Endoscopic ultrasound in restaging of esophageal cancer after neoadjuvant chemoradiation

Updates on esophageal and gastric cancers

Esophageal and gastric cancers are both common and deadly. Patients present most often after disease progression and survival is therefore poor. Due to demographic variability and recent changes in disease incidence, much emphasis has been placed on studying risk factors for both esophageal and gastric cancers. However, with increasing understanding of these diseases, low survival rates persist and continued intensive studies are necessary to optimize treatment plans. This review article discusses updates in the evolving epidemiology, clinical presentation, risk factors, and diagnostic and treatment modalities of esophageal and gastric cancers.

Response monitoring of neoadjuvant therapy using CT, EUS, and FDG-PET

Neoadjuvant or adjuvant multimodality therapy in oesophageal cancer is introduced in an effort to improve prognosis. However, in a substantial fraction of patients there is no response to this non-surgical therapy. Non-invasive imaging modalities such as computed tomography (CT), endoscopic ultrasound (EUS) and 18F-2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) have been evaluated for assessing patient response to therapy, and these are described in this review. Currently, FDG-PET seems to be the best available tool for neoadjuvant therapy response assessment in oesophageal cancer.

The endoscopic diagnosis and staging of oesophageal adenocarcinoma

The endoscopic evaluation of patients with oesophageal adenocarcinoma does not only serve the purpose of diagnosing the lesion and obtaining biopsies for histological evaluation: a systematic description of advanced lesions is also required to guide further therapeutic decisions. New endoscopic imaging modalities hold the promise of better endoscopic detection of early cancer and its precursor lesions in Barrett's oesophagus. Video-autofluorescence and narrow band imaging are the most promising techniques in this respect. The former may be used as a 'red flag' technique, identifying lesions that remain occult with white light endoscopy; the latter may be used as a targeted imaging technique, allowing for detailed inspection of the mucosal and vascular patterns that may help to distinguish early neoplasia from non-dysplastic tissue. Currently, prototypes are under investigation that combine high-resolution endoscopy, narrow band imaging and video-autofluorescence in one endoscopy system. Endoscopic ultrasonography (EUS) is superior to any other imaging modality in the assessment of local tumour infiltration of oesophageal adenocarcinoma and locoregional lymph nodes status. EUS allows for the identification of patients with advanced disease who are unlikely to benefit from attempts at curative surgery and in whom a conservative palliative treatment is indicated. EUS may also play a role in the selection of patients for local endoscopic treatment of early oesophageal cancer. EUS guided fine needle aspiration (EUS-FNA) of locoregional lymph nodes is safe with a high sensitivity and an impeccable specificity for assessment of malignant involvement. The indications for EUS-FNA of lymph nodes, however, depend on local treatment protocols: caeliac nodes (M1a) and lymph nodes located at or above the subcarinal area are the most widely used indications. In addition, it may be important if the choice for specific treatment protocols (e.g. neoadjuvant chemoradiotherapy) depends on lymph node status.

Neoadjuvant chemotherapy for oesophageal cancer: The need for accurate response prediction and evaluation

Primary surgical resection for locally advanced oesophageal cancer is associated with systemic failure and poor survival due to presence of micrometastatic disease at the time of diagnosis. Neoadjuvant chemotherapy prior to surgical resection aims to downstage these locally advanced tumours. A review of reported randomised controlled trials has shown only one sufficiently powered trial with a survival advantage for cisplatin-based chemotherapy. Published meta-analyses of neoadjuvant chemotherapy trials have shown little or no overall survival benefit. A subgroup of patients with biologically favourable tumours who respond to this treatment have been consistently shown to have a survival advantage. These patients need to be differentiated from non-responders preferably at an early stage of this potentially toxic treatment. Current clinical, endoscopic and radiological methods of response evaluation are all unreliable. Response evaluation with 18FDG-PET has been shown to accurately assess the pathological response and also to predict the risk of local recurrence and overall survival. The development of integrated PET/CT imaging may enhance the accuracy of this response evaluation. In the future, molecular markers of response prediction prior to initiation of treatment may allow the development of individualised treatment strategies. New emerging chemotherapeutic agents may prove to be more effective in eradicating micrometastatic disease.

