONCLUSIONS

We found that 2.1% of our cohort of childhood cancer survivors had stages 3-5 CKD. These data may inform screening guidelines and new protocol development.

Optimal Timing to Surgery After Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer

BACKGROUND

The relationship between time to surgery (TTS) and survival benefit is not sufficiently demonstrated by previous studies in locally advanced gastric cancer (LAGC). This study aims to assess the impact of TTS after neoadjuvant chemotherapy (NACT) on long-term and short-term outcomes in LAGC patients.

METHODS

Data were collected from patients with LAGC who underwent NACT between January 2007 and January 2018 at our institution. Outcomes assessed were long-term survival, pathologic complete response (pCR) rate, and postoperative complications.

RESULTS

This cohort of 426 patients was divided into five groups by weeks of TTS. Under cox regression, compared to other groups, the 22-28 days and 29-35 days groups revealed a better OS (≤21 vs. 22-28 days: HR 1.54, 95% CI = 0.81-2.93, P = 0.185; 36-42 vs. 22-28 days: HR 2.20, 95% CI = 1.28-3.79, P = 0.004; 43-84 vs. 22-28 days: HR 1.83, 95% CI = 1.09-3.06, P = 0.022) and PFS (≤21 vs. 22-28 days: HR 1.54, 95% CI = 0.81-2.93, P = 0.256; 36-42 vs. 22-28 days: HR 2.20, 95% CI = 1.28-3.79, P = 0.111; 43-84 vs. 22-28 days: HR 1.83, 95% CI = 1.09-3.06, P = 0.047). Further analysis revealed a better prognosis in patients with TTS within 22-35 days (OS: HR 1.78 95% CI = 1.25-2.54, P = 0.001; PFS: HR 1.49, 95% CI = 1.07-2.08, P = 0.017). Postoperative stay was significantly higher in the ≤21 days group, while other parameters revealed no statistical significance (P > 0.05). Restricted cubic spline depicted the nonlinear relationship between TTS and OS/PFS.

CONCLUSION

Patients who received surgery within 3-5 weeks experienced the maximal survival benefit without an increase in postoperative complications or lowering the rate of pCR. Further investigations are warranted.

Dosimetric impact of baseline drift in volumetric modulated arc therapy with breath holding

BACKGROUND

We investigated the change of dose distributions in volumetric modulated arc therapy (VMAT) under baseline drift (BD) during breath holding.

MATERIALS AND METHODS

Ten VMAT plans recalculated to a static field at a gantry angle of 0° were prepared for measurement with a 2D array device and five original VMAT plans were prepared for measurement with gafchromic films. These measurement approaches were driven by a waveform reproducing breath holding with BD. We considered breath holding times of 15 and 10 s, and BD at four speeds; specifically, BD0 (0 mm/s), BD0.2 (0.2 mm/s), BD0.3 (0.3 mm/s), and BD0.4 (0.4 mm/s). The BD was periodically reproduced from the isocenter along the craniocaudal direction and the shift during breath holding (ShiftBH) ranged 0-6 mm.The dose distribution of BD0.2, BD0.3 and BD0.4 were compared to that of BD0 using gamma analysis with the criterion of 2%/2 mm.

RESULTS

The mean pass rates of each ShiftBH were 99.8% and 98.9% at 0 mm, 96.8% and 99.4% at 2 mm, 94.9% and 98.6% at 3 mm, 91.5% and 98.4% at 4 mm, 70.8% and 94.1% at 4.5 mm, and 55.0% and 83.6% at 6 mm for the array and film measurements, respectively.

CONCLUSION

We found significant differences in ShiftBH above 4 mm (ρ < 0.05). Hence, it is recommended that breath holding time should be shortened for patients to preserve the reproducibility of dose distributions.

miR‑204‑5p promotes apoptosis and inhibits migration of gastric cancer cells by targeting HER‑2

Gastric cancer is one of the most common types of cancer worldwide, with a high incidence and mortality rate. MicroRNAs (miRs) play an important role in tumorigenesis, cell proliferation, migration, apoptosis and metastasis of cancer. The present study aimed to investigate the role and potential mechanism of miR‑204‑5p in gastric cancer. The mRNA expression levels of miR‑204‑5p in gastric cancer were determined by reverse transcription‑quantitative PCR. Cell proliferation was determined using Cell Counting Kit‑8 and colony formation assays. Flow cytometry analysis was performed to detect the cell apoptosis rate. Wound healing and Transwell assays were carried out to determine the cell migration and invasion rates, respectively. A putative binding site of miR‑204‑5p in the 3' untranslated region of human epidermal growth factor receptor 2 (HER‑2) was predicted using a bioinformatics algorithm and confirmed using a dual‑luciferase reporter assay. miR‑204‑5p levels were downregulated in gastric cancer cells. Overexpression of miR‑204‑5p significantly inhibited cell proliferation and decreased cell colony formation. Additionally, miR‑204‑5p decreased the migration and invasion rates of gastric cancer cells. Furthermore, an increased apoptotic rate was detected following overexpression of miR‑204‑5p, along with increased expression levels of Bax and decreased expression levels of Bcl‑2. HER‑2 was a direct target of miR‑204‑5p, and inhibition of HER‑2 acted as a tumor suppressor by inhibiting cell proliferation, migration and invasion, and promoting cell apoptosis, which was reversed by the inhibition of miR‑204‑5p expression. These results suggested that miR‑204‑5p could exert its anti‑tumor function by inhibiting cell proliferation, migration and invasion, and promoting cell apoptosis via regulation of HER‑2, which may be a potential therapeutic target for gastric cancer.

Adjuvant chemoradiation for gastric carcinoma: State of the art and perspectives

An estimated 990,000 new cases of gastric cancer are diagnosed worldwide each year. Surgical excision, the only chance for prolonged survival, is feasible in about 20% of cases. Even after surgery, the median survival is limited to 12 to 20 months due to the frequency of locoregional and/or metastatic recurrences. This led to clinical trials associating surgery with neoadjuvant or adjuvant treatments to improve tumor control and patient survival. The most studied modalities are perioperative chemotherapy and adjuvant chemoradiotherapy. To date, evidence has shown a survival benefit for postoperative chemoradiotherapy and for perioperative chemotherapy. Phase III trials are ongoing to compare these two modalities. The aim of this review is to synthesize current knowledge about adjuvant chemoradiotherapy in the management of gastric adenocarcinoma, and to consider its prospects by integrating modern radiotherapy techniques.

Using Intensity-Modulated Radiotherapy to Spare the Kidney in a Patient with Seminoma and a Solitary Kidney: A Case Report

Aims and background

Radiotherapy-related kidney injury is multifactorial and influenced by radiation dose-volume distributions, patient-related factors, and chemotherapy. Traditional radiation parameters for the kidney are based on pre-intensity-modulated radiotherapy (IMRT) data and focus on limiting the volume receiving high dose. We report a case of testicular seminoma with paraaortic adenopathy in a patient with a solitary kidney treated with radiotherapy.

Methods

A comparison was performed for IMRT and two 3D-conformal techniques. In our case, IMRT reduced the volume of kidney receiving high dose but increased the volume receiving low dose.

Results

Given the lack of data for suggesting that large renal volumes treated to low doses would cause excess toxicity, the consensus opinion was to proceed with IMRT. The patient tolerated treatment well without evidence of radiotherapy-related kidney injury.

Conclusions

As patients are treated with increasingly complex techniques such as IMRT, understanding low dose effects and monitoring low dose parameters may become clinically important.

Volumetric-modulated arc therapy versus intensity-modulated radiotherapy for large volume retroperitoneal sarcomas: A comparative analysis of dosimetric and treatment delivery parameters

Purpose

To compare dosimetric and treatment delivery parameter differences between volumetric‐modulated arc radiotherapy (VMAT) and intensity‐modulated radiotherapy (IMRT) for large volume retroperitoneal sarcomas (RPS).

Materials and Methods

Both VMAT and IMRT planning were performed on CT datasets of 10 patients with RPS who had been previously treated with preoperative radiotherapy. Plans were optimized to deliver ≥95% dose to the PTV and were evaluated for conformity and homogeneity. Dose to the organs at risk (OARs) (kidney, liver, spinal cord, and bowel space), unspecified tissue, and dose evaluation volumes (DEVs) at 1, 2, and 5 cm from PTV were calculated and compared. Monitor units (MUs) and treatment delivery times were recorded and compared between the two techniques. The deliverability of the large volume RPS VMAT plans was verified by portal dosimetry on a Truebeam™ linac.

