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

Generation of a competing endogenous RNA network and validation of BNIP1 expression in the lung of irradiated mice

BACKGROUND

Radiation-induced lung injury (RILI) is a serious complication of radiation therapy, and it is mediated by long non-coding RNAs (lncRNAs).

STUDY DESIGN AND METHODS

Mouse lung tissues were examined using RNA-Seq and RNA-Seq libraries 72 h after the administration of 6 Gy of X-ray irradiation. The target mRNAs were functionally annotated and the target lncRNA-based miRNAs and target miRNA-based mRNAs were predicted after irradiation to establish the lncRNA-miRNA-mRNA ceRNA axis.

RESULTS

The analyses showed that relative to unirradiated controls, 323 mRNAs, 114 miRNAs, and 472 lncRNAs were significantly up-regulated following irradiation, whereas 1907 mRNAs, 77 miRNAs, and 1572 lncRNAs were significantly down-regulated following irradiation. Voltage-gated ion channels, trans-membrane receptor protein tyrosine kinases, and vascular endothelial growth factor have all been associated with dysregulated miRNA-mRNA relationships. KEGG pathway analysis of the dysregulated miRNA-mRNA targets revealed involvement in pathways associated with the hedgehog signaling pathway-fly, ErbB signaling, VEGF signaling, axon guidance, and focal adhesion. KEGG analysis of differentially expressed showed enrichment of mRNAs in primary immunodeficiency, the intestinal immune axis for IgA production, hematopoietic cell lineages, systemic lupus erythematosus, and Th1 and Th2 cell differentiation. Finally, the ceRNA network revealed that BNIP1 was a critical mRNA modulated by the most significant upregulation of lncRNA E230013L22Rik.

CONCLUSION

In summary, the lncRNA-miRNA-mRNA ceRNA axis of RILI was constructed following irradiation in a mouse model. RNA dysregulation in the early stage of RILI may lead to severe complications at a later stage, with BNIP1 contributing to radiation-induced cellular apoptosis in RILI.

Mast1 mediates radiation-induced gastric injury via the P38 MAPK pathway

Radiation-induced gastric injury is a serious adverse effect and reduces the efficacy of radiotherapy treatment. However, the mechanisms underlying radiation-induced stomach injury remain unclear. Here, mouse stomach and gastric epithelial cells were irradiated with different doses of X-ray radiation. The results showed that radiation induced gastric injury in vivo and in vitro. Differentially expressed functional mRNAs in irradiation-induced gastric tissues were screened from the Gene Expression Omnibus (GEO) database. We found that the expression of microtubule-associated serine/threonine kinase 1 (Mast1) was downregulated in mouse gastric tissues and gastric epithelial cells after irradiation. Furthermore, functional assays showed that knockdown of Mast1 inhibited growth and promoted apoptosis in gastric epithelial cells, while overexpression of Mast1 protected gastric epithelial cells from radiation damage. Mechanistically, Mast1 negatively regulated radiation-induced injury in gastric epithelial cells by inhibiting the activation of P38. The apoptosis caused by knockdown of Mast1 in gastric epithelial cells could be partially reversed by the P38 inhibitor SB203580. Moreover, data from several gastric cancer cell lines and online databases revealed that Mast1 was not involved in the development of gastric cancer. Collectively, our findings demonstrated that Mast1 is essential for radiation-induced gastric injury, providing a promising prognostic and therapeutic target.

Cone Beam CT-Based Daily Adaptive Planning or Defined-Filling Protocol for Neoadjuvant Gastric Cancer Radiation Therapy: A Comparison

Purpose

This study aimed to investigate, in the setting of neoadjuvant gastric irradiation with integrated boost, whether cone beam computed tomography (CBCT)-based adaptive radiation therapy compared with a defined-filling protocol would be beneficial in terms of feasibility and achieving daily reproducible dose volume indexes of the planning target volume (PTV) and organs at risk (OARs) and workflow.

Methods and materials

Planning computed tomography (PCT) and 25 CBCT scans of a previously treated patient were used, and neoadjuvant therapy of gastric carcinoma was simulated offline. PTVs and OARs were defined per the TOPGEAR protocol (PTV: 45 Gy/1.8 Gy), and an integrated boost (gross tumor volume [GTV]: 50.4 Gy/2.016 Gy) was added. The patient followed a filling regimen consisting of 12-hour fasting followed by 200 mL of water intake (2 glasses of water) immediately before irradiation. OARs and PTVs were newly contoured on each CBCT. Nonrigid registration of PCT and CBCT scans was performed. Nonadapted plans were recalculated on each CBCT (R-CBCT). Furthermore, an adapted plan was created for the new anatomy (A-CBCT). Dose parameters and comparison of R-CBCT and A-CBCT for the kidneys, liver, and heart were analyzed using a paired t test.