Esophageal cancer: CT, endoscopic US, and FDG PET for assessment of response to neoadjuvant therapy--systematic review

PURPOSE

To compare diagnostic accuracy of computed tomography (CT), endoscopic ultrasonography (US), and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for assessment of response to neoadjuvant therapy in patients with esophageal cancer by using a systematic review of the literature.

MATERIALS AND METHODS

MEDLINE and EMBASE databases and Cochrane Database of Systematic Reviews were searched for relevant studies. Two reviewers independently assessed the methodological quality of each study. Summary receiver operating characteristic (ROC) analysis was used to summarize and compare the diagnostic accuracy of the three modalities.

RESULTS

Four studies with CT, 13 with endoscopic US, and seven with FDG PET met inclusion criteria. Percentages of the maximum score in regard to methodological quality ranged from 15% to 100%. Summary ROC analysis could be performed for three studies with CT, four with endoscopic US, and four with FDG PET. The maximum joint values for sensitivity and specificity were 54% for CT, 86% for endoscopic US, and 85% for FDG PET. Accuracy of CT was significantly lower than that of FDG PET (P < .006) and of endoscopic US (P < .003). Accuracy of FDG PET and that of endoscopic US were similar (P = .839). In all patients, CT was always feasible, whereas endoscopic US was not feasible in 6% of the patients, and FDG PET was not feasible in less than 1%.

CONCLUSION

CT has poor accuracy for assessment of response to neoadjuvant therapy in patients with esophageal cancer. Endoscopic US and FDG PET have equivalent good accuracy, but endoscopic US is not always feasible after chemotherapy and radiation therapy. FDG PET seems to be a promising noninvasive tool for assessment of neoadjuvant therapy in patients with esophageal cancer.

Role of endoscopic ultrasonography in the staging and follow-up of esophageal cancer

PURPOSE

To evaluate the role of endoscopic ultrasonography (EUS) in the initial staging and follow-up of esophageal cancer on the basis of a review of the published literature.

METHODS

Articles published from 1985 to 2005 were searched and reviewed using the following keywords: "esophageal cancer staging," "endoscopic ultrasound," and "endoscopic ultrasonography."

RESULTS

For initial anatomic staging, EUS results have consistently shown more than 80% accuracy compared with surgical pathology for depth of tumor invasion (T). Accuracy increased with higher stage, and was >90% for T3 cancer. EUS results have shown accuracy in the range of 75% for initial staging of regional lymph nodes (N). EUS has been invariably more accurate than computed tomography for T and N staging. EUS is limited for staging distant metastases (M), and therefore EUS is usually performed after a body imaging modality such as computed tomography or positron emission tomography. Pathologic staging can be achieved at EUS using fine-needle aspiration (FNA) to obtain cytology from suspect Ns. FNA has had greatest efficacy in confirming celiac axis lymph node metastases with more than 90% accuracy. EUS is inaccurate for staging after radiation and chemotherapy because of inability to distinguish inflammation and fibrosis from residual cancer, but a more than 50% decrease in tumor cross-sectional area or diameter has been found to correlate with treatment response.

CONCLUSION

EUS has a central role in the initial anatomic staging of esophageal cancer because of its high accuracy in determining the extent of locoregional disease. EUS is inaccurate for staging after radiation therapy and chemotherapy, but can be useful in assessing treatment response.

Endoscopic ultrasound for luminal malignancies

Luminal gastrointestinal (GI) tract cancers are responsible for substantial morbidity and mortality. Since the first pairing of ultrasonography with endoscopy in 1980, technologic advances and the increased availability of trained endosonographers have propelled endoscopic ultrasonography (EUS) to the forefront of luminal GI cancer staging. In this article we discuss the role of EUS for evaluating luminal GI cancers.