Results

VMAT and IMRT plans were equivalent for PTV coverage and homogeneity (P > 0.05); however, VMAT plans had slightly better conformity index, CI (P < 0.001). Doses to the OARs were not significantly different between VMAT and IMRT plans (P > 0.05). Mean doses to the unspecified tissue as well as at 1, 2, and 5 cm DEVs were lower with VMAT compared with IMRT, P = 0.04 and P < 0.01, respectively. MUs and average beam‐on times were both significantly lower in the VMAT vs IMRT plans, P < 0.001 and P = 0.001, respectively. All VMAT plans passed portal dosimetry delivery verification with an average gamma passing rate of 99.6 ± 0.4%.

Conclusions

VMAT planning for large volume RPS improved CI, and achieved comparable OAR sparing, as compared with IMRT. As treatment delivery time was lower, the use of VMAT for RPS may translate into improved treatment delivery efficiency.

Dosimetric comparison of 3-dimensional conformal radiotherapy, volumetric modulated arc therapy, and helical tomotherapy for postoperative gastric cancer patients

PURPOSE

To compare dosimetric data for the planning target volume (PTV) and organs at risk (OARs) between 3-dimensional conformal radiotherapy (3DCRT), volumetric modulated arc therapy (VMAT), and helical tomotherapy [1].

MATERIALS AND METHODS

The dosimetric data for 15 gastric cancer patients treated with 3DCRT, VMAT, or HT techniques were used. Cumulative dosimetric parameters, homogeneity index (HI), and conformal index (CI) were compared for the PTV and OARs.

RESULTS

The average maximum doses of PTV were significantly higher in VMAT plans than in 3DCRT (p = 0.04) and HT (p = 0.02) plans, whereas minimum dose values were significantly lower in 3DCRT plans compared with VMAT (p < 0.001) and HT (p = 0.02) plans. Liver mean dose (D _mean) and D _mean values for both kidneys were significantly lower in HT plans than in 3DCRT and VMAT plans. The doses in high dose regions (V30-V45) using 3DCRT plans were significantly higher compared to both VMAT and HT plans. The bowel V5-V30 and V45 was significantly less in HT plans compared to VMAT plans. There were no significant differences in dose sparing of the spinal cord.

CONCLUSIONS

The HT plans reduced the maximum dose applied to the target and improved the conformality and homogeneity of radiation, while providing sufficient PTV coverage.

Comparison of changes in renal function with dosimetric parameters in gastric cancer patients treated with adjuvant chemoradiotherapy

PURPOSE

Our objective was to analyze kidney damage using glomerular filtration rate (GFR) and dynamic renal scintigraphy (DRS) compared with dose volume histogram (DVH) parameters in gastric cancer patients.

MATERIALS AND METHODS

Twenty-two gastric cancer patients treated with postoperative chemoradiotherapy were retrospectively evaluated. Student's t test was used to compare pre- and posttreatment GFR and creatinine values. The relative contribution of the left and right kidney in DRS results was expressed as left-to-right ratio (L/R), and the percentage of initial and control participation ratio difference was calculated. Spearman's correlation analysis was used to compare the percentage difference of L/R ratio with DVH parameters of each kidney.

RESULTS

In DRS analysis, decrease in left kidney cortical function was observed in one patient. V5-V10 of the left and bilateral kidneys were significantly associated with GFR decline. None of the DVH parameter was significantly associated with L/R ratio. However, the V15 and D_mean of the bilateral kidney were significantly correlated with greater decrease in L/R ratio in seven patients whose posttreatment DRS period was > 12 months.

CONCLUSIONS

Decline in renal function, even with current renal constraints, was observed. Minimization of V5, V10, and V15 and mean dose (D_mean) to the kidney should be considered.

Should functional renal scans be obtained prior to upper abdominal IMRT for pancreatic cancer?

BACKGROUND

Upper abdominal irradiation for pancreatic cancer is administered in close proximity to the radiation-sensitive kidneys. There is difficulty in defining dose-volume parameters to predict late renal toxicity after partial kidney irradiation. Less than 10% of the general population is estimated to have asymmetrical kidney function; however, there are no studies that examine this in patients with pancreatic cancer. The primary purpose of this study was to determine the prevalence of asymmetrical kidney function in patients with pancreatic cancer. A secondary aim was to determine if asymmetrical kidney function was associated with abnormal laboratory values or kidney size on computed tomography scans. Finally, we aimed to develop recommendations for when a functional renal scan in patients with pancreatic cancer should be ordered.

METHODS AND MATERIALS

We performed a retrospective review of patients with resectable, borderline resectable, and locally advanced pancreatic cancer who received abdominal radiation therapy and had preradiation functional renal scans between 2009 and 2015. Asymmetrical kidney function was defined as a difference between the 2 kidneys that was ≥60%/40% on a functional renal scan. Serum studies (blood urea nitrogen [BUN], creatinine [Cr], and glomerular filtration rate [GFR]) and abdominal computed tomography scans were routinely obtained before simulation.

RESULTS

Of the 204 patients examined, 23 (11.2%) had asymmetrical kidney function that was identified on preradiation functional renal scans. Elevated Cr or BUN, a GFR <60, or a medical history that suggested abnormal renal function were not significantly associated with asymmetrical kidney function. Only 6 of 23 patients (26%) with asymmetrical kidney function had a notable difference in kidney size.

CONCLUSIONS

In our series, approximately 11% of patients with pancreatic cancer have asymmetrical kidney function that was not identified by kidney size, serum BUN, Cr, GFR, or a significant medical history. These data suggest that in cases in which renal radiation doses exceed a V18 of 20% to 30% or there is concern about baseline renal function, a functional renal scan should be considered.

Patterns of Initial Recurrence in Gastric Adenocarcinoma in the Era of Preoperative Therapy

BACKGROUND

We sought to determine the sites of recurrence and identify predicting factors for recurrence and survival in patients who underwent gastrectomy for adenocarcinoma at an institution where preoperative therapy is commonly used for advanced gastric cancer.

METHODS

We collected clinicopathologic data and sites of recurrence from a prospectively maintained database of patients who underwent potentially curative resection of gastric or gastroesophageal adenocarcinoma at our institution in 1995-2014, and we assessed associations between these characteristics and recurrence patterns and survival.

RESULTS

We identified 488 patients who underwent R0 resection of localized gastric cancer. The median age was 63 years (interquartile range 53-71 years), and 60% were male. The most common T and N categories, per endoscopic ultrasonography, were T3 (58%) and N0 (61%). Preoperative treatment was used in 61% of patients. A total of 125 (26%) patients experienced recurrence during follow-up. Recurrences were locoregional in 19 patients (15%), peritoneal in 61 (49%), and nonperitoneal distant in 67 (54%). The peritoneum also was the most common organ of recurrence (49%), followed by the liver (21%). The median time from primary resection to recurrence was 2.7 years for locoregional, 1.3 years for peritoneal, and 0.6 years for nonperitoneal distant recurrence (p = 0.01). Median overall survival was markedly shorter after peritoneal and nonperitoneal distant recurrences than after locoregional recurrences.

CONCLUSIONS

The peritoneum was a common site of recurrence after curative resection of gastric cancer and was associated with poor survival. Prophylactic treatment targeting the peritoneal cavity might improve survival of advanced gastric cancer.

Dosimetric Comparison of Three Different Radiotherapy Techniques in Antrum-Located Stomach Cancer

Background:

The current optimal radiotherapy (RT) planning technique for stomach cancer is controversial. The design of RT for stomach cancer is difficult and differs according to tumor localization. Dosimetric and clinical studies have been performed in patients with different tumor localizations. This may be the main source of inconsistencies in study results. For this reason, we attempted to find the optimal RT technique for patients with stomach cancer in similar locations.

Methods:

This study was based on the computed tomography datasets of 20 patients with antrum-located stomach cancer. For each patient, treatments were designed using physical wedge-based conformal RT (WB-CRT), field-in-field intensity-modulated RT (FIF-IMRT), and dynamic intensity-modulated RT (IMRT). The techniques were compared in terms of expected target volume coverage and the dose to organs at risk (OAR) using a dose-volume histogram analysis.

Results:

FIF-IMRT was the most homogenous technique, with a better homogeneity index than WBCRT (p<0.001) or IMRT (p<0.001). However, IMRT had a better conformity index than WBCRT (p<0.001) or FIF-IMRT (p<0.001). Additionally, all OAR, including the kidneys, liver, and spinal cord, were better protected with IMRT than with WBCRT (p=0.023 to <0.001) or FIF-IMRT (p=0.028 to <0.001).