Results

A total of 200 plans for R-CBCT and A-CBCT were obtained. Mean gastric volumes were 277.32 cm³ (±54.40 cm³) in CBCT scans and 519.2 cm³ in PCT. Mean doses to the PTV did not differ meaningfully within the CBCT scans, with an average of 1.54%. The D₉₅ improved in GTV coverage by 5.26% compared with the R-CBCT plan. Mean heart, liver, and right kidney doses were reduced with the A-CBCT plan by 35.74%, 10.71% and 29.47%, respectively. The R- and A-CBCT comparison for GTV and OARs was significantly different in all cases (P < .0001).

Conclusions

Adaptive radiation therapy through deformable registration represents an important tool in neoadjuvant gastric irradiation, encompassing daily variability and organ motion, compared with the defined-filling protocol while improving OAR sparing.

mRNA and lncRNA Expression Profiling of Radiation-Induced Gastric Injury Reveals Potential Radiation-Responsive Transcription Factors

Radiation-induced gastric injury is a serious concern that may limit the duration and the delivered dose of radiation. However, the genome-wide molecular changes in stomach upon ionizing radiation have not been reported. In this study, mouse stomach was irradiated with 6 or 12 Gy X-ray irradiation and we found that radiation resulted in the atrophy of gastric mucosa and abnormal morphology of chief and parietal cells. Radiation-induced gastric injury was accompanied by an increase in the serum levels of pepsinogen A and pepsinogen C but not gastrin-17. The expression profiles of messenger RNA (mRNA) and long noncoding RNA (lncRNA) in normal and irradiated gastric tissues were measured by microarray analysis. Results revealed 17 upregulated and 10 downregulated mRNAs were consistent in 6 and 12 Gy irradiated gastric tissues, including D site-binding protein (Dbp) and fibrinogen-like protein 1 (Fgl1). Thirteen upregulated and 96 downregulated lncRNAs were commonly changed in 6 and 12 Gy irradiated gastric tissues. The dysregulated mRNAs were implicated in multiple pathways and showed coexpression with lncRNAs. To identify motifs for transcription factors and coactivators in the proximal promoter regions of the dysregulated RNAs, the bioinformatic tool Biopython was used. A variety of common motifs that are associated with transcription factors were identified, including ZNF263, LMX1B, and Dlx1. Our findings illustrate the molecular changes during radiation-induced gastric injury and the potential transcription factors driving this alteration.

Automated VMAT planning for postoperative adjuvant treatment of advanced gastric cancer

Background

Postoperative/adjuvant radiotherapy of advanced gastric cancer involves a large planning target volume (PTV) with multi-concave shapes which presents a challenge for volumetric modulated arc therapy (VMAT) planning. This study investigates the advantages of automated VMAT planning for this site compared to manual VMAT planning by expert planners.

Methods

For 20 gastric cancer patients in the postoperative/adjuvant setting, dual-arc VMAT plans were generated using fully automated multi-criterial treatment planning (autoVMAT), and compared to manually generated VMAT plans (manVMAT). Both automated and manual plans were created to deliver a median dose of 45 Gy to the PTV using identical planning and segmentation parameters. Plans were evaluated by two expert radiation oncologists for clinical acceptability. AutoVMAT and manVMAT plans were also compared based on dose-volume histogram (DVH) and predicted normal tissue complication probability (NTCP) analysis.

Results

Both manVMAT and autoVMAT plans were considered clinically acceptable. Target coverage was similar (manVMAT: 96.6 ± 1.6%, autoVMAT: 97.4 ± 1.0%, p = 0.085). With autoVMAT, median kidney dose was reduced on average by > 25%; (for left kidney from 11.3 ± 2.1 Gy to 8.9 ± 3.5 Gy (p = 0.002); for right kidney from 9.2 ± 2.2 Gy to 6.1 ± 1.3 Gy (p <  0.001)). Median dose to the liver was lower as well (18.8 ± 2.3 Gy vs. 17.1 ± 3.6 Gy, p = 0.048). In addition, Dmax of the spinal cord was significantly reduced (38.3 ± 3.7 Gy vs. 31.6 ± 2.6 Gy, p <  0.001). Substantial improvements in dose conformity and integral dose were achieved with autoVMAT plans (4.2% and 9.1%, respectively; p <  0.001). Due to the better OAR sparing in the autoVMAT plans compared to manVMAT plans, the predicted NTCPs for the left and right kidney and the liver-PTV were significantly reduced by 11.3%, 12.8%, 7%, respectively (p ≤ 0.001). Delivery time and total number of monitor units were increased in autoVMAT plans (from 168 ± 19 s to 207 ± 26 s, p = 0.006) and (from 781 ± 168 MU to 1001 ± 134 MU, p = 0.003), respectively.

