Intensive preoperative radiotherapy with local hyperthermia for the treatment of gastric carcinoma

Poorly cohesive cells gastric carcinoma including signet-ring cell cancer: Updated review of definition, classification and therapeutic management

While the incidence of gastric cancer (GC) in general has decreased worldwide in recent decades, the incidence of diffuse cancer historically comprising poorly cohesive cells-GC (PCC-GC) and including signet ring cell cancer is rising. Literature concerning PCC-GC is scarce and unclear, mostly due to a large variety of historically used definitions and classifications. Compared to other histological subtypes of GC, PCC-GC is nevertheless characterized by a distinct set of epidemiological, histological and clinical features which require a specific diagnostic and therapeutic approach. The aim of this review was to provide an update on the definition, classification and therapeutic strategies of PCC-GC. We focus on the updated histological definition of PCC-GC, along with its implications on future treatment strategies and study design. Also, specific considerations in the diagnostic management are discussed. Finally, the impact of some recent developments in the therapeutic management of GC in general such as the recently validated taxane-based regimens (5-Fluorouracil, leucovorin, oxaliplatin and docetaxel), the use of hyperthermic intraperitoneal chemotherapy as well as pressurized intraperitoneal aerosol chemotherapy and targeted therapy have been reviewed in depth for their relative importance for PCC-GC in particular.

Current and future strategies for radiation therapy in gastric cancer

Gastric cancers are heterogeneous. There are important differences between gastric and junctional tumors and a focus on evidence based on true gastric cancers is important to guide treatment decision and the design of innovative strategies. We present key evidence shaping the current use of radiotherapy, discuss technical radiotherapy considerations that are important to consider in multidisciplinary decision-making, and highlight selected research strategies including radiotherapeutic advances, theranostic approaches and key ongoing clinical trials to watch that will shape the role of radiotherapy in gastric cancers for the future.

Quo Vadis Oncological Hyperthermia (2020)?

Heating as a medical intervention in cancer treatment is an ancient approach, but effective deep heating techniques are lacking in modern practice. The use of electromagnetic interactions has enabled the development of more reliable local-regional hyperthermia (LRHT) techniques whole-body hyperthermia (WBH) techniques. Contrary to the relatively simple physical-physiological concepts behind hyperthermia, its development was not steady, and it has gone through periods of failures and renewals with mixed views on the benefits of heating seen in the medical community over the decades. In this review we study in detail the various techniques currently available and describe challenges and trends of oncological hyperthermia from a new perspective. Our aim is to describe what we believe to be a new and effective approach to oncologic hyperthermia, and a change in the paradigm of dosing. Physiological limits restrict the application of WBH which has moved toward the mild temperature range, targeting immune support. LRHT does not have a temperature limit in the tumor (which can be burned out in extreme conditions) but a trend has started toward milder temperatures with immune-oriented goals, developing toward immune modulation, and especially toward tumor-specific immune reactions by which LRHT seeks to target the malignancy systemically. The emerging research of bystander and abscopal effects, in both laboratory investigations and clinical applications, has been intensified. Our present review summarizes the methods and results, and discusses the trends of hyperthermia in oncology.

Neoadjuvant therapy strategies for advanced gastric cancer: Current innovations and future challenges

Gastric cancer, which has a high incidence and poor prognosis, remains a therapeutic challenge. Recently, neoadjuvant therapy has attracted increasing attention due to high recurrence rate and low survival rate after resection in most patients with advanced stage. Clinical trials show that neoadjuvant approaches confer a significant survival advantage for resectable locally advanced gastric cancer. The specific advantages of chemoradiotherapy compared with chemotherapy have not been clarified; optimal regimens and cycles, particularly in the preoperative setting, should be studied further; and trials aimed at determining the role of targeted and immunological therapies should be conducted.

Prognostic effect of adjuvant chemoradiotherapy for patients with gastric cancer: an updated evidence of randomized controlled trials

The prognostic effect of chemoradiotherapy in gastric cancer has been evaluated for decades while the results are still in debate and heterogeneous. We thus comprehensively updated the evidence through systematic review and meta-analysis to evaluate chemoradiotherapy in gastric cancer to determine its effect. Pubmed, EMBASE, and Cochrane Library from the earliest possible year to April 2017 were searched. Randomised controlled trials (RCTs) that assessed the effects of combined chemoradiotherapy for patients with gastric cancer compared with that of single chemotherapy were included. The main outcome measure was 5-year overall survival (OS) and the second was disease-free survival (DFS) or recurrence-free survival (RFS). Fifteen RCTs involving 3347 patients were included into this meta-analysis. Compared with single chemotherapy, the relative risk (RR) for 5-year OS for chemoradiotherapy was 1.05 (95% CI 0.88 to 1.25), with moderate heterogeneity across eligible trials (I² = 55.7%, p = 0.016). Subgroup analyses and sensitivity analyses confirmed the consistent findings. We found that significant survival benefit for 5-year DFS/RFS for chemoradiotherapy over single chemotherapy (RR 0.89 95% CI 0.81 to 0.98) for patients with gastric cancer. This updated meta-analysis does not provide strong evidence for a 5-year survival benefit of chemoradiotherapy over chemotherapy alone in patients with gastric cancer. A clear advantage of chemoradiotherapy over chemotherapy has not been established. Further larger RCTs should be conducted to determine its true effect.

The Impact of Positive Margins on Outcome Among Patients With Gastric Cancer Treated With Radiation

OBJECTIVES

Positive surgical margins have been associated with worse outcomes in gastric cancer patients. We evaluated the impact of positive margins in a modern cohort treated with radiotherapy.