Conclusions:

In comparison to FIF-IMRT and WBCRT, IMRT appears to be the most appropriate technique for antrum-located stomach cancer. To establish whether IMRT is superior overall will require clinical studies, taking into account differences in both tumor localization (cardia, body, and antrum) and organ movement in patients with stomach cancer.

Long-term observations of radiation-induced creatinine clearance reduction and renal parenchymal volume atrophy

PURPOSE

The kidney is a dose-limiting organ for upper abdominal radiotherapy. In this study, radiation-induced kidney injury represented by changes of creatinine clearance (Ccr) and renal parenchymal volume measured by computed tomography (CT) were evaluated by analysing dose-volume histograms (DVHs) in patients with primary gastric diffuse large B-cell lymphoma (PGDLBCL) treated with chemoradiotherapy.

MATERIALS AND METHODS

Thirty-eight PGDLBCL patients (seventy-six kidneys) treated with chemoradiotherapy were included in this study. At least 4 years of follow-up was required for eligibility. Patients underwent (immuno-) chemotherapy followed by radiotherapy with approximately 40Gy to the whole stomach and perigastric lymph nodes. Ccr and CT were obtained at least annually. Changes of Ccr and renal parenchymal volume before and 4years after radiotherapy were compared using DVH parameters.

RESULTS

Mean Ccr decreased significantly from 82.7mL/min (range, 39-124mL/min) before radiotherapy to 70.4mL/min (range, 35-109mL/min) (p=0.01) 4years after radiotherapy. Mean reduction of bilateral renal parenchymal volume was 12% (range, -5-37%) in the same time period. Ccr and renal parenchymal volume tended to lower over time more than 4years after radiotherapy. Concerning DVH analysis, V20Gy⩾26.6% and D30%⩾19Gy had a significant risk of bilateral renal atrophy of ⩾14% and reduction of the Ccr⩾20mL/min.

CONCLUSION

This study revealed that there was a definite relationship between DVH, renal atrophy and Ccr reduction. V20Gy<26.6% and D30%<19Gy appeared to be safe dose constraints for a Ccr reduction of <20mL/min 4years after radiotherapy.

Dosimetric and clinical toxicity comparison of critical organ preservation with three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, and RapidArc for the treatment of locally advanced cancer of the pancreatic head

PURPOSE

We compared dosimetry and clinical toxicity for 3-dimensional conformal radiotherapy (3D-crt), intensity-modulated radiotherapy (imrt), and RapidArc (Varian Medical Systems, Palo Alto, CA, U.S.A.) in locally advanced pancreatic cancer (lapcc). We hypothesized that the technique with better sparing of organs at risk (oars) and better target dose distributions could lead to decreased clinical toxicity.

METHODS

The study analyzed 280 patients with lapcc who had undergone radiotherapy. The dosimetry comparison was performed using 20 of those patients. Dose-volume histograms for the target volume and the oars were compared. The clinical toxicity comparison used the 280 patients who received radiation with 3D-crt, imrt, or RapidArc.

RESULTS

Compared with 3D-crt, RapidArc and imrt both achieved a better conformal index, homogeneity index, V95%, and V110%. Compared with 3D-crt or imrt, RapidArc reduced the V10, V20, and mean dose to duodenum, the V20 of the right kidney, and the liver mean dose. Compared with 3D-crt, RapidArc reduced the V35, and V45 of duodenum, the mean dose to small bowel, and the V15 of right kidney. The incidences of grades 3 and 4 diarrhea (p = 0.037) and anorexia (p = 0.042) were lower with RapidArc than with 3D-crt, and the incidences of grades 3 and 4 diarrhea (p = 0.027) were lower with RapidArc than with imrt.

CONCLUSIONS

Compared with 3D-crt or imrt, RapidArc showed better sparing of oars, especially duodenum, small bowel, and right kidney. Also, fewer acute grades 3 and 4 gastrointestinal toxicities were seen with RapidArc than with 3D-crt or imrt. A technique with better sparing of oars and better target dose distributions could result in decreased clinical toxicities during radiation treatment for lapcc.

β-elemene enhances the radiosensitivity of gastric cancer cells by inhibiting Pak1 activation

AIM: To explore the potential of β-elemene as a radiosensitizer for gastric cancer cells and the underlying mechanisms.

METHODS: SGC7901, MKN45, MKN28, N87, and AGS human gastric cancer cell lines were used to screen for radioresistant gastric cancer cell lines. A 3-(4,5-dimeth-ylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay was used to determine the effects of β-elemene and IPA-3 on cell viability in MKN45 and SGC7901 gastric cancer cell lines. A clonogenic survival assay and annexin V-FITC/PI apoptosis detection assay were used to evaluate cellular radiosensitivity and radiation-induced cell death, respectively. A proteomic method, isobaric tags for relative and absolute quantitation (iTRAQ), was employed to screen the proteins regulated by β-elemene pretreatment prior to ionizing radiation (IR) in SGC7901 gastric cancer cell line. IPA-3 was used as a specific small molecule inhibitor of p21-activated protein kinase 1 (Pak1) to target Pak1 signaling. Protein levels of PAK1IP1 (p21-activated protein kinase-interacting protein 1), total Pak1 (t-Pak1), phospho-Pak1 (T423), phospho-ERK1/2 (Thr202/Tyr204), and cleaved caspase-3 (17 kDa) were assessed by western blotting.

RESULTS: MKN45 and SGC7901 gastric cancer cell lines were relatively more resistant to IR. β-elemene pretreatment decreased clonogenic survival following IR in MKN45 and SGC7901 gastric cancer cell lines. Additionally, β-elemene pretreatment prior to IR increased radiation-induced cell death compared with IR alone in MKN45 (10.4% ± 0.9% vs 34.8% ± 2.8%, P < 0.05) and SGC7901 (11.6% ± 0.9% vs 46.7% ± 5.2%, P < 0.05) human gastric cancer cell lines, respectively, consistent with the level of cleaved caspase-3 (17 kDa). Through iTRAQ analysis and western blot validation, we found that β-elemene upregulated PAK1IP1 and downregulated phospho-Pak1 (T423) and phospho-ERK1/2 in SGC7901 gastric cancer cells. IR increased the level of phospho-Pak1 (T423). Pretreatment with β-elemene decreased radiation-induced Pak1 and ERK1/2 phosphorylation. Inhibition of Pak1 using IPA-3 decreased clonogenic survival following IR. In addition, IPA-3 increased radiation-induced cell death in MKN45 (13.4% ± 0.3% vs 26.6% ± 1.0%, P < 0.05) and SGC7901 (16.0% ± 0.6% vs 37.3% ± 1.7%, P < 0.05) gastric cancer cell lines, respectively, consistent with the level of cleaved caspase-3 (17 kDa). Western blotting showed that IPA-3 decreased radiation-induced Pak1 and ERK1/2 phosphorylation.

CONCLUSION: This is the first demonstration that β-elemene enhances radiosensitivity of gastric cancer cells, and that the mechanism involves inhibition of Pak1 signaling.

Radiation-induced dose-dependent changes of the spleen following postoperative chemoradiotherapy for gastric cancer

BACKGROUND AND PURPOSE

Abdominal (chemo-)radiotherapy is associated with dose-limiting toxicity of various normal structures. The purpose of this retrospective study was to investigate radiation-induced changes of the spleen and their clinical consequences.

PATIENTS AND METHODS

In gastric cancer patients treated with postoperative chemoradiotherapy, the spleen size and its functions were assessed at follow-up by spleen volume on CT-scan, serum leucocytes/thrombocytes, and the occurrence of infectious events consisting of pneumonia and fatal sepsis. To evaluate the effect of radiation dose, mixed effects and Cox regression models were used.

RESULTS

Forty-six out of 90 consecutive patients treated from 2006 to 2011 were evaluable. All patients received 45 Gy in 25 fractions with concurrent capecitabine (n=8), and capecitabine/cisplatin (n=38). Median Dmean to the spleen was 40 Gy (range 32-46). Mean relative spleen volume reduced to 37% (95% CI 32-42%) at 4-year follow-up, which was most strongly associated to the V44 (p<0.001). Median follow-up time was 67 (95% CI 57-78) months. Eleven patients had 13 pneumonias and 3 fatal sepsis. No association with dosimetric parameters was observed.

CONCLUSIONS

In postoperative chemoradiotherapy for gastric cancer, the spleen received a high radiation dose. This resulted in a progressive, radiation dose-dependent reduction of spleen volume. Pneumonia and fatal sepsis occurred frequently, possibly as a result of functional hyposplenia.