Conclusions

For postoperative/adjuvant radiotherapy of advanced gastric cancer, involving a complex target shape, automated VMAT planning is feasible and can substantially reduce the dose to the kidneys and the liver, without compromising the target dose delivery.

Electronic supplementary material

The online version of this article (10.1186/s13014-018-1032-z) contains supplementary material, which is available to authorized users.

The effect of dose escalation on gastric toxicity when treating lower oesophageal tumours: a radiobiological investigation

PURPOSE

Using radiobiological modelling to estimate normal tissue toxicity, this study investigates the effects of dose escalation for concurrent chemoradiation therapy (CRT) in lower third oesophageal tumours on the stomach.

METHODS AND MATERIALS

10 patients with lower third oesophageal cancer were selected from the SCOPE 1 database (ISCRT47718479) with a mean planning target volume (PTV) of 348 cm(3). The original 3D conformal plans (50 Gy3D) were compared to newly created RapidArc plans of 50 GyRA and 60 GyRA, the latter using a simultaneous integrated boost (SIB) technique using a boost volume, PTV2. Dose-volume metrics and estimates of normal tissue complication probability (NTCP) were compared.

RESULTS

There was a significant increase in NTCP of the stomach wall when moving from the 50 GyRA to the 60 GyRA plans (11-17 %, Wilcoxon signed rank test, p = 0.01). There was a strong correlation between the NTCP values of the stomach wall and the volume of the stomach wall/PTV 1 and stomach wall/PTV2 overlap structures (R = 0.80 and R = 0.82 respectively) for the 60 GyRA plans.

CONCLUSION

Radiobiological modelling suggests that increasing the prescribed dose to 60 Gy may be associated with a significantly increased risk of toxicity to the stomach. It is recommended that stomach toxicity be closely monitored when treating patients with lower third oesophageal tumours with 60 Gy.

Efficacy of palliative radiotherapy for gastric bleeding in patients with unresectable advanced gastric cancer: a retrospective cohort study

Background

Bleeding negatively impacts quality of life in patients with unresectable advanced gastric cancer and has the potential to be lethal. When blood transfusion and endoscopic hemostasis are unsuccessful to stop bleeding, radiation to stomach is selected in patients with unsuitable condition for surgery. We performed a retrospective cohort study to clarify the utility of radiotherapy in treating gastric bleeding, particularly for patients with limited life expectancy.

Methods

We evaluated the efficacy and safety of palliative radiotherapy in patients with advanced gastric cancer between January 2007 and December 2012 in Aichi Cancer Center Hospital. All patients had gastric bleeding requiring blood transfusion. We defined hemostasis as an increase in hemoglobin level to more than 7.0 g/dL together with the cessation of melena or hematemesis for at least 1 week.

Results

During the study period, 313 advanced gastric cancer patients treated in our institution. Of these 17 patients received gastric radiotherapy to stop bleeding. Two patients were excluded from analysis due to combined treatment of intravascular embolization. Eleven out of 15 patients (73 %) had undergone two or more previous chemotherapy regimens. Ten patients (67 %) had an Eastern Cooperative Oncology Group performance status of 3 and 14 patients (93 %) were in palliative prognostic index group B or C. The median total planned radiation dose was 30 Gy in 10 fractions. At a median interval of 2 days after initiation of radiotherapy, 11 patients (73 %) achieved hemostasis; rebleeding was observed in four patients (36 %). The median hemoglobin level before radiotherapy was significantly increased from 6.0 to 9.0 g/dL (p < 0.0001). The median volume of red blood cell transfusion was significantly decreased from 1120 to 280 mL (p = 0.007). The median rebleeding-free survival interval was 27 days, with a median overall survival of 63 days. The cause of death was bleeding in 1 patient (7 %) and cancer progression without bleeding in 12 patients (80 %). There were no severe adverse events attributable to radiotherapy.