METHODS

We performed a multi-institutional retrospective analysis of patients treated from 1998 through 2010. All underwent definitive surgery and were followed up for recurrence and survival. We assessed associations with positive margins using the log-rank tests and Cox proportional hazard models.

RESULTS

We identified 91 patients with a median follow-up of 42 months. Seven received radiation before surgery; the remainder were treated postoperatively. Epirubicin-based chemotherapy was given to 8 patients perioperatively and 25 postoperatively. Nineteen had positive margins (21%), including 25% of patients who received chemotherapy perioperatively. All patients who received neoadjuvant radiotherapy had negative margins. There were 41 recurrences and 44 deaths. Positive margins were associated with increased recurrence risk after adjusting for other factors (hazard ratio=2.8, P=0.01). In addition, median survival with positive margins was 31 months as compared with 77 months after complete resection (P=0.13).

CONCLUSIONS

Positive margins were associated with recurrence despite aggressive multimodality therapy including radiotherapy and the selective use of chemotherapy. Thus, additional consideration is warranted for strategies such as neoadjuvant chemoradiation intended to facilitate complete resection.

Rationale of hyperthermia for radio(chemo)therapy and immune responses in patients with bladder cancer: Biological concepts, clinical data, interdisciplinary treatment decisions and biological tumour imaging

Bladder cancer, the most common tumour of the urinary tract, ranks fifth among all tumour entities. While local treatment or intravesical instillation of bacillus Calmette-Guerin (BCG) provides a treatment option for non-muscle invasive bladder cancer of low grade, surgery or radio(chemo)therapy (RT) are frequently applied in high grade tumours. It remains a matter of debate whether surgery or RT is superior with respect to clinical outcome and quality of life. Surgical resection of bladder cancer can be limited by acute side effects, whereas, RT, which offers a non-invasive treatment option with organ- and functional conservation, can cause long-term side effects. Bladder toxicity by RT mainly depends on the total irradiation dose, fraction size and tumour volume. Therefore, novel approaches are needed to improve clinical outcome. Local tumour hyperthermia is currently used either as an ablation therapy or in combination with RT to enhance anti-tumour effects. In combination with RT an increase of the temperature in the bladder stimulates the local blood flow and as a result can improve the oxygenation state of the tumour, which in turn enhances radiation-induced DNA damage and drug toxicity. Hyperthermia at high temperatures can also directly kill cells, particularly in tumour areas which are poorly perfused, hypoxic or have a low tissue pH. This review summarises current knowledge relating to the role of hyperthermia in RT to treat bladder cancer, the induction and manifestation of immunological responses induced by hyperthermia, and the utilisation of the stress proteins as tumour-specific targets for tumour detection and monitoring of therapeutic outcome.

Neo-adjuvant chemo(radio)therapy in gastric cancer: Current status and future perspectives

In the last 20 years, several clinical trials on neoadjuvant chemotherapy and chemo-radiotherapy as a therapeutic approach for locally advanced gastric cancer have been performed. Even if more data are necessary to define the roles of these approaches, the results of preoperative treatments in the combined treatment of gastric adenocarcinoma are encouraging because this approach has led to a higher rate of curative surgical resection. Owing to the results of most recent randomized phase III studies, neoadjuvant chemotherapy for locally advanced resectable gastric cancer has satisfied the determination of level I evidence. Remaining concerns pertain to the choice of the optimal therapy regimen, strict patient selection by accurate pre-operative staging, standardization of surgical procedures, and valid criteria for response evaluation. New well-designed trials will be necessary to find the best therapeutic approach in pre-operative settings and the best way to combine old-generation chemotherapeutic drugs with new-generation molecules.

Neoadjuvant radiation therapy does not increase perioperative morbidity among patients undergoing gastrectomy for gastric cancer

BACKGROUND

Neoadjuvant radiation therapy (RT) as a component of the multimodality treatment of gastric cancer has demonstrated promising results. Data regarding its effect on perioperative safety are limited.

METHODS

Adults undergoing gastrectomy for gastric cancer in the 2005-2011 National Surgical Quality Improvement Program were included. Groups were defined by neoadjuvant RT use, and then propensity-matched based on preoperative variables. Multivariable logistic regression was performed to assess neoadjuvant RT as an independent predictor of outcomes.

RESULTS

Among 2,764 patients identified, 55 (2.0%) were treated with neoadjuvant RT. Patients who received neoadjuvant RT were more likely to have received preoperative chemotherapy and steroids, and experienced weight loss (all P < 0.01). After matching, however, there were no preoperative differences. At time of surgery, total (vs. partial) gastrectomy was more common among patients who underwent neoadjuvant RT (70.9 vs. 46.7%, P < 0.01), and operative time was longer (290 vs. 236 min, P < 0.01). There were no differences in overall complications (23.6 vs. 29.7%, P = 0.49) or 30-day mortality (3.6 vs. 3.6%, P = 0.99).

CONCLUSIONS

Neoadjuvant RT was not associated with increased morbidity or mortality following resection for gastric cancer. These findings support the ongoing investigation of neoadjuvant RT as part of the multidisciplinary management of resectable gastric cancer.

Optimal management of resectable gastric adenocarcinoma

The worldwide incidence of gastric adenocarcinoma has rapidly declined in the past century, but gastric cancer remains the fifth most common malignancy in the world. Approximately half of all cases of gastric cancer are diagnosed in Eastern Asia. In this review, we provide an overview of the landmark studies investigating neoadjuvant and adjuvant therapies in resectable gastric cancer and highlight ongoing efforts to define optimal population-adapted management strategies.