Advanced esophageal cancer

Although the prognosis for patients with early cancer is good, throughout the world the majority of patients present with advanced disease, and in them, survival is poor. Accurate staging is essential to inform prognosis; to select candidates who may be cured by surgery alone; to select patients requiring neoadjuvant therapy, especially when new protocols are being studied; and to detect patients with advanced disease who would be best served by palliative therapy.

N/A

N/A

[PET/CT for colorectal and hepatic tumors]

This contribution presents clinical and technical aspects of combining positron emission tomography (PET) and computed tomography (CT) for patients with colorectal tumors and characterization of unclear liver foci. In which manner and for which patients combined PET/CT is superior to PET or CT alone is also discussed. PET/CT can fulfil most prerequisites for imaging in pre- and postoperative management of patients with colorectal tumors and best meets the desire for optimal imaging procedures. Some of the disadvantages encountered in frequently employed CT can be overcome by the combination of PET and CT while increasing both sensitivity in detecting lesions and specificity in their characterization. Questions regarding treatment response offer an opportunity for devising novel study concepts and initiating research on new PET tracers. Although few publications are available, we are of the opinion that the combination of functional and anatomical imaging provided by PET/CT can improve both preoperative management and aftercare. To this end, however, optimum cooperation between practitioners of nuclear medicine and radiology is imperative.

Responders benefit from neoadjuvant radiochemotherapy in esophageal squamous cell carcinoma: results of a prospective phase-II trial

BACKGROUND

We present the results of a prospective phase-II-study of neoadjuvant combined radiochemotherapy followed by surgical resection in patients with histological proven locally advanced squamous cell carcinoma of the esophagus located at or above the level of the tracheal bifurcation.

METHODOLOGY

Between February 1995 and March 2000 a total of 76 patients with esophageal squamous cell carcinoma (uT3/4N0/+-categories) received simultaneous combined neoadjuvant radiochemotherapy consisting of a continuous intravenous infusion of 5-fluorouracil (300 mg/m2/day) 7 day per week concurrently with conventional fractioned external beam radiation therapy (2 Gy/day), five fractions per week up to a total dose of 30 Gy.

RESULTS

Radiochemotherapy related acute severe toxicity rate (CTC-grade-III) occurred in 34 patients, two patients died. Sixty-four patients underwent surgery with a complete resection in 48 patients. Three patients died during a 90-day post-operative course. The histopathological workup revealed no viable residual tumour cells in eight patients (ypCR) and according to the modified criteria of Mandard in 26 patients a histopathological response. Twenty-two of these patients underwent a R0-resection. The median follow-up time was 5.4 years with an overall median survival time of 20.6 months. The median survival in the 26 responders was 32.3 months versus 19.5 months in 38 non-responders (p=0.03).

CONCLUSIONS

Patients with locally advanced squamous cell carcinoma of the esophagus, who respond to preoperative neoadjuvant combined radiochemotherapy, seem to have more benefit from subsequent resection than non-responding patients.

Laparoscopic esophagectomy in the palliative treatment of advanced esophageal cancer after radiochemotherapy

BACKGROUND

Esophageal cancer is associated with a poor long-term prognosis. Only a 10% 5-year survival rate is reported. This article aims to evaluate the feasibility and efficacy of laparoscopic esophagectomy for the palliative treatment of advanced esophageal cancer (T3-T4 Nx-N1) after neoadjuvant therapy.

METHODS

From March 1998 to July 2002, 35 patients (mean age, 64.6 years; range, 35-72 years) affected by advanced cancer of the middle lower third of the esophagus came to the authors' observation. All received neoadjuvant radiochemotherapy. Of the 35 patients, 22 (62.9%) showed a positive response to treatment (>or=50% reduction of maximal cross-sectional area of the tumor), and surgical intervention was performed 4 weeks after the end of the therapy. The operations were accomplished through the laparoscopic approach and left lateral cervicotomy.