Conclusions

Palliative radiotherapy for gastric bleeding achieves hemostasis within a short time frame. This appears to be a useful treatment option, especially for patients with end-stage, unresectable advanced gastric cancer.

Concurrent Neoadjuvant Chemoradiotherapy for Siewert II and III Adenocarcinoma at Gastroesophageal Junction

OBJECTIVE

This study was conducted to investigate the efficacy and safety of using a concurrent neoadjuvant chemoradiotherapy (a XELOX regimen) to treat adenocarcinoma of the gastroesophageal junction.

METHODS

Seventy-six patients having resectable adenocarcinoma at the gastroesophageal junction (T3/4, N+, M0) were recruited to participate and randomly assigned to either a chemoradiotherapy group or a surgery group. Patients in the chemoradiotherapy group were orally given capecitabine (1,000 mg/m2, twice daily for 14 days, days 1-14) and intravenous oxaliplatin (130 mg/m2 on day 1) for 2 cycles. Radiotherapy was performed with a total of 45 Gy administered in 25 sessions for 5 weeks. Patients in the surgery group received only surgical intervention.

RESULTS

In the concurrent chemoradiotherapy group, the overall response rate was 55.6% (20/36), tumor control rate was 100% and a pathological complete response was achieved in 16.7% (6/36). The entire chemoradiotherapy group had R0 resections as did 80% of the surgery group (32/40) (P < 0.05). In the concurrent chemoradiotherapy group, 6 patients developed grade 3 side effects. Treatment was either discontinued or the dose adjusted. Major hematological side effects in the chemoradiotherapy group included leukopenia, neutropenia, anemia and thrombocytopenia. Nonhematological side effects included nausea, vomiting and appetite loss. Chemoradiotherapy-related death was not observed.

CONCLUSIONS

Concurrent neoadjuvant chemoradiotherapy administration increased the rate of R0 resection and demonstrated favorable safety in patients with Siewert II or III adenocarcinoma at the gastroesophageal junction. These results support the use of neoadjunctive chemoradiotherapy in the treatment of adenocarcinoma of the gastroesophageal junction.

Preoperative treatment with radiochemotherapy for locally advanced gastroesophageal junction cancer and unresectable locally advanced gastric cancer

Background.

To purpose of the study was to analyze the results of preoperative radiochemotherapy in patients with unresectable gastric or locoregionally advanced gastroesophageal junction (GEJ) cancer treated at a single institution.

Patients and methods.

Between 1/2004 and 6/2012, 90 patients with locoregionally advanced GEJ or unresectable gastric cancer were treated with preoperative radiochemotherapy at the Institute of Oncology Ljubljana. Planned treatment schedule consisted of induction chemotherapy with 5-fluorouracil and cisplatin, followed by concomitant radiochemotherapy four weeks later. Three-dimensional conformal external beam radiotherapy was delivered by dual energy (6 and 15 MV) linear accelerator in 25 daily fractions of 1.8 Gy in 5 weeks with two additional cycles of chemotherapy repeated every 28 days. Surgery was performed 4–6 weeks after completing radiochemotherapy. Following the surgery, multidisciplinary advisory team reassessed patients for the need of adjuvant chemotherapy. The primary endpoints were histopathological R0 resection rate and pathological response rate. The secondary endpoints were toxicity of preoperative radiochemotherapy and survival.

Results.

Treatment with preoperative radiochemotherapy was completed according to the protocol in 84 of 90 patients (93.3%). Twenty patients (22.2%) did not undergo the surgery because of the disease progression, serious comorbidity, poor performance status or still unresectable tumour. In 13 patients (14.4%) only exploration was performed because the tumour was assessed as unresectable or diffuse peritoneal carcinomatosis was established. Fifty-seven patients (63.4%) underwent surgery with the aim of complete removal of the tumour. Radical resection was achieved in 50 (55.6%) patients and the remaining seven (7.8%) patients underwent non-radical surgery (R1 in five and R2 in two patients). In this group of patients (n = 57), pathological complete response of tumour was achieved in five patients (5.6% of all treated patients or 8.8% of all operated patients). Down-staging was recorded in 49 patients (86%), in one patient (1.8%) the stage after radiochemotherapy was unchanged while in seven patients (12.3%) the pathological stage was higher than clinical, mainly due to higher pN stage. No death was recorded during preoperative radiochemotherapy. Most grade 3 and 4 toxicities were due to vomiting, nausea and bone marrow suppression (granulocytopenia). Twenty-six (45.6%) patients died due to GEJ or gastric carcinoma, one died because of septic shock following the surgery and a reason for two deaths was unknown. Twenty-eight patients (49.1%) were disease free at the time of analysis, while 29 patients (50.9%) developed the recurrence, mostly as distant metastases. At two years, locoregional control, disease-free survival, disease-specific survival and overall survival were 82.9%, 43.9%, 56.9% and 53.9%, respectively.