Double-arc volumetric modulated therapy improves dose distribution compared to static gantry IMRT and 3D conformal radiotherapy for adjuvant therapy of gastric cancer

BACKGROUND

The objective of this study was to compare the dose distributions of RapidArc (RA), static gantry intensity-modulated radiotherapy (IMRT), and three-dimensional conformal radiotherapy (3DCRT) as adjuvant radiotherapy modalities for the treatment of gastric cancer.

METHODS

Fifteen patients with gastric cancer that underwent limited lymphadenectomy of perigastric lymph nodes were included in this study. Dosimetric values for a total dose of 45 Gy (1.8 Gy/day) were calculated for the RapidArc, IMRT, and 3DCRT modalities. The following parameters were compared: D99%, D1%, V95%, V107%, and conformity and homogeneity index values (CI and HI, respectively) for the planned target volume (PTV). Dose volume histogram (DVH) and dose distribution of the organs at risk (OAR), as the maximal dose to the spinal cord, V30 and V40 of the small bowel, and V20, V30 of liver and kidney were also assessed respectively.

RESULTS

RA, IMRT, and 3DCRT all achieved desirable PTV coverage. However, RA and IMRT significantly decreased D1% and V107%, and provided better CI and HI values compared with 3DCRT (P <0.05). Moreover, RA also achieved a significantly lower maximum dose for the spinal cord, liver V30, and kidney V20 compared to IMRT and 3DCRT; while the mean dose for these three organ types did not differ for the RA, IMRT, and 3DCRT plans.

CONCLUSIONS

Both RA and IMRT achieved favorable PTV coverage compared to 3DCRT. In addition, RA achieved better dosimetry than IMRT and 3DCRT, and provided better protection for the spinal cord, liver, and kidneys.

Image-guided intensity-modulated radiotherapy for patients with locally advanced gastric cancer: a clinical feasibility study

BACKGROUND

The aim of this study was to determine the medical and technical feasibility of intensity-modulated radiotherapy (IMRT) in high-risk nonmetastatic gastric cancer stage II and III after primary gastrectomy and D2 lymphadenectomy.

METHODS AND MATERIALS

A prospective nonrandomized phase II trial was performed on 25 consecutive patients with gastric cancer with high risk (T3-4, N1-3, G2-3, R0-1). The dose delivered was 45 Gy (1.80 Gy per fraction) in IMRT technique. Concurrent 5-fluorouracil-based chemotherapy at 225 mg/m(2) was administered as a continuous intravenous infusion. Primary endpoints were acute gastrointestinal toxicity (CTC 4.0) and technical feasibility of IMRT in regard to dose planning and radiation delivery.

RESULTS

Early acute events were defined as clinical and chemical adverse effects of IMRT and concurrent chemotherapy during treatment. By definition, 90 days after the end of IMRT has been evaluated as acute-phase toxicity. No patient had grade 4 or higher acute adverse events. Clinical grade 3 toxicity occurred in two patients (8%) with diarrhea and in one case (4%) with nausea. Hematological changes with grade 3 occurred in three cases (12%) with hemoglobin decrease, in five cases (25%) as leukopenia, and in one case (4%) with thrombocytopenia. The mean dose for liver was 16 Gy and the percentage volume exceeding 30 Gy (V30) was 21%. Mean dose for right and left kidney was 9 and 13 Gy, respectively, and V20 was 9% and 13%, respectively. Heart received a median dose of 15 Gy and V40 was 17%. The mean dose to the bowel was 11 Gy and V40 was 6%. Spinal cord had at maximum 33 Gy in median. Specifics of dose distribution, including the coverage, for the target region were as follows: minimum was 33 Gy, maximum 48.6 Gy, and mean dose 44.6 Gy. The prescribed dose (45 Gy) covered 99% and 95% of planning target volume (OTV) in 66% and 92% of cases, respectively. Median PTV was 15.77 ml (range, 805-3,604 ml).

CONCLUSIONS

The data support the practical feasibility of IMRT in adjuvant treatment in high-risk gastric cancer in the postoperative setting as a proof of principle. Acute toxicity has been tolerable.

Dose-dependent changes in renal (1)H-/(23)Na MRI after adjuvant radiochemotherapy for gastric cancer

PURPOSE

Combined radiochemotherapy (RCT) for gastric cancer with three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to the upper left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) allows kidney sparing despite improved target coverage. Renal function in long-term gastric cancer survivors was evaluated with 3T functional magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) and (23)Na imaging.

PATIENTS AND METHODS

Five healthy volunteers and 13 patients after radiotherapy were included: 11×IG-IMRT; 1×3D-CRT; 1× "positive control" with stereotactic body radiotherapy (SBRT) of a metastasis between the spleen/left kidney. Radiation doses were documented for the upper/middle/lower kidney subvolumes. Late toxicity was evaluated based on CTC criteria, questionnaire, and creatinine values. Morphological sequences, DWI images, and (23)Na images were acquired using a (1)H/(23)Na-tuned body-coil before/after intravenous water load (WL). Statistics for [(23)Na] (concentration) and apparent diffusion coefficient (ADC) values were calculated for upper/middle/lower renal subvolumes. Corticomedullary [(23)Na] gradients and [(23)Na] differences after WL were determined.

RESULTS

No major morphological alteration was detected in any patient. Minor scars were observed in the cranial subvolume of the left kidney of the 3D-CRT and the whole kidney of the control SBRT patient. All participants presented a corticomedullary [(23)Na] gradient. After WL, a significant physiological [(23)Na] gradient decrease (p < 0.001) was observed in all HV and IG-IMRT patients. In the cranial left kidney of the 3D-CRT patient and the positive control SBRT patient, the decrease was nonsignificant (p = 0.01, p = 0.02). ADC values were altered nonsignificantly in all renal subvolumes (all participants). Renal subvolumes with doses ≥ 35 Gy showed a reduced change of the [(23)Na] gradient after WL (p = 0.043). No participants showed clinical renal impairment.

CONCLUSIONS

Functional parameters of renal (23)Na MRI after gastric IG-IMRT are identical to those of healthy volunteers, in contrast to renal subvolumes after ablative doses in the control and 3D-CRT patient. While kidney doses to the cortex below 20-25 Gy in fractional doses of ~ 1 Gy in IG-IMRT (combined with intensified chemotherapy) do not seem to cause significant MRI morphological or functional alterations, doses of > 35 Gy in 1.5-2 Gy fractions clearly result in impairment.

Renal remodeling after abdominal radiation therapy: parenchymal and functional changes

OBJECTIVE

The purpose of this study was to quantify changes in renal length, volume, and function over time after upper abdominal radiation therapy.

MATERIALS AND METHODS

Imaging and clinical data were retrospectively reviewed for 27 adults with abdominal radiation therapy between 2001 and 2012. All had two kidneys, radiation exposure to one kidney, and survival of at least 1 year after therapy. Mean prescribed dose was 52 ± 9 Gy to extrarenal targets. Length and volume of exposed and unexposed kidneys were measured on CT scans before treatment (baseline) and at intervals 0-3, 3-6, 6-12, 12-24, 24-36, and more than 36 months after completion of radiotherapy. Serum creatinine was correlated at each interval. Mixed-models ANOVA was used to test renal length and volume, serum creatinine, and time against multiple models to assess for temporal effects; specific time intervals were compared in pairwise manner.

RESULTS

Mean follow-up duration was 35 months (range, 5-94 months). Exposed kidney length and volume progressively decreased from baseline throughout follow-up, with mean loss of 23% (p < 0.001) and 47% (p < 0.001), respectively. Slight increase in unexposed kidney length was not significant. Mean serum creatinine increased from 0.86 ± 0.18 mg/dL at baseline to 1.12 ± 0.27 mg/dL at 12-24 months (p < 0.001), then stabilized.

CONCLUSION

Kidneys exposed to radiation during therapy of adjacent malignancies exhibited continuous progressive atrophy for the entire follow-up period, nearly 8 years. Volume changes were twice as great as length changes. Renal function also declined. To accurately interpret follow-up studies in cancer survivors, radiologists should be aware of the potential for progressive renal atrophy, even many years after radiation therapy.

Proton therapy in adjuvant treatment of gastric cancer: planning comparison with advanced x-ray therapy and feasibility report

BACKGROUND

Adjuvant chemoradiotherapy improves both overall- and relapse-free survival in patients with resected gastric cancer. However, this comes at the cost of increased treatment-related toxicity. Proton therapy (PT) has distinct dosimetric characteristics that may reduce dose to normal tissues, improving the therapeutic ratio. The purpose of this treatment planning study is to compare PT and intensity-modulated x-ray therapy (IMXT) in gastric cancer with regards to normal tissue sparing.