Local hyperthermia combined with radiotherapy and-/or chemotherapy: recent advances and promises for the future

Hyperthermia, one of the oldest forms of cancer treatment involves selective heating of tumor tissues to temperatures ranging between 39 and 45°C. Recent developments based on the thermoradiobiological rationale of hyperthermia indicate it to be a potent radio- and chemosensitizer. This has been further corroborated through positive clinical outcomes in various tumor sites using thermoradiotherapy or thermoradiochemotherapy approaches. Moreover, being devoid of any additional significant toxicity, hyperthermia has been safely used with low or moderate doses of reirradiation for retreatment of previously treated and recurrent tumors, resulting in significant tumor regression. Recent in vitro and in vivo studies also indicate a unique immunomodulating prospect of hyperthermia, especially when combined with radiotherapy. In addition, the technological advances over the last decade both in hardware and software have led to potent and even safer loco-regional hyperthermia treatment delivery, thermal treatment planning, thermal dose monitoring through noninvasive thermometry and online adaptive temperature modulation. The review summarizes the outcomes from various clinical studies (both randomized and nonrandomized) where hyperthermia is used as a thermal sensitizer of radiotherapy and-/or chemotherapy in various solid tumors and presents an overview of the progresses in loco-regional hyperthermia. These recent developments, supported by positive clinical outcomes should merit hyperthermia to be incorporated in the therapeutic armamentarium as a safe and an effective addendum to the existing oncological treatment modalities.

Postoperative chemoradiotherapy vs. preoperative chemoradiotherapy for locally advanced (operable) gastric cancer: clarifying the role and technique of radiotherapy

BACKGROUND

Worldwide, almost one million new cases of stomach cancer were diagnosed in 2012, making it the fifth most common cancer, and the third leading cause of cancer deaths. The current tumor node metastasis (TNM) staging system represents a consensus between the East and the West, and will serve as a strong foundation upon which to build future evidence. In this review article, we first discuss the definition and optimal surgery for locally advanced gastric cancer, followed by the general principles when considering a pre vs. postoperative radiotherapy (RT) strategy. We then provide a synthesis of the existing randomized trial evidence in an attempt clarify the role of pre and postoperative RT in the management of locally advanced gastric cancer.

METHODS

A Medline search 1966-Jun 2014 was undertaken. Randomized trials including patients with locally advanced gastric cancer (using established definitions), comparing RT [with or without chemotherapy (CT)], with surgery alone or other treatment modalities were included. Systematic reviews and evidence based practice guidelines that include this body of primary studies were preferentially discussed. Medline, Cochrane Library, Clinicaltrial.gov, Guidelines Clearinghouse were searched.

RESULTS

Sixteen randomized trials, three systematic reviews and one practice guideline were included as the evidence base. In this group of studies, two reports compared postoperative chemoradiotherapy (CRT) with surgery alone. Driven predominantly by INT0116, they established the role of postoperative CRT to provide a survival benefit in a patient group that underwent surgery with predominantly D0-1 dissections. Preoperative RT (four studies) showed promise for survival benefit but the risks of bias in these trials were high. Postoperative CRT compared with CT alone (eight trials) showed no survival benefit with the addition of radiation although some evidence of activity can be observed with improved local regional control.

CONCLUSIONS AND FUTURE DIRECTIONS

Technical expertise to enable the delivery of high quality RT to complex target volumes as is required in gastric cancer, and surgical standards to ensure the delivery of high quality surgery, have matured in recent years. Six trials with large sample sizes are currently ongoing to better define the role of preoperative CRT (two studies) and postoperative CRT (four studies), when used in conjunction with high quality surgery and RT, and contemporary CT regimens. The moderate likelihood of locoregional recurrences and the favorable therapeutic ratio with using RT preoperatively in other settings, provide optimism that preoperative CRT would have a pivotal role to play in locally advanced gastric cancer. Active accrual into ongoing trials is strongly encouraged.

Survival benefit and additional value of preoperative chemoradiotherapy in resectable gastric and gastro-oesophageal junction cancer: a direct and adjusted indirect comparison meta-analysis

Several phase I/II studies of chemoradiotherapy for gastric cancer have reported promising results, but the significance of preoperative radiotherapy in addition to chemotherapy has not been proven. In this study, a systematic literature search was performed to capture survival and postoperative morbidity and mortality data in randomised clinical studies comparing preoperative (chemo)radiotherapy or chemotherapy versus surgery alone, or preoperative chemoradiotherapy versus chemotherapy for gastric and/or gastro-oesophageal junction (GOJ) cancer. Hazard ratios (HRs) for overall mortality were extracted from the original studies, individual patient data provided from the principal investigators of eligible studies or the earlier published meta-analysis. The incidences of postoperative morbidities and mortalities were also analysed. In total 18 studies were eligible and data were available from 14 of these. The meta-analysis on overall survival yielded HRs of 0.75 (95% CI 0.65-0.86, P < 0.001) for preoperative (chemo)radiotherapy and 0.83 (95% CI 0.67-1.01, P = 0.065) for preoperative chemotherapy when compared to surgery alone. Direct comparison between preoperative chemoradiotherapy and chemotherapy resulted in an HR of 0.71 (95% CI 0.45-1.12, P = 0.146). Combination of direct and adjusted indirect comparisons yielded an HR of 0.86 (95% CI 0.69-1.07, P = 0.171). No statistically significant differences were seen in the risk for postoperative morbidity or mortality between preoperative treatments and surgery alone, or preoperative (chemo)radiotherapy and chemotherapy. Preoperative (chemo)radiotherapy for gastric and GOJ cancer showed significant survival benefit over surgery alone. In comparisons between preoperative chemotherapy and (chemo)radiotherapy, there is a trend towards improved survival when adding radiotherapy, without increased postoperative morbidity or mortality.