Conclusions.

Preoperative radiochemotherapy was feasible in our group of patients and had acceptable toxicity. Majority of patients achieved down-staging, allowing greater proportion of radical resections (R0), which are essential for patients’ cure.

Neoadjuvant chemoradiotherapy in non-cardia gastric cancer patients--does it improve survival?

BACKGROUND

Survival rates after resection of advanced gastric cancer are extremely poor. An increasing number of patients with gastric carcinomas (GC) are therefore being treated with preoperative chemotherapy. We evaluated 36 month survival rate of GC patients that were treated by adding a neoadjuvant chemoradiotherapy before gastrostomy.

MATERIALS AND METHODS

Patients with stage II or III gastric adenocarcinomas were enrolled. The patients divided into two groups: (A) Neoadjuvant group that received concurrent chemoradiation before surgery (4,500 cGy of radiation at 180 cGy per day plus chemotherapy with cisplatin and 5-fluorouracil, in the first and the end four days of radiotherapy). Resection was attempted 5 to 6 weeks after end of chemoradiotherapy. (B) Adjuvant group that received concurrent chemo-radiation after surgical resection.

RESULTS

Two (16.7%) patients out of 12 patients treated with neoadjuvant chemo-radiotherapy and 5 (38.5%) out of 13 in the surgery group survived after 36 months. These rates were not significantly different with per protocol and intention-to-treat analysis. The median survival time of patients in group A and B were 13.4 and 21.6 months , respectively, again not significantly different. Survival was significantly greater in patients with well differentiated adenocarcinoma in group B than in group A (p<0.004).

CONCLUSIONS

According to this study we suggest surgery then chemoradiotherapy for patients with well differentiated gastric adenocarcinoma rather than other approaches. Additional studies with greater sample size and accurate matching relying on cancer molecular behavior are recommended.

Modulation of microRNAs by ionizing radiation in human gastric cancer

Gastric cancer is one of the most common cancers in China. Although surgery is the primary therapeutic method, radiotherapy has become an integral part, particularly in the early and intermediate stages of gastric cancer. microRNAs (miRNAs) are involved in the regulation of diverse cellular processes in response to intrinsic and extrinsic stress. A change in miRNA expression profile has been identified in various types of tumor cells in response to radiation; however, there is no relevant information concerning gastric cancer. In the present study, we investigated the miRNA profiles of two clinical gastric cancer samples exposed to X‑rays using miRNA microarray. We found that 16 miRNAs were downregulated and 2 miRNAs were upregulated significantly in both irradiated samples when compared with the unirradiated samples. Decreases in the levels of miR‑300 and miR‑642 expression were confirmed by qRT‑PCR in more clinical samples and in cultured cell lines. We predicted the targets of the two miRNAs with TargetScan and classified all the candidate targets with Gene Ontology, which indicated that both miR‑300 and miR‑642 potentially regulate cellular radiation response by modulating apoptosis, cell cycle regulation and DNA damage and repair pathway-related genes. Cell cycle assay and immunofluorescence assay demonstrated that miR‑300 regulates radiation‑induced G2 cell cycle arrest and DNA damage repair. In conclusion, our findings indicate that ionizing radiation modulates the miRNA expression profile, and the changes in several specific miRNAs such as miR‑300 have the potential to be used in the treatment, diagnosis and prognosis of gastric cancer.

Capecitabine in adjuvant radiochemotherapy for gastric adenocarcinoma

BACKGROUND

In patients with non-metastatic gastric cancer surgery still remains the treatment of choice. Postoperative radiochemotherapy with 5-fluorouracil and leucovorin significantly improves the treatment outcome. The oral fluoropyrimidines, such as capecitabine, mimic continuous 5-fluorouracil infusion, are at least as effective as 5-fluorouracil, and such treatment is more comfortable for the patients.