MATERIAL AND METHODS

The patient population consisted of resected gastric cancer patients treated at a single institution between 2008 and 2013. Patients who had undergone 4D CT simulation were replanned to the originally delivered doses (45-54 Gy in 25-30 daily fractions) using six-field photon IMXT and 2-3-field PT (double scattering-uniform scanning techniques).

RESULTS

Thirteen patients were eligible for the planning comparison. IMXT provided slightly higher homogeneity indices (median values 0.04 ± 0.01 vs. 0.07 ± 0.01, p = 0.03). PT resulted in significantly (p < 0.05) lower intermediate-low doses for all the normal tissues examined (small bowel V15 82 ml vs. 133 ml, liver mean doses Gy 11.9 vs. 14.4 Gy, left/right kidney mean doses 5/0.9 Gy vs. 7.8/3.1 Gy, heart mean doses 7.4 Gy vs. 9.5 Gy). The total energy deposited outside the target volume was significantly lower with PT (median integral dose 90.1 J vs. 129 J). Four patients were treated with PT: treatment was feasible and verifications scans showed that target coverage was robust.

CONCLUSION

PT can contribute to normal tissue sparing in the adjuvant treatment of gastric cancer, with a potential benefit in terms of compliance to treatment, acute and late toxicities.

Dosimetric comparison of intensity modulated and volumetric arc radiation therapy for gastric cancer

The aim of the present study was to compare radiotherapy treatment plans for gastric cancer using intensity-modulated radiotherapy (IMRT) and single/double-arc volumetric modulated arc therapy (SA/DA-VMAT) delivery techniques. A total of 29 postoperative gastric cancer patients were enrolled in this study and each patient was scheduled 5-field IMRT (5F-IMRT), 7-field IMRT (7F-IMRT), SA-VMAT and DA-VMAT techniques. Dose-volume histogram statistics, conformal index (CI), homogeneity index (HI) and monitor units (MUs) were analyzed to compare treatment plans. The DA-VMAT plans exceeded the other three methods in terms of planning tumor volume dose and organs at risk in the kidneys, but not in the liver. DA-VMAT exhibited a better mean CI (0.87±0.03) and HI (0.10±0.01) than the other techniques. In addition, for the kidneys the dose sparing (V13, V18 and mean kidney dose) was improved by DA-VMAT plans. Similar results were observed for MUs. However, 5F-IMRT showed a marginal advantage in V30 and mean dose in normal liver when compared with DA-VMAT. The results of this study suggest that DA-VMAT provides improved tumor coverage when compared with 5F-IMRT, 7F-IMRT and SA-VMAT; however, DA-VMAT exhibits no advantage in liver protection when compared with 5F-IMRT. Further studies are required to establish differences in treatment outcomes among the four technologies.

A comprehensive dosimetric study of pancreatic cancer treatment using three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), volumetric-modulated radiation therapy (VMAT), and passive-scattering and modulated-scanning proton therapy (PT)

With traditional photon therapy to treat large postoperative pancreatic target volume, it often leads to poor tolerance of the therapy delivered and may contribute to interrupted treatment course. This study was performed to evaluate the potential advantage of using passive-scattering (PS) and modulated-scanning (MS) proton therapy (PT) to reduce normal tissue exposure in postoperative pancreatic cancer treatment. A total of 11 patients with postoperative pancreatic cancer who had been previously treated with PS PT in University of Pennsylvania Roberts Proton Therapy Center from 2010 to 2013 were identified. The clinical target volume (CTV) includes the pancreatic tumor bed as well as the adjacent high-risk nodal areas. Internal (iCTV) was generated from 4-dimensional (4D) computed tomography (CT), taking into account target motion from breathing cycle. Three-field and 4-field 3D conformal radiation therapy (3DCRT), 5-field intensity-modulated radiation therapy, 2-arc volumetric-modulated radiation therapy, and 2-field PS and MS PT were created on the patients' average CT. All the plans delivered 50.4Gy to the planning target volume (PTV). Overall, 98% of PTV was covered by 95% of the prescription dose and 99% of iCTV received 98% prescription dose. The results show that all the proton plans offer significant lower doses to the left kidney (mean and V18Gy), stomach (mean and V20Gy), and cord (maximum dose) compared with all the photon plans, except 3-field 3DCRT in cord maximum dose. In addition, MS PT also provides lower doses to the right kidney (mean and V18Gy), liver (mean dose), total bowel (V20Gy and mean dose), and small bowel (V15Gy absolute volume ratio) compared with all the photon plans and PS PT. The dosimetric advantage of PT points to the possibility of treating tumor bed and comprehensive nodal areas while providing a more tolerable treatment course that could be used for dose escalation and combining with radiosensitizing chemotherapy.

Clinical outcomes for gastric cancer following adjuvant chemoradiation utilizing intensity modulated versus three-dimensional conformal radiotherapy

PURPOSE/OBJECTIVES

To determine if intensity modulated radiation therapy (IMRT) in the post-operative setting for gastric cancer was associated with reduced toxicity compared to 3D conformal radiation therapy (3DCRT).

MATERIALS/METHODS

This retrospective study includes 24 patients with stage IB-IIIB gastric cancer consecutively treated from 2001-2010. All underwent surgery followed by adjuvant chemoradiation. Concurrent chemotherapy consisted of 5-FU/leucovorin (n = 21), epirubicin/cisplatin/5FU (n = 1), or none (n = 2). IMRT was utilized in 12 patients and 3DCRT in 12 patients. For both groups, the target volume included the tumor bed, anastomosis, gastric stump, and regional lymphatics.

RESULTS

Median follow-up for the entire cohort was 19 months (range 0.4-8.5 years), and 49 months (0.5-8.5 years) in surviving patients. The 3DCRT group received a median dose of 45 Gy, and the IMRT group received a median dose of 50.4 Gy (p = 0.0004). For the entire cohort, 3-year overall survival (OS) was 40% and 3-year disease free survival (DFS) was 41%. OS and DFS did not differ significantly between the groups. Acute toxicity was similar. Between 3DCRT and IMRT groups, during radiotherapy, median weight lost (3.2 vs. 3.3 kg, respectively; p = 0.47) and median percent weight loss were similar (5.0% vs. 4.3%, respectively; p = 0.43). Acute grade 2 toxicity was experienced by 8 patients receiving 3DCRT and 11 receiving IMRT (p = 0.32); acute grade 3 toxicity occurred in 1 patient receiving 3DCRT and none receiving IMRT (p = 1.0). No patients in either cohort experienced late grade 3 toxicity, including renal or gastrointestinal toxicity. At last follow up, the median increase in creatinine was 0.1 mg/dL in the IMRT group and 0.1 mg/dL in the 3DCRT group (p = 0.78).

CONCLUSION

This study demonstrates that adjuvant chemoradiation for gastric cancer with IMRT to 50.4 Gy was well-tolerated and compared similarly in toxicity with 3DCRT to 45 Gy.

Basal renal function reserve and mean kidney dose predict future radiation-induced kidney injury in stomach cancer patients

BACKGROUND

Adjuvant chemoradiotherapy (CRT) improves the survival in patients with locally advanced stomach cancer. The kidneys are the major dose-limiting organs for radiotherapy (RT) in upper abdominal cancers. We aimed to evaluate the impact of adjuvant CRT on renal function of patients with stomach cancer.

MATERIAL AND METHODS

Fifty-nine stomach cancer patients who underwent postoperative CRT were included. Demographic parameters (age, gender), and basal and 12th-month biochemical parameters were recorded. Mean kidney dose (MKD) administered was determined. Estimated glomerular filtration rate (eGFR) was calculated by modification of diet in renal disease formula.

RESULTS

Fifty-nine patients were recruited (age 60.8 ± 11.9 years; female/male 25/34; follow-up duration 15.6 ± 9.8 months). Twenty-one patients (35.6 %) had basal eGFR <90 ml/min/1.73 m(2). When the basal and 12th-month eGFR was compared, eGFR decreased in 27 patients (45.8 %), whereas eGFR remained stable in 32 (54.2 %) patients. Cox regression analyses revealed that a MKD ≥1,500 cGy and basal eGFR <90 ml/min/1.73 m(2) significantly increased the risk of a decreased eGFR at 12th month (HR = 2.288, 95 % CI 1.009-5.188, p = 0.048 and HR = 2.854, 95 % CI 1.121-7.262, p = 0.028, respectively).