RESULTS

The mean operative time was 160 min (range, 120-260 min). One patient (4.5%) experienced a cervical anastomotic leak. Three patients (13.6%) died in the postoperative period: one of myocardial infarction and two of acute respiratory failure. The mean postoperative hospital stay was 12.1 days (range, 9-23 days). After a mean follow-up period of 20.2 months (range, 10-40 months), 13 patients (68.4%) were alive.

CONCLUSIONS

The laparoscopic approach seems to be effective for the palliative treatment of advanced esophageal cancer. Further trials will be necessary to evaluate the advantages of this technique.

Should preoperative, post-chemoradiotherapy endoscopy be routine for esophageal cancer patients?

Chemoradiation therapy is used widely for locoregional esophageal cancer. Patients with persistent disease may benefit from surgery. Preoperative esophagoscopy can identify persistent tumor but its accuracy is uncertain. The primary objective of this study is to assess the extent of agreement between esophagoscopy and surgical pathology in patients treated with neoadjuvant chemoradiation. A retrospective chart review of patients who underwent chemoradiation, preoperative endoscopy and surgery from January 1996 to December 2002 was performed. Cohen's kappa statistic was used to measure the degree of agreement between findings at endoscopic biopsy and surgical pathology. Thirty cases were identified. All patients received chemoradiation followed by surgical resection. There was insufficient agreement between tumor size (kappa 0.25, standard error 0.17, P = 0.07) and appearance (kappa 0.19, standard error 0.18, P = 0.14). Preoperative endoscopy revealed atypia/inflammation in 15 cases and dysplasia in eight. Of these 23 cases, 11 were adenocarcinomas at surgery. Only nine patients had concurrence between surgical pathology and endoscopy. The positive and negative predictive values of esophagoscopy for identifying residual tumor were 100% and 11%, respectively. Our data suggests that after chemoradiation, esophagoscopy is unreliable for excluding residual disease. The roles of other modalities need to be explored.

Comparison of linear array endoscopic ultrasound and helical computed tomography for the staging of periampullary malignancies

BACKGROUND

The purpose of this study was to compare linear array endoscopic ultrasound (EUS) and helical computed tomography (CT) scan in the preoperative local staging evaluation of patients with periampullary tumors.

METHODS

Patients evaluated with EUS and CT for suspected periampullary malignancies from 1996 to 2000 were analyzed. Surgical/pathology staging results were the reference standard.

RESULTS

Forty-eight patients (28 men and 20 women; mean age, 62 +/- 4.9 years; range, 18-90 years) were identified. Malignancy was histologically confirmed in 44 patients. Parameters evaluated included tumor size, lymph node metastases, and major vascular invasion. EUS was significantly more sensitive (100%), specific (75%), and accurate (98%) than helical CT (68%, 50%, and 67%, respectively) for evaluation of the periampullary mass (P <.05). In addition, EUS detected regional lymph node metastases in more patients than helical CT. Sensitivity, specificity, and accuracy of EUS were 61%, 100%, and 84%, in comparison to 33%, 92%, and 68%, respectively, with CT. Major vascular involvement was noted in 9 of 44 patients. EUS correctly identified vascular involvement in 100% compared with 45% with CT (P <.05).

CONCLUSIONS

Linear array EUS was consistently superior to helical CT in the preoperative local staging of periampullary malignancies.