Radiotherapy for gastric cancer: a systematic review and meta-analysis

There have been many trials trying to prove the benefit of radiotherapy for gastric cancer; however, the results were either inclusive or controversial. The purpose of the study was to elucidate the effect of radiotherapy on gastric cancer delivered as perioperative or palliative treatment. We conducted systematic searches for trials exploring the effect of radiotherapy on gastric cancer. In the subgroup of patients receiving preoperative radiotherapy for gastric cancer, a significant benefit was found on 10-year overall survival with a hazard ratio (HR) of 0.75 (95% confidence interval (CI), 0.61 to 0.91); however, the benefit on 5-year overall survival was not proven (HR, 0.68; 95%CI, 0.45 to 1.01). There are also no significant differences in resection rate and radical resection rate between group of patients receiving radiotherapy and control group with a relative risk (RR) of 1.06 (95%CI, 0.99 to 1.13) and 1.12 (95%CI 0.93 to 1.36), respectively. In the subgroup of patients receiving postoperative radiotherapy for gastric cancer, survival benefits were found on 3- and 5-year progression-free survival with HR of 0.69 (95%CI, 0.53 to 0.90) and HR of 0.70 (95%CI, 0.61 to 0.80), respectively. Survival benefits of adjuvant radiotherapy on 3- and 5-year progression-free survival were also found; nonetheless, there was no evidence of significant difference in 3-year overall survival (HR, 0.70; 95%CI, 0.61 to 1.01). The effect of radiotherapy on 5-year overall survival was also quite controversial. In short, gastric cancer patients could benefit from radiotherapy both in the form of preoperative radiotherapy and postoperative radiotherapy.

Who benefits from adjuvant radiation therapy for gastric cancer? A meta-analysis

PURPOSE

Large randomized trials have demonstrated significant survival benefits with the use of adjuvant chemotherapy or chemoradiation therapy for gastric cancer. The importance of adjuvant radiation therapy (RT) remains unclear. We performed an up-to-date meta-analysis of randomized trials testing the use of RT for resectable gastric cancer.

METHODS AND MATERIALS

We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for randomized trials testing adjuvant (including neoadjuvant) RT for resectable gastric cancer. Hazard ratios describing the impact of adjuvant RT on overall survival (OS) and disease-free survival (DFS) were extracted directly from the original studies or calculated from survival curves. Pooled estimates were obtained using the inverse variance method. Subgroup analyses were performed to determine whether the efficacy of RT varies with chemotherapy use, RT timing, geographic region, type of nodal dissection performed, or lymph node status.

RESULTS

Thirteen studies met all inclusion criteria and were used for this analysis. Adjuvant RT was associated with a significant improvement in both OS (HR = 0.78, 95% CI: 0.70-0.86, P<.001) and DFS (HR = 0.71, 95% CI: 0.63-0.80, P<.001). In the 5 studies that tested adjuvant chemoradiation therapy against adjuvant chemotherapy, similar effects were seen for OS (HR = 0.83, 95% CI: 0.67-1.03, P=.087) and DFS (HR = 0.77, 95% CI: 0.91-0.65, P=.002). Available data did not reveal any subgroup of patients that does not benefit from adjuvant RT.

CONCLUSION

In randomized trials for resectable gastric cancer, adjuvant RT provides an approximately 20% improvement in both DFS and OS. Available data do not reveal a subgroup of patients that does not benefit from adjuvant RT. Further study is required to optimize the implementation of adjuvant RT for gastric cancer with regard to patient selection and integration with systemic therapy.

Neoadjuvant or adjuvant therapy for resectable gastric cancer: a systematic review and practice guideline for North America

BACKGROUND

Gastric cancer is a global health problem accounting for 10% of all new cancer cases and 12% of all cancer deaths worldwide. Many clinical trials and meta-analyses have explored the value of neoadjuvant or adjuvant chemotherapy and radiation therapy in gastric cancer; however, these studies have produced conflicting results. The purpose of this guidance document was to determine whether patients with resectable gastric cancer should receive neoadjuvant or adjuvant therapy in addition to surgery. Outcomes of interest were overall survival, disease-free survival, and adverse events.

METHODS

A systematic review was undertaken to inform recommendations regarding neoadjuvant and adjuvant therapy in resectable gastric cancer in Ontario, Canada. MEDLINE and EMBASE databases, as well as American Society of Clinical Oncology (ASCO) annual meeting proceedings and American Society for Therapeutic Radiology and Oncology (ASTRO) proceedings were systematically searched from 2002 to 2010. Oral fluoropyrimidine trials were excluded owing to the unavailability of these agents in North America.

RESULTS

Overall, 22 randomized controlled trials (RCTs), 13 meta-analyses, and two secondary analyses were included. The systematic review informed the development of a clinical practice guideline with the following recommendations. Postoperative 5-fluorouracil-based chemoradiotherapy based on the Macdonald approach or perioperative ECF (epirubicin, cisplatin, fluorouracil) chemotherapy based on the Cunningham/MAGIC (Medical Research Council Adjuvant Gastric Infusional Chemotherapy) approach are both acceptable standards of care in North America. Choice of treatment should be made on a case-by-case basis. Adjuvant chemotherapy is a reasonable option for those patients for whom the Macdonald and MAGIC protocols are contraindicated. All patients with resectable gastric cancer should undergo a pretreatment multidisciplinary assessment to determine the best plan of care.

CONCLUSIONS

Overall survival in patients with resectable gastric cancer is significantly improved with the use of either postoperative chemoradiation (Macdonald approach) or perioperative ECF (MAGIC protocol).