CONCLUSION

MKD ≥1,500 cGy and a basal eGFR <90 ml/min/1.73 m(2) significantly increased the risk of a decreased eGFR at 12th month. We suggest that patients with stomach cancer be evaluated for their basal renal reserve prior to RT, and it may be more convenient to further minimize the dose to the kidneys with more sophisticated RT techniques in patients with stomach cancer, more specifically in patients with decreased renal reserve.

Radiotherapy of abdomen with precise renal assessment with SPECT/CT imaging (RAPRASI): design and methodology of a prospective trial to improve the understanding of kidney radiation dose response

Background

The kidneys are a principal dose-limiting organ in radiotherapy for upper abdominal cancers. The current understanding of kidney radiation dose response is rudimentary. More precise dose-volume response models that allow direct correlation of delivered radiation dose with spatio-temporal changes in kidney function may improve radiotherapy treatment planning for upper-abdominal tumours.

Our current understanding of kidney dose response and tolerance is limited and this is hindering efforts to introduce advanced radiotherapy techniques for upper-abdominal cancers, such as intensity-modulated radiotherapy (IMRT). The aim of this study is to utilise radiotherapy and combined anatomical/functional imaging data to allow direct correlation of radiation dose with spatio-temporal changes in kidney function. The data can then be used to develop a more precise dose-volume response model which has the potential to optimise and individualise upper abdominal radiotherapy plans.

Methods/design

The Radiotherapy of Abdomen with Precise Renal Assessment with SPECT/CT Imaging (RAPRASI) is an observational clinical research study with participating sites at Sir Charles Gairdner Hospital (SCGH) in Perth, Australia and the Peter MacCallum Cancer Centre (PMCC) in Melbourne, Australia. Eligible patients are those with upper gastrointestinal cancer, without metastatic disease, undergoing conformal radiotherapy that will involve incidental radiation to one or both kidneys. For each patient, total kidney function is being assessed before commencement of radiotherapy treatment and then at 4, 12, 26, 52 and 78 weeks after the first radiotherapy fraction, using two procedures: a Glomerular Filtration Rate (GFR) measurement using the ⁵¹Cr-ethylenediamine tetra-acetic acid (EDTA) clearance; and a regional kidney perfusion measurement assessing renal uptake of ^99mTc-dimercaptosuccinic acid (DMSA), imaged with a Single Photon Emission Computed Tomography / Computed Tomography (SPECT/CT) system. The CT component of the SPECT/CT provides the anatomical reference of the kidney’s position. The data is intended to reveal changes in regional kidney function over the study period after the radiotherapy. These SPECT/CT scans, co-registered with the radiotherapy treatment plan, will provide spatial correlation between the radiation dose and regional renal function as assessed by SPECT/CT. From this correlation, renal response patterns will likely be identified with the purpose of developing a predictive model.

Trial registration

Australian New Zealand Clinical Trials Registry: ACTRN12609000322235

(Neo)-adjuvant chemo(-radio) therapy for adenocarcinomas of the gastroesophageal junction and the stomach in the West

Worldwide, the treatment of adenocarcinomas of the gastroesophageal junction and stomach has changed over the past decades. It is no longer surgery alone. Nowadays, most patients undergo surgery plus pre- and/or postoperative therapies. However, there are still marked differences in surgical procedures between the East and the West which might influence the surgical prognosis and thereby also the choice of perioperative treatment strategies. In the East, with its more extended surgical procedures, including standard D2 dissections, the current treatment philosophy is primary surgery followed by adjuvant chemotherapy. Neoadjuvant approaches are restricted to really advanced tumors, and perioperative chemoradiation is not routinely used (at least to date). This clearly differs from treatment strategies currently recommended in Western countries. In Europe and North America, pre- plus postoperative chemotherapy has become the recommended treatment for locally more advanced tumors, and preoperative chemoradiation is increasingly administered to patients with adenocarcinomas of the gastroesophageal junction (Siewert type I/II). However, the role of postoperative chemotherapy (despite its increasing use) is still under discussion in the West (especially Europe) and not generally recommended/accepted as a standard treatment. Postoperative chemoradiation, which is one standard treatment in North America, is only regarded as a treatment option for patients after 'inadequate surgery' (i.e. <D2 dissection) in many European countries.

Can adjuvant chemoradiotherapy replace extended lymph node dissection in gastric cancer?

Surgical resection remains the essential part in the curative treatment of gastric cancer. However, with surgery only, long-term survival is poor (5-year survival <25 % in Europe). Randomized studies, which compared limited (D1) lymph node dissection with more extended (D2) resections in the Western world, failed to show a survival benefit for more extensive surgery. A substantial increase in survival was found with perioperative chemotherapy in the MAGIC study. In addition, the SWOG/Intergroup 0116 study showed that postoperative chemoradiotherapy (CRT) prolonged 5-year overall survival compared to surgery only. However, it has been argued that surgical undertreatment undermined survival in this trial. In a randomized Korean study, patients with advanced stage gastric cancer who received postoperative CRT had better outcome after a D2 dissection. At our institute phase I-II studies with adjuvant cisplatin and capecitabine-based CRT have been performed in over 120 patients with resected gastric cancer. Retrospective comparison of patients treated in these studies with those that had surgery only in the D1D2 study, demonstrated that postoperative CRT was associated with better outcome, especially after D1 or a R1 resection. For daily practice, it remains unclear whether patients after optimal (D2) gastric surgery will benefit from postoperative CRT. This is currently being tested in prospective randomized phase III trials (CRITICS; TOPGEAR).

Adjuvant IMRT/XELOX radiochemotherapy improves long-term overall- and disease-free survival in advanced gastric cancer

PURPOSE

In a retrospective analysis, adjuvant intensity-modulated radiation therapy (IMRT) combined with modern chemotherapy improved advanced gastric cancer survival rates compared to a combination of three-dimensional conformal radiation therapy (3D-CRT) and conventional chemotherapy. We report on the long-term outcomes of two consecutive patient cohorts that were treated with either IMRT and intensive chemotherapy, or 3D-CRT and conventional chemotherapy.

PATIENTS AND METHODS

Between 2001 and 2008, 65 consecutive gastric cancer patients received either 3D-CRT (n = 27) or IMRT (n = 38) following tumor resection. Chemotherapy comprised predominantly 5-fluorouracil/folinic acid (5-FU/FA) in the earlier cohort and capecitabine plus oxaliplatin (XELOX) in the latter. The primary endpoints were overall survival (OS) and disease-free survival (DFS).

RESULTS

Median OS times were 18 and 43 months in the 3D-CRT and IMRT groups, respectively (p = 0.0602). Actuarial 5-year OS rates were 26 and 47  %, respectively. Within the IMRT group, XELOX gave better results than 5-FU/FA in terms of OS, but this difference was not statistically significant. The primary cause of death in both groups was distant metastasis. Median DFS times were 14 and 35 months in the 3D-CRT and IMRT groups, respectively (p = 0.0693). Actuarial 5-year DFS rates were 22 and 44  %, respectively. Among patients receiving 5-FU/FA, DFS tended to be better in the IMRT group, but this was not statistically significant. A similar analysis for the XELOX group was not possible as 3D-CRT was almost never used to treat these patients. No late toxicity exceeding grade 3 or secondary tumors were observed.

CONCLUSION

After a median follow-up period of over 5 years, OS and DFS were improved in the IMRT/XELOX treated patients compared to the 3D-CRT/5-FU/FA group. Long-term observation revealed no clinical indications of therapy-induced secondary tumors or renal toxicity.

Radiotherapy for tumors of the stomach and gastroesophageal junction--a review of its role in multimodal therapy

There is broad consensus on surgical resection being the backbone of curative therapy of gastric- and gastroesophageal junction carcinoma. Nevertheless, details on therapeutic approaches in addition to surgery, such as chemotherapy, radiotherapy or radiochemotherapy are discussed controversially; especially whether external beam radiotherapy should be applied in addition to chemotherapy and surgery is debated in both entities and differs widely between regions and centers. Early landmark trials such as the Intergroup-0116 and the MAGIC trial must be interpreted in the context of potentially insufficient lymph node resection. Despite shortcomings of both trials, benefits on overall survival by radiochemotherapy and adjuvant chemotherapy were confirmed in populations of D2-resected gastric cancer patients by Asian trials.

Recent results on junctional carcinoma patients strongly suggest a survival benefit of neoadjuvant radiochemotherapy in curatively resectable patients. An effect of chemotherapy in the perioperative setting as given in the MAGIC study has been confirmed by the ACCORD07 trial for junctional carcinomas; however both the studies by Stahl et al. and the excellent outcome in the CROSS trial as compared to all other therapeutic approaches indicate a superiority of neoadjuvant radiochemotherapy as compared to perioperative chemotherapy in junctional carcinoma patients. Surgery alone without neoadjuvant or perioperative therapy is considered suboptimal in patients with locally advanced disease.