Current status of neoadjuvant therapy for adenocarcinoma of the distal esophagus

Prospective studies dealing with preoperative therapy in adenocarcinoma of the esophagus alone are rare. The interpretation of the preferential phase II trials and a few phase III trials is complicated, as most studies include adenocarcinoma of the esophagus (i.e., Barrett's carcinoma), adenocarcinoma of the esophagogastric junction (including cardia carcinoma and subcardia carcinoma), or squamous cell carcinoma. Preoperative chemotherapy, generally well tolerated, cannot decrease the incidence of local failure beyond the level achieved with surgery alone, but it might delay systemic relapse. Preoperative radiotherapy can enhance local control, but it fails to improve overall survival. Neoadjuvant chemoradiation was demonstrated in only one randomized trail to have a survival benefit, but survival in the surgery-alone group was unusually low. Generally, survival was ameliorated in patients responding to neoadjuvant treatment. However, preoperative chemoradiation was often accompanied by a remarkable increase in postoperative morbidity and mortality. Nonresponding patients have, in this respect, a worse prognosis than responders after resection. The prediction of responding patients to neoadjuvant therapy as well as the early identification of patients who will not respond is of utmost clinical importance. Today, there is no absolute evidence that neoadjuvant treatment for patients with potentially resectable Barrett's cancer prolongs survival. In patients with locally advanced, presumably not completely resectable adenocarcinoma of the esophagus, preoperative treatment appears to increase the chance for a curative resection and enhance survival in responding patients. Neoadjuvant treatment of adenocarcinoma of the esophagus, as a consequence, is currently not the standard treatment and should be performed only within controlled clinical trials.

Endoscopic ultrasound and upper gastrointestinal disorders

Endoscopic ultrasound (EUS) plays a vital role in management of upper gastrointestinal disorders, particularly cancer of the esophagus, pancreas, stomach, lung (via transesophageal mediastinal staging), and bile duct. Endoscopic ultrasound has also been valuable in detection of early chronic pancreatitis (CP). In cancer of the esophagus, the primary role of EUS is to determine whether disease is localized (T1-2, N0) and appropriate for surgery, locally advanced (T3-4, N1, M1a) (which may benefit from chemoradiation with or without surgery), or metastatic. Pancreatic and bile duct cancers are more complex given the controversy over portal vein resection. In centers that resect tumors invading the portal venous system, the role of EUS is limited to tissue confirmation or identification of metastases to the liver or distant lymph nodes. In centers that do not resect the portal vein invasion, EUS plays an important role in local staging. In lung cancer, EUS is emerging as an accurate, nonsurgical alternative to staging the mediastinum through EUS fine-needle aspiration. Endoscopic ultrasound has an important role in diagnosing CP because of its high degree of sensitivity. This has also led to controversy over whether EUS can overdiagnose CP. For these reasons, we recommend the use of a high threshold for EUS and that CP be diagnosed in conjunction with other standard tests (endoscopic retrograde cholangiopancreatography, pancreatic function tests).

Usefulness of positron emission tomography for assessing the response of neoadjuvant chemoradiotherapy in patients with esophageal cancer

BACKGROUND

In this study, we retrospectively assessed the performance of 18-F-fluorodeoxyglucose positron emission tomography (FDG-PET) compared with computed tomography (CT) and esophagography for assessing the response of advanced esophageal squamous cell carcinoma (SCC) to neoadjuvant chemoradiotherapy.

METHODS

We studied 10 patients with thoracic esophageal SCC who received neoadjuvant chemoradiotherapy followed by surgery. Tumor response was assessed by CT, endoscopy, esophagography and FDG-PET before and after neoadjuvant treatment.

RESULTS

Assessment of the rate of decrease in standardized uptake value (SUV) revealed a partial response (more than 50% decrease) in 5 (50%) of the patients, and assessment of length decrease of FDG uptake showed a partial response in 9 (90%) of the patients. Comparison of the histological response and the rate of decrease of various parameters revealed significant associations between histological response and tumor length (P <0.05), SUV after neoadjuvant therapy (P <0.05), and reduction in the extent of FDG uptake (P <0.01). However histological response was not significantly correlated with the rate of reduction of SUV, for both CT and esophagography.

CONCLUSIONS

FDG-PET may be of considerable value for predicting the pathologic response of esophageal SCC to neoadjuvant therapy. Despite assessment of SUV before neoadjuvant therapy, low FDG uptake after therapy and reduction in the extent of FDG uptake may provide a reliable assessment of the response to therapy.