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

Neoadjuvant chemotherapy for locally advanced gastric cancer: With or without radiation

The role of perioperative chemotherapy for gastric cancer has been established for gastric cancers in their advanced stage. In most parts of the world, even in Japan and Korea, local recurrence of gastric cancer following curative resection remains a problem. Should radiation be added to chemotherapy to achieve better local and regional control? What is the current evidence? What are the concerns regarding neoadjuvant chemoradiation in terms of safety, efficacy and survival benefit? After a serious review of the literature, the authors conclude that it is still too early to get a definitive answer but radiation seems promising. It may bring a higher pathological response rate. Rationally, more high level clinical trials are needed to confirm the role of radiotherapy in the neoadjuvant setting or to ascertain subsets of patients who may benefit from it. It is of note that surgeons should pay attention to possible complicated circumstances following radiotherapy, maintain proper nutrition status and minimize the occurrence of postoperative complications. As few data are available in Japan and Korea, interpretation and implementation of neoadjuvant radiation or chemoradiation should be done with caution.

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.

Evidence based radiation therapy for locally advanced resectable and unresectable gastric cancer

Despite the fact that gastric cancer is decreasing in incidence in the United States, it remains one of the most commonly diagnosed and most fatal cancers worldwide. In localised disease, surgery remains the cornerstone of treatment. Nevertheless, the low overall survival rates at 5 years due to locoregional and distant recurrences has led to a large debate regarding the role of radiation therapy and chemotherapy in addition to curative resection. Recent data have shown that, even with improved surgical techniques, locoregional failure rates in these patients ranged between 57% and 88%. Failures were noted in the gastric bed, regional nodes, gastric remnant, anastomosis and duodenal stump, all of which can be encompassed in a regional radiation field, indicating the need of further locoregional treatment. In this article, a comprehensive literature review of the reliable medical databases of PubMed and Cochrane is made and we present all available information on the role of radiation therapy in the preoperative and postoperative setting of gastric cancer. Data reported show that in locally advanced gastric cancer the addition of radiation therapy post surgery has significantly improved disease-free survival as well as overall survival. Moreover, in unresectable gastric cancer, the combination of radiation therapy with chemotherapy has significantly improved mean and overall survival rates. The role of radiation therapy in patients with resectable gastric cancer is being further evaluated in ongoing phase III trials.

Improved survival in patients with lymph node-positive gastric cancer who received preoperative radiation: an analysis of the Surveillance, Epidemiology, and End Results database

BACKGROUND

Several trials have been conducted to determine the feasibility of preoperative radiotherapy (RT) for gastric cancer. However, the absolute benefit from radiotherapy remains to be defined. In this study, the authors examined the use of preoperative RT (Pre-RT) and postoperative RT (PORT) in patients with gastric cancer from the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

The overall survival of patients who had nonmetastatic, resected gastric cancer between 2000 and 2006 was analyzed from the SEER database. Kaplan-Meier survival curves comparing Pre-RT, PORT, and no RT (No-RT) were analyzed using the log-rank test. A multivariate analysis (MVA) was conducted using Cox proportional hazards regression.

RESULTS

The authors identified 10,251 patients. There was no survival benefit for patients who received Pre-RT or PORT compared with No-RT patients for the entire cohort. Conversely, among lymph node-positive patients, there was a significant survival benefit from both Pre-RT and PORT compared with No-RT (log-rank test: PORT, P < .0001; Pre-RT, P = .0261). The median survival and 5-year overall survival among lymph node-positive patients were 22 months and 24%, respectively, for Pre-RT;29 months and 34%, respectively, for PORT; and 19 months and 20%, respectively, for No-RT. MVA demonstrated that Pre-RT, PORT, and removing ≥ 15 lymph nodes were independent predictors of improved survival, whereas tumor classification, lymph node status, tumor size, and tumor location were independent predictors of death.

CONCLUSIONS

The current results supported the use of Pre-RT in select patients with gastric cancer. However, additional trials will be needed to confirm these findings.

Updating controversies on the multidisciplinary management of gastric cancer

The rates of relapse and death remain high in gastric cancer patients, especially in advanced stages. Local relapses in the tumour bed and regional lymph nodes, peritoneal spread as abdominal carcinomatosis, and distant metastasis are common mechanisms of failure after a R0 resection. To overcome this, a multidisciplinary approach has been prompted. In recent years, multidisciplinary treatment has been strengthened by some randomised controlled trials and it is now considered the standard by most groups, although the improvement in long-term survival rates achieved is still limited. This new therapeutic approach in gastric cancer is rapidly evolving and has led to a series of controversies on the best strategy to follow. Some of these controversies are discussed in this paper.

Survival after radiotherapy in gastric cancer: systematic review and meta-analysis

BACKGROUND AND PURPOSE

A systematic review and meta-analysis was performed to assess the impact of radiotherapy on both 3- and 5-year survival in patients with resectable gastric cancer.

METHODS

Randomized Clinical Trials (RCTs) in which radiotherapy, (preoperative, postoperative and/or intraoperative), was compared with surgery alone or surgery plus chemotherapy in resectable gastric cancer were identified by searching web-based databases and supplemented by manual examination of reference lists. Meta-analysis was performed using Risk Ratios (RRs). Random or fixed effects models were used to combine data. The methodological quality was evaluated by Chalmers' score.

RESULTS

Radiotherapy had a significant impact on 5-year survival. Using an intent to treat (ITT) and a Per Protocol (PP) analysis, the overall 5-year RR was 1.26 (95% CI: 1.08-1.48; NNT=17) and 1.31 (95% CI: 1.04-1.66; NNT=13), respectively. Although the quality of the studies was variable, the data were consistent and no clear publication bias was found.