In gastric carcinoma patients, perioperative chemotherapy has not been compared to adjuvant radiochemotherapy in a randomized setting. Nevertheless, the results of the recently published ARTIST trial and the Chinese data by Zhu and coworkers, indicate a superiority of adjuvant radiochemotherapy as compared to adjuvant chemotherapy in terms of disease free survival in Asian patients with advanced gastric carcinoma. The ongoing CRITICS trial is supposed to provide reliable conclusions about which therapy should be preferred in Western patients with gastric carcinoma. If radiotherapy is performed, modern approaches such as intensity-modulated radiotherapy and image guidance should be applied, as these methods reduce dose to organs at risk and provide a more homogenous coverage of planning target volumes.

Assessment of renal function after conformal radiotherapy and intensity-modulated radiotherapy by functional 1H-MRI and 23Na-MRI

PURPOSE

Adjuvant radiochemotherapy (RCHT) improves survival of patients with locally advanced gastric cancer. Conventional three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to a significant amount of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides excellent target coverage with improved kidney sparing. Few long-term results on IMRT for gastric cancer, however, have been published. Functional magnetic resonance imaging (fMRI) at 3.0 T including blood oxygenation-level dependent (BOLD) imaging, diffusion-weighted imaging (DWI) and, for the first time, (23)Na imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT.

PATIENTS AND METHODS

Four disease-free patients (2 after 3D-CRT and 2 after IMRT; FU for all patients > 5 years) were included in this feasibility study. Morphological sequences, axial DWI images, 2D-gradient echo (GRE)-BOLD images, and (23)Na images were acquired. Mean values/standard deviations for ((23)Na), the apparent diffusion coefficient (ADC), and R2* values were calculated for the upper/middle/lower parts of both kidneys. Corticomedullary (23)Na-concentration gradients were determined.

RESULTS

Surprisingly, IG-IMRT patients showed no morphological alterations and no statistically significant differences of ADC and R2* values in all renal parts. Values for mean corticomedullary (23)Na-concentration matched those for healthy volunteers. Results were similar in 3D-CRT patients, except for the cranial part of the left kidney. This was atrophic and presented significantly reduced functional parameters (p = 0.001-p = 0.033). Reduced ADC values indicated reduced cell density and reduced extracellular space. Cortical and medullary R2* values of the left cranial kidney in the 3D-CRT group were higher, indicating more deoxygenated hemoglobin due to reduced blood flow/oxygenation. ((23)Na) of the renal cranial parts in the 3D-CRT group was significantly reduced, while the expected corticomedullary (23)Na-concentration gradient was partially conserved.

CONCLUSIONS

Functional MRI can assess postradiotherapeutic renal changes. As expected, marked morphological/functional effects were observed in high-dose areas (3D-CRT), while, unexpectedly, no alteration in kidney function was observed in IG-IMRT patients, supporting the hypothesis that reducing total/fractional dose to the renal parenchyma by IMRT is clinically beneficial.

Quality Research in Radiation Oncology analysis of clinical performance measures in the management of gastric cancer

BACKGROUND

The specific aim was to determine national patterns of radiation therapy (RT) practice in patients treated for stage IB-IV (nonmetastatic) gastric cancer (GC).

METHODS AND MATERIALS

A national process survey of randomly selected US RT facilities was conducted which retrospectively assessed demographics, staging, geographic region, practice setting, and treatment by using on-site record review of eligible GC cases treated from 2005 to 2007. Three clinical performance measures (CPMs), (1) use of computed tomography (CT)-based treatment planning; (2) use of dose volume histograms (DVHs) to evaluate RT dose to the kidneys and liver; and (3) completion of RT within the prescribed time frame; and emerging quality indicators, (i) use of intensity modulated RT (IMRT); (ii) use of image-guided tools (IGRT) other than CT for RT target delineation; and (iii) use of preoperative RT, were assessed.

RESULTS

CPMs were computed for 250 eligible patients at 45 institutions (median age, 62 years; 66% male; 60% Caucasian). Using 2000 American Joint Committee on Cancer criteria, 13% of patients were stage I, 29% were stage II, 32% were stage IIIA, 10% were stage IIIB, and 12% were stage IV. Most patients (43%) were treated at academic centers, 32% were treated at large nonacademic centers, and 25% were treated at small to medium sized facilities. Almost all patients (99.5%) underwent CT-based planning, and 75% had DVHs to evaluate normal tissue doses to the kidneys and liver. Seventy percent of patients completed RT within the prescribed time frame. IMRT and IGRT were used in 22% and 17% of patients, respectively. IGRT techniques included positron emission tomography (n=20), magnetic resonance imaging (n=1), respiratory gating and 4-dimensional CT (n=22), and on-board imaging (n=10). Nineteen percent of patients received preoperative RT.

CONCLUSIONS

This analysis of radiation practice patterns for treating nonmetastatic GC indicates widespread adoption of CT-based planning with use of DVH to evaluate normal tissue doses. Most patients completed adjuvant RT in the prescribed time frame. IMRT and IGRT were not routinely incorporated into clinical practice during the 2005-2007 period. These data will be a benchmark for future Quality Research in Radiation Oncology GC surveys.

The TGF-β co-receptor endoglin regulates macrophage infiltration and cytokine production in the irradiated mouse kidney

BACKGROUND AND PURPOSE

We previously showed that mice with reduced levels of the transforming growth factor-beta (TGF-β) co-receptor endoglin (Eng(+/-) mice) develop less fibrosis and vascular damage after kidney irradiation than their wild type (Eng(+/+) mice) littermates; however, the underlying mechanism was unclear. Results from current studies suggest that this occurs via modulation of the radiation-induced inflammatory response.

MATERIALS AND METHODS

Kidneys of Eng(+/+) and Eng(+/-) mice were irradiated with 16Gy. Mice were sacrificed at 20weeks after irradiation and gene expression and protein levels were analyzed.

RESULTS

Kidney irradiation triggered the infiltration of macrophages in both Eng(+/+) and Eng(+/-) mice, however, levels of macrophage-produced cytokines interleukin 1 beta (Il1b) and interleukin 6 (Il6) were reduced in irradiated Eng(+/-) compared to Eng(+/+) mice. Double immuno-stainings confirmed that IL-6 was produced by macrophages, whereas IL-1β was mainly detected in other cell types. Accordingly, inflammatory cell precursors derived from the bone marrow of Eng(+/-) mice showed impaired ability to express Il1b and Il6 compared to wild type mice.

CONCLUSIONS

Endoglin promotes kidney inflammation after irradiation by regulating macrophage infiltration and interleukin production, thereby promoting pathogenic changes after radiation exposure.

Association of Technetium(99m) MAG-3 renal scintigraphy with change in creatinine clearance following chemoradiation to the abdomen in patients with gastrointestinal malignancies

BACKGROUND

Information on differential renal function following abdominal chemoradiation is limited. This study evaluated the association between renal function as measured by biochemical endpoints and scintigraphy and dose volume parameters in patients with gastrointestinal malignancies.

MATERIALS AND METHODS

Patients who received abdominal chemoradiation between 2002 and 2009 were identified for this study. Technetium(99m) MAG-3 scintigraphy and laboratory data were obtained prior to and after chemoradiation in 6 month intervals. Factors assessed included age, gender, hypertension, diabetes, and dose volume parameters. Renal function was assessed by biochemical endpoints and renal scintigraphy.

RESULTS

Significant reductions in relative renal function of the primarily irradiated kidney and creatinine clearance were seen. Split renal function decreased from 49.75% pre-radiation to 47.74% and 41.28% at 6-12 months and >12 months post-radiation (P=0.0184). Creatinine clearance declined from 90.67ml/min pre-radiation to 82.23ml/min and 74.54ml/min at 6-12 months and >12 months post-radiation (P<0.0001). Univariate analysis of patients who had at least one post-radiation renogram showed the percent volumes of the primarily irradiated kidney receiving ≥ 25 Gy (V(25)) and 40 Gy (V(40)) were significantly associated with ≥5% decrease in relative renal function (P=0.0387 and P=0.0438 respectively).

CONCLUSION

Decline in split renal function using Technetium(99m) MAG-3 scintigraphy correlates with decrease in creatinine clearance and radiation dose-volume parameters following abdominal chemoradiation. Change in split perfusion can be detected as early as 6 months post-radiation. Scintigraphy may provide early determination and quantification of subclinical renal injury prior to clinical evidence of nephropathy.