PATIENTS AND METHODS

In the period from October 2006 to December 2009, 101 patients with gastric cancer in stages Ib-IIIc were treated with postoperative chemoradiation with capecitabine. Distal subtotal resection of the stomach was performed in 46.3%, total resection in 50.5% and multivisceral resection in 3.2% of patients. The main endpoints of this study were loco-regional control (LRC), disease-free survival (DFS), disease-specific survival (DSS) and overall survival (OS). The rates of acute side-effects were also estimated.

RESULTS

Seventy-seven percent of patients completed the treatment according to the protocol. The median follow-up time of all patients was 3.9 years (range: 0.4-6.3 years) and in survivors it was 4.7 years (range: 3.2-6.3 years). No death occurred due to the therapy. Acute toxicity, such as nausea and vomiting, stomatitis, diarrhoea, hand-foot syndrome and infections of grade 3 or 4, occurred in 5%, 1%, 2%, 8.9% and 18.8% of patients, respectively. On the close-out date 63.4% patients were still alive and with no signs of the disease. The 4-years follow-up survey showed that LRC, DFS, DSS and OS were 95.5%, 69.2%, 70.7%, and 66.2%, respectively. Higher pN-stage and splenectomy were found to be independent prognostic factors for all four types of survival and perineural invasion and lower treatment intensity for DFS, DSS and OS.

CONCLUSIONS

Postoperative radiochemotherapy with capecitabine is feasible, with low toxicity and the results of such treatment are good.

Role of stenting in the palliation of gastroesophageal junction cancer: A brief review

Gastroesophageal junction cancer has an increasing incidence in western countries. It is inoperable when first manifested in more than 50% of cases. So, palliation is the only therapeutic option for the advanced disease to relieve dysphagia and its consequences in weakened patients with an estimated mean survival under 6 mo. This article has tried to identify trends focusing on current information about the best palliative treatment, with an emphasis on the role of stenting. Self-expanding stent placement, either metal or plastic, is the main management option. However, this anatomical location creates some particular problems for stent safety and effectiveness which may be overcome by properly designed novel stents. The stents ensure a good quality of life and must be preferred over other alternative methods of loco-regional modalities, i.e., external radiation, laser thermal or photodynamic therapy. Although stent placement is generally a simple, safe and effective method, there are sometimes complications, increasing the morbidity and mortality rate. Bypass operative procedures have now been abandoned as a first choice. The stomach instead of the colon must be used for a bypass operation when it is needed. Chemotherapy, despite the toxicity, and intraluminal radiation (brachytherapy) have a well-defined role.

Long-term prognostic value of mesorectal grading after neoadjuvant chemoradiotherapy for rectal cancer

BACKGROUND

Mesorectal grading was reported to be a valuable prognostic factor in rectal cancer surgery. Previous studies were retrospective, and had short follow-up.

OBJECTIVE

To assess the long-term influence of total mesorectal excision quality on disease recurrence in mid and low rectal cancer patients who received preoperative neoadjuvant chemoradiotherapy (CRT) and postoperative chemotherapy.

METHODS

One hundred twenty-one patients with rectal cancer had either low anterior resection or abdominoperineal resection. All patients received neoadjuvant CRT and postoperative chemotherapy. Main outcome measures included TNM staging, involvement of the circumferential resection margin (ICRM), mesorectal grading, local and systemic recurrences were recorded.

RESULTS

Follow-up was done for at least 5 years or up to disease recurrence whatever comes first. Mean follow-up time was 59.4 months. Twenty-nine patients had abdominoperineal resection and 92 had low anterior resection. About 7.5% had positive CRM which was significantly correlated with mesorectal grading. Grade 3 mesorectal specimens were obtained in approximately 60% of patients, 27% had grade 2, and only 13% had grade 1 (poor) mesorectal specimens. Poorer mesorectal grading increased with APR and lower rectal tumors. Recurrences occurred in 20% of patients (40% in the first 2 years, 32% in the 3rd year, and 28% in the 4th and 5th years); factors affecting recurrence included lymphovascular invasion, ICRM, and N stage. Mesorectal grading was not a valuable prognostic factor for recurrence unless it resulted in ICRM. Recurrences occurred earlier with poorer mesorectal grade, yet this was not statistically significant.

CONCLUSIONS

Mesorectal grading is a pathologic description that reflects the quality of surgery. However, in patients who received neoadjuvant CRT and postoperative chemotherapy, grading had no long-term prognostic value regarding recurrences unless it resulted in ICRM.

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.