CONCLUSION

This meta-analysis showed a statistically significant 5-year survival benefit with the addition of radiotherapy in patients with resectable gastric cancer. Radiotherapy remains a standard component in the treatment of resectable gastric cancer and new RCTs need to address the impact of new conformal radiotherapy technologies.

The Kadota Fund International Forum 2004--clinical group consensus

The results from experimental studies indicate that hyperthermia is both an effective complementary treatment to, and a strong sensitiser of, radiotherapy and many cytotoxic drugs. Since the first international hyperthermia conference in 1975, Washington DC, techniques to increase tumour temperature have been developed and tested clinically. Hyperthermia can be applied by several methods: local hyperthermia by external or internal energy sources, perfusion hyperthermia of organs, limbs, or body cavities, and whole body hyperthermia. The clinical value of hyperthermia in combination with other treatment modalities has been shown by randomised trials. Significant improvement in clinical outcome has been demonstrated for tumours of the head and neck, breast, brain, bladder, cervix, rectum, lung, oesophagus, for melanoma and sarcoma. The addition of hyperthermia resulted in remarkably higher (complete) response rates, accompanied by improved local tumour control rates, better palliative effects, and/or better overall survival rates. Toxicity from hyperthermia cannot always be avoided, but is usually of limited clinical relevance. In spite of these good clinical results, hyperthermia has received little attention. Problems with acceptance concern the limited availability of equipment, the lack of awareness concerning clinical results, and the lack of financial resources. In this paper the most relevant literature describing the clinical effects of hyperthermia is reviewed and discussed, and means to overcome the lack of awareness and use of this modality is described.

The impact of radiotherapy on survival in resectable gastric carcinoma: a meta-analysis of literature data

BACKGROUND

The benefit of external radiotherapy for gastric carcinoma has been extensively studied, but data on survival are still equivocal.

OBJECTIVE

To assess the effectiveness of surgery combined with preoperative radiotherapy or postoperative chemoradiotherapy in the reduction of all-cause mortality in patients with resectable gastric carcinoma.

METHODS

Computerised bibliographic searches of MEDLINE and CANCERLIT (1970-2006) were supplemented with hand searches of reference lists.

STUDY SELECTION

Studies were included if they were randomised controlled trials (RCTs) comparing mortality of surgery combined with preoperative radiotherapy or postoperative chemoradiotherapy to surgery alone, and if they included patients with histologically-proven gastric adenocarcinoma without metastases. Nine eligible RCTs, 4 of preoperative radiotherapy (832 patients) and 5 of postoperative chemoradiotherapy (869 patients), were identified and included in the meta-analysis.

DATA EXTRACTION

Data on study populations, interventions, and outcomes were extracted from each RCT according to the intention to treat method by three independent observers and combined using the DerSimonian and Laird method.

RESULTS

Surgery combined with preoperative radiotherapy compared to surgery alone significantly reduced the 3-year (OR 0.57; 95% CI 0.43-0.76: p=0.0001) and 5-year (OR 0.62; 95% CI 0.46-0.84; p=0.002) mortality rate. A significant reduction of the 5-year (OR 0.45; 95% CI 0.32-0.64; p<0.00001) mortality rate was observed when surgery followed by chemoradiotherapy was compared to surgery alone.

CONCLUSIONS

In patients with resectable gastric carcinoma, adjuvant radiotherapy significantly reduces 3-year and 5-year all-cause mortality, but the magnitude of the benefit is relatively small. Available evidence is inadequate to determine whether postoperative chemoradiotherapy is superior to preoperative radiotherapy.

Gastric cancer: standards for the 21st century

Although the incidence of gastric cancer has been decreasing in the United States, it remains a leading cause of cancer death in the world, only lung cancer causes more deaths worldwide. The combination of relatively low prevalence, lack of pathognomonic symptoms, and lack of defined risk factors are associated with a delay in diagnosis leading to a dismal prognosis. For localized disease, surgery remains a cornerstone of treatment but much controversy remains regarding optimal peri-operative therapy. For advanced disease, several new agents and new combination chemotherapies have offered encouraging results. This paper seeks to review the major topics surrounding gastric cancer and cover the results of recently reported and ongoing trials.

Adjuvant and neoadjuvant therapy for gastric cancer

Although the incidence of gastric cancer is decreasing, it remains a significant source of cancer-related mortality. Surgery remains the best chance for cure from gastric cancer. Adjuvant and neoadjuvant therapy have played increasing roles in attempting to reduce the disease-specific mortality and prolong survival. In this article, the authors review the literature and summarize the salient points regarding the roles of adjuvant and neoadjuvant therapy for gastric cancer.

Curative treatment of gastric cancer: towards a multidisciplinary approach?

Despite marked decreases in incidence over the last century, particularly in developed countries, gastric cancer is still the second-most common tumor worldwide. Surgery remains the gold standard for the cure of locoregional disease. However, in most countries, the diagnosis is made at an advanced stage, and the 5-year survival for surgically resectable disease stays far below 50%. The efficacy of chemotherapy and/or radiation therapy in addition to surgery has been actively studied over the last 30 years. Unfortunately, with few exceptions, most studies of adjuvant therapy in gastric cancer have given deceiving results. The purpose of this review is to address the reasons for our failure to objectivate an improvement in the cure of gastric cancer with adjuvant treatment in most trials, and to consider potential solutions. The low efficacy of chemotherapy regimens available up to now may have hampered our progress. In addition, many previous studies suffered limitations of design or methodology (e.g. low accrual, inadequate disease stage selection, inadequate surgical treatment) that may have obscured a treatment effect. Furthermore, the reduced treatment tolerance of post-gastrectomy patients, perhaps due to their poor nutritional status, results in decreased or delayed adjuvant systemic therapy, with potential adverse consequences in its efficacy. Among potential solutions, the arrival of new drugs, taxanes and topoisomerase I inhibitors in particular, which have shown encouraging results in metastatic disease, may increase the impact of chemotherapy in a multidisciplinary treatment approach. Pre-treatment with chemotherapy and/or radiation therapy prior to surgery may also be advantageous, averting the problems associated with post-surgical treatment. Such an approach has been shown to be feasible in phase II studies, and is relatively well tolerated by patients. Several carefully designed randomized phase III trials are underway to answer this question.