[Functional magnetic resonance imaging for evaluation of radiation-induced renal damage]

The diagnosis of radiation-induced (especially chronic) renal alterations/damage is difficult and currently relies primarily on clinical evaluation. The importance of renal diagnostic evaluation will increase continuously due to the increasing number of long-term survivors after radiotherapy. This article evaluates the potentia diagnostic contribution of magnetic resonance (MR) imaging with a focus on functional MRI. The following functional MRI approaches are briefly presented and evaluated: blood oxygenation level-dependent imaging (BOLD), diffusion-weighted imaging (DWI) or diffusion tensor imaging (DTI), MR perfusion measurements and (23)Na imaging. In summary, only DWI and contrast-enhanced MR perfusion currently seem to be suitable approaches for a broader, clinical implementation. However, up to now valid data from larger patient studies are lacking for both techniques in regard to radiation-induced renal alterations. The BOLD and (23)Na imaging procedures have a huge potential but are currently neither sufficiently evaluated with regard to radiation-induced renal alterations nor technically simple and reliable for implementation into the clinical routine.

[Radiation-induced nephropathy]

BACKGROUND

The kidneys are dose-limiting organs when total body irradiation or irradiation of the digestive tract is planned. The incidence of radiation-induced toxicity is probably underestimated due to its latency and confounding factors like chemotherapy.

MATERIAL AND METHODS

A search of the literature for radiation induced renal toxicity was performed.

RESULTS

Most toxicities occur around 18 months. Renal mobility is significant in terms of dosimetric consequences, in particular in the young child. In case of total body irradiation, the dose responsible for a 5% risk of toxicities is around 16 Gy in 2 Gy fractions over 2 weeks. For partial renal irradiation, the volume receiving 20 Gy should be below 32% of the total renal volume. Compensatory mechanisms remain possible in areas receiving 12 Gy or less in 1 Gy fractions. When nephrotoxic chemotherapy, these tolerance doses must be lowered. Treatment of radiation-induced nephropathy may include ACE inhibitors.

DISCUSSION/CONCLUSION

Prospective assessment of dose-volume histograms and consideration of renal mobility in treatment plans along with improving radiation techniques should help to improve treatment plans including the kidneys.

Treatment of resectable gastric cancer

Stomach cancer is one of the most common cancers worldwide, despite its declining overall incidence. Although there are differences in incidence, etiology and pathological factors, most studies do not separately analyze cardia and noncardia gastric cancer. Surgery is the only potentially curative treatment for advanced, resectable gastric cancer, but locoregional relapse rate is high with a consequently poor prognosis. To improve survival, several preoperative and postoperative treatment strategies have been investigated. Whereas perioperative chemotherapy and postoperative chemoradiation (CRT) are considered standard therapy in the Western world, in Asia postoperative monochemotherapy with S-1 is often used. Several other therapeutic options, although generally not accepted as standard treatment, are postoperative combination chemotherapy, hyperthermic intraperitoneal chemotherapy and preoperative radiotherapy and CRT. Postoperative combination chemotherapy does show a statistically significant but clinically equivocal survival advantage in several meta-analyses. Hyperthermic intraperitoneal chemotherapy is mainly performed in Asia and is associated with a higher postoperative complication rate. Based on the currently available data, the use of postoperative radiotherapy alone and the use of intraoperative radiotherapy should not be advised in the treatment of resectable gastric cancer. Western randomized trials on gastric cancer are often hampered by slow or incomplete accrual. Reduction of toxicity for preoperative and especially postoperative treatment is essential for the ongoing improvement of gastric cancer care.

Neo-adjuvant chemotherapy followed by surgery and chemotherapy or by surgery and chemoradiotherapy for patients with resectable gastric cancer (CRITICS)

BACKGROUND

Radical surgery is the cornerstone in the treatment of resectable gastric cancer. The Intergroup 0116 and MAGIC trials have shown benefit of postoperative chemoradiation and perioperative chemotherapy, respectively. Since these trials cannot be compared directly, both regimens are evaluated prospectively in the CRITICS trial. This study aims to obtain an improved overall survival for patients treated with preoperative chemotherapy and surgery by incorporating radiotherapy concurrently with chemotherapy postoperatively.

METHODS/DESIGN

In this phase III multicentre study, patients with resectable gastric cancer are treated with three cycles of preoperative ECC (epirubicin, cisplatin and capecitabine), followed by surgery with adequate lymph node dissection, and then either another three cycles of ECC or concurrent chemoradiation (45 Gy, cisplatin and capecitabine). Surgical, pathological, and radiotherapeutic quality control is performed. The primary endpoint is overall survival, secondary endpoints are disease-free survival (DFS), toxicity, health-related quality of life (HRQL), prediction of response, and recurrence risk assessed by genomic and expression profiling. Accrual for the CRITICS trial is from the Netherlands, Sweden, and Denmark, and more countries are invited to participate.

CONCLUSION

Results of this study will demonstrate whether the combination of preoperative chemotherapy and postoperative chemoradiotherapy will improve the clinical outcome of the current European standard of perioperative chemotherapy, and will therefore play a key role in the future management of patients with resectable gastric cancer.

TRIAL REGISTRATION

clinicaltrials.gov NCT00407186.

Neo-adjuvant chemotherapy followed by surgery and chemotherapy or by surgery and chemoradiotherapy for patients with resectable gastric cancer (CRITICS)

Background

Radical surgery is the cornerstone in the treatment of resectable gastric cancer. The Intergroup 0116 and MAGIC trials have shown benefit of postoperative chemoradiation and perioperative chemotherapy, respectively. Since these trials cannot be compared directly, both regimens are evaluated prospectively in the CRITICS trial. This study aims to obtain an improved overall survival for patients treated with preoperative chemotherapy and surgery by incorporating radiotherapy concurrently with chemotherapy postoperatively.

Methods/design

In this phase III multicentre study, patients with resectable gastric cancer are treated with three cycles of preoperative ECC (epirubicin, cisplatin and capecitabine), followed by surgery with adequate lymph node dissection, and then either another three cycles of ECC or concurrent chemoradiation (45 Gy, cisplatin and capecitabine). Surgical, pathological, and radiotherapeutic quality control is performed. The primary endpoint is overall survival, secondary endpoints are disease-free survival (DFS), toxicity, health-related quality of life (HRQL), prediction of response, and recurrence risk assessed by genomic and expression profiling. Accrual for the CRITICS trial is from the Netherlands, Sweden, and Denmark, and more countries are invited to participate.

Conclusion

Results of this study will demonstrate whether the combination of preoperative chemotherapy and postoperative chemoradiotherapy will improve the clinical outcome of the current European standard of perioperative chemotherapy, and will therefore play a key role in the future management of patients with resectable gastric cancer.

Trial registration

clinicaltrials.gov NCT00407186

Adjuvant chemoradiation for resected gastric cancer: a 10-year experience

BACKGROUND

The Intergroup 0116 study demonstrated that concurrent chemoradiation improved overall survival (OS) in resected gastric cancer. However, there are few reports focusing on late toxicity and factors governing prognosis. This study aimed to determine these two important aspects for employing this regimen.

METHODS

Patients with resected gastric cancer stage IB to IV (M0) disease, treated between July 1998 and December 2007, were analyzed. The majority of the patients were treated using 5 cycles of 5-fluorouracil (5FU)/leucovorin chemotherapy with 45 Gy/25 fractions radiotherapy concurrent with cycles 2 and 3, as per the Intergroup 0116 study.

RESULTS

We treated 120 patients (107 standard protocol, 13 with concurrent 5FU alone), and 14% had a close or positive margin. Median age was 59 years (35-79 years). Acute toxicity ≥ grade 3 was seen in 66% of all patients (hematological 61%, stomatitis 3%, diarrhea 6%, vomiting 2%). Median follow-up was 33 months (range 6-125 months). Five-year OS and relapse-free survival were 51 and 54%, respectively. On multivariate analysis, surgical margin status, stage of the disease, and radiotherapy with computed tomography (CT) planning were important prognostic factors. Anemia and gastritis were the two most frequently occurring late complications, though they were usually mild and asymptomatic. Clinically significant renal impairment was uncommon. Other rare complications included intestinal obstruction, malabsorption, hypertension, and secondary malignancy.

CONCLUSIONS

Postoperative chemoradiation is safe and late toxicity is usually mild in extent. Results were comparable to the Intergroup 0116 study. R0 resection is of utmost importance and radiotherapy should best be delivered by conformal techniques.