Preoperative radiotherapy in combination with metronidazole for resectable gastric cancer: long-term results of a phase 2 study

AIM

Surgery remains the main treatment of stomach carcinoma. Poor long-term survival mandates the study of other techniques. An original treatment scheme with preoperative radiotherapy and metronidazole as a radiosensitizer is reported here.

METHODS

Between 1982 and 1988, MRRC RAMS carried out a prospective clinical trial of preoperative radiotherapy (20 Gy/5 days) in combination with metronidazole (given orally, 3 times, 5 gms per metre(2)). Of 91 patients who received preoperative radiotherapy, 67 patients were operated on with curative intent and were eligible for further analysis.

RESULTS

Acute gastro-intestinal toxicity was significant but manageable without surgery delay in most cases. There were 4 postoperative deaths. Overall 5-year, 10-year survival and median survival were 46%, 36% and 46 months. Serosal and nodal involvement were the most significant adverse prognostic factors. Tumours confined to the gastric wall, node negative cases, middle and distal location, differentiated tumours, female sex and age more than 50 years were associated with relatively good long-term results: overall 5-year survival was 50% or better, overall 10-year survival was 40% or better.

CONCLUSION

The combined treatment showed significant but manageable acute toxicity. The long-term results seem encouraging and support further investigations in multimodal treatment of gastric cancer.

Neoadjuvant radiochemotherapy for locally advanced gastric cancer: a phase I-II study

BACKGROUND

To study in a phase I-II trial the maximum tolerated dose, the toxicity, and the tolerance of adding radiotherapy to systemic chemotherapy administered preoperatively in patients with locoregionally advanced gastric adenocarcinoma.

PATIENTS AND METHODS

Patients with adenocarcinoma of the stomach (T(3)(-)(4)N(any) or T(any)N+), performance status </=1, normal hematological, hepatic and renal functions received two cycles of cisplatin 100 mg/m(2) on day 1, 5-FU 800 mg/m(2) on days 1 to 4 and leucovorin 60 mg b.i.d. on days 1 to 4 q3w, concomitantly with radiation therapy escalated in three dose tiers (31.2, 38.4 and 45.6 Gy).

RESULTS

Nineteen patients were accrued and 18 completed neoadjuvant therapy. Major toxicity consisted of grade 3/4 leucopenia and mucositis in 89% and 36% of the patients, respectively. Only one episode of febrile neutropenia was recorded. Dose level number 2 (38.4 Gy) with the chemotherapy given q4w is the recommended dose level. All patients were subsequently operated and no fatalities occurred. Pathological assessment showed one complete and eight partial responses. Two- and 3-year relapse-free survival rates were 57% and 50%, respectively. Only one patient relapsed locally. The peritoneum was the most frequent site of relapse.

CONCLUSIONS

This neoadjuvant therapeutic program is relatively well tolerated, does not seem to increase the operative risk, and might increase the locoregional control of the disease. The frequency of peritoneal involvement in relapsing patients underscores the need for a more effective systemic treatment.

[Chemoradiotherapy in the adjuvant treatment of gastric adenocarcinomas: real progress?]

Frequency of local and distant failures after gastrectomy has led to extended lymph nodes dissection to obtain a better locoregional control. However, five year survival rates were not significantly different between patients undergoing D2 and D1 lymphadenectomy, and higher morbidity and post operative deaths were reported in large randomised trials (respectively 25% vs 48% and 4 vs 13%). Additionally, several metanalysis failed to demonstrate a significant survival advantage with adjuvant chemotherapy. The results of the first trial demonstrating one advantage to adjuvant post-operative chemoradiotherapy should modify the standard care. Disease free and overall survival after surgery alone and after surgery and concurrent chemoradiotherapy were respectively 31% vs 48% and 41% vs 50%. The intergroup trial demonstrate that better local control improve survival if radiation fields include stamps, tumour bed, proximal nodal chains and nodes corresponding to D2 extended lymph nodes dissection. Treatment was feasible with few severe toxic effects (1%). Of the 281 patients, 17% stopped treatment because toxic effects. Technical modalities of radiotherapy and post-operative nutrition support, which are critical points of interest for this treatment, are also discussed.

Heating the patient: a promising approach?

There is a clear rationale for using hyperthermia in cancer treatment. Treatment at temperatures between 40 and 44 degrees C is cytotoxic for cells in an environment with a low pO(2) and low pH, conditions that are found specifically within tumour tissue, due to insufficient blood perfusion. Under such conditions radiotherapy is less effective, and systemically applied cytotoxic agents will reach such areas in lower concentrations than in well perfused areas. Therefore, the addition of hyperthermia to radiotherapy or chemotherapy will result in at least an additive effect. Furthermore, the effects of both radiotherapy and many drugs are enhanced at an increased temperature. Hyperthermia can be applied by several methods: local hyperthermia by external or internal energy sources, regional hyperthermia by perfusion of organs or limbs, or by irrigation of body cavities, and whole body hyperthermia. The use of hyperthermia alone has resulted in complete overall response rates of 13%. The clinical value of hyperthermia in addition to other treatment modalities has been shown in randomised trials. Significant improvement in clinical outcome has been demonstrated for tumours of the head and neck, breast, brain, bladder, cervix, rectum, lung, oesophagus, vulva and vagina, and also for melanoma. Additional hyperthermia resulted in remarkably higher (complete) response rates, accompanied by improved local tumour control rates, better palliative effects and/or better overall survival rates. Generally, when combined with radiotherapy, no increase in radiation toxicity could be demonstrated. Whether toxicity from chemotherapy is enhanced depends on sequence of the two modalities, and on which tissues are heated. Toxicity from hyperthermia cannot always be avoided, but is usually of limited clinical relevance. Recent developments include improvements in heating techniques and thermometry, development of hyperthermia treatment planning models, studies on heat shock proteins and an effect on anti-cancer immune responses, drug targeting to tumours, bone marrow purging, combination with drugs targeting tumour vasculature, and the role of hyperthermia in gene therapy. The clinical results achieved to date have confirmed the expectations raised by results from experimental studies. These findings justify using hyperthermia as part of standard treatment in tumour sites for which its efficacy has been proven and, furthermore, to initiate new studies with other tumours. Hyperthermia is certainly a promising approach and deserves more attention than it has received until now.

Concentrated preoperative radiotherapy for resectable gastric cancer: 20-years follow-up of a randomized trial

BACKGROUND AND OBJECTIVES

The role of radiation therapy in resectable gastric cancer is questionable. To study the value of concentrated preoperative radiotherapy, a randomized clinical trial had been carried out.

METHODS

From 1974 to 1978, 152 patients were randomized and underwent exploratory laparotomy; in 50 patients curative surgery was not possible, while 102 patients satisfied protocol requirements and entered in the trial. Patients in the experimental group were treated with preoperative radiotherapy (20 Gy/5 days) and subtotal or total gastrectomy. Patients in the control group underwent surgery alone.

RESULTS

Study showed acceptable tolerance of radiotherapy regime with no increase of postoperative mortality and morbidity. There was no significant difference in survival between the two treatment groups (chi 2 = 0.349, df = 1, P = 0.555). Subset analysis also failed to demonstrate significant survival advantages of the combined treatment; however, some positive trends were seen in patients with locally advanced gastric cancer.

CONCLUSIONS

Concentrated preoperative radiotherapy in the dose of 20 Gy is safe and feasible, but seems to be insufficient to improve survival in gastric cancer patients. However, the results are promising in selected subgroups of patients, which encourages future trials with adjuvant radiation therapy.

Randomized clinical trials in gastric cancer

A total of 52 prospective, randomized controlled trials (RCT), published from 1975 to 2000, were reviewed for gastric cancer. The primary focus of these efforts has been the use of chemotherapy in patients with metastatic or locally advanced disease, accounting for 23 of the 52 trials. In comparison, there were only six surgical trials evaluating the extent of either primary resection or lymphadenectomy.

Extended surgical resection in T4 gastric cancer

BACKGROUND

Some physicians still consider invasion of adjacent organs by the carcinoma of stomach as a sign of incurable disease.

METHODS

This retrospective study has been done with particular reference to 353 T4 gastric cancer patients who underwent combined gastrectomies with adjacent organs.

RESULTS

Subtotal gastrectomy was performed in 237 (67.1%) patients and total gastrectomy was performed in 116 (32.9%) patients. Organs most commonly resected with the stomach were the transverse colon in 159 (45%) cases, the tail of pancreas and spleen in 150 (42.5%), the left lobe of liver in 101 (28.5%), and the head of pancreas in 37 (10.5%) patients. A total of 110 postoperative complications occurred in this subset of patients corresponding to a complication rate of 31.2%. A total of 48 postoperative deaths occurred in this subset of patients corresponding to a mortality rate of 13.6%. The 5-year survival rate for all patients who underwent combined gastrectomy with adjacent organs was 25%. Of the node-negative T4 gastric cancer resections, 37% survived 5 years whereas the T4 node-positive resections have only a 15% 5-year survival.

CONCLUSIONS

Patients who present with T4 gastric cancer (about 20% of the patient population) will benefit from aggressive en bloc surgical resection and should not be considered unresectable.

Carcinoma of the stomach following the Chernobyl nuclear accident

Medical consequences of many nuclear accidents on humans are well studied, but the results pertaining to gastric cancer patients who were exposed to radiation as a result of the Chernobyl nuclear accident have not been analysed. In this study, the outcome of the surgical treatment of 68 gastric cancer patients who were exposed to radiation as a result of the Chernobyl nuclear accident was compared with that of 117 consecutive gastric cancer patients from uncontaminated areas of the Ukraine. Patients in the study group was significantly younger than that of the control group. Comparative analysis showed the same frequency of regional metastases (65.7% versus 71.1%, P > 0.05), but a smaller number of distant metastases (23.8% versus 38.1%, P < 0.05) in the study group. 41.2% of patients in the study group underwent total gastrectomy compared to 19.6% of patients in the control group (P = 0.002). Postoperative complications developed in 13.2% of patients in the study group, while postoperative mortality in the study group was 7.3% compared to 1.7% in the control group. A significant decrease in CD16 cells was noted in patients from the study group following the operative procedure. Young age, invasive tumours with smaller number of distant metastases, frequent necessity for total gastrectomy and combined operations with adjacent organs, a higher level of postoperative morbidity and mortality and low levels of natural killer cells (CD16+) with a tendency to decrease after surgery are characteristic of patients with carcinoma of the stomach affected by the Chernobyl accident.