New techniques for staging esophageal cancer

Correct staging is essential for treatment selection, discussion of prognosis, and scientific communication. The CT scan has long been the essential tool for staging esophageal cancer and still remains valuable for initial screening for distant metastases. The development of endoscopic ultrasonography (EUS), with EUS fine-needle aspiration, positron emission tomography, and minimally invasive surgical staging via thoracoscopy and laparoscopy has resulted in more precise staging. These new tools will allow better definition of patient subsets that may benefit from selected therapies and clinical investigations.

Helical CT versus EUS with fine needle aspiration for celiac nodal assessment in patients with esophageal cancer

BACKGROUND

Conventional CT is insensitive for detection of metastatic involvement of celiac lymph nodes in esophageal cancer. Helical CT has theoretical advantages over "slice" CT in this regard, but its performance has not yet been prospectively studied.

METHODS

Consecutive patients with untreated esophageal cancer were recruited after obtaining informed consent. Helical CT was performed on all patients and TNM staging was performed by a single radiologist. Subsequently, all patients underwent esophageal radial and, as needed, curvilinear array EUS with fine needle aspiration (FNA), for evaluation of celiac lymph nodes and TNM staging. Test performance characteristics with 95% confidence intervals were calculated, assuming EUS with FNA as the reference standard.

RESULTS

Forty-eight patients were recruited, of whom 37 (77%) were men. The mean (SD) age was 63.6 (10) years. Excluding 5 patients in whom a confirmatory FNA was not available (n = 43), helical CT identified celiac lymph nodes in 12 (28%) patients. The reference standard of EUS with FNA identified 15 (35%) patients with metastatic celiac lymph nodes, giving a sensitivity, specificity, and positive and negative predictive values for helical CT of 53% (95% CI [28%, 79%]), 86% (95% CI [73%, 99%]), 67% (95% CI [40%, 93%]), and 77% (95% CI [63%, 92%]), respectively, for assessing celiac lymph nodal involvement. The sensitivity and specificity of helical CT in detecting T4 disease were 25% (95% CI [3.8%, 46%]) and 94% (95% CI [85%, 100%]), respectively. There were 12 patients (25%; 95% CI [13%, 37%]) who were felt to have resectable disease by helical CT but had either metastatic involvement of celiac lymph nodes or T4 disease by EUS/FNA.

CONCLUSIONS

Despite technological advances, helical CT still appears unreliable, mainly because of insensitivity, for the identification of inoperable T4 or metastatic involvement of celiac lymph node disease in esophageal cancer.

Correlation of EUS measurement with pathologic assessment of neoadjuvant therapy response in esophageal carcinoma

BACKGROUND

EUS-measured reduction in tumor size after neoadjuvant therapy has previously been correlated with downstaging and improved survival in patients with esophageal cancer. The aim of this study was to determine whether tumor changes measured by EUS correspond to pathologically assessed chemoradiotherapy-induced tumor regression.

METHODS

Forty-one patients with esophageal cancer treated with combined modality treatment were studied. After initial EUS, patients completed a cisplatin/carboplatinum, 5-fluorouracil, and radiotherapy regimen and underwent repeat EUS before resection. A positive response on EUS was defined as a 50% reduction in maximal tumor cross-sectional area. Chemoradiotherapy-induced tumor regression was assessed in resection specimens by using a previously defined pathologic scoring system based on the extent of tumor proliferation into adjacent fibrosis.

RESULTS

Pathologic tumor regression was present in 23, indeterminate in 5, and minimal or absent in 13 patients. EUS measured a positive response in 20 of 23 (87%) patients with CRT-induced tumor regression and a negative response in 10 of 13 (77%) patients with absent tumor regression (p < 0.001). EUS had a positive predictive value of 80% for pathologic tumor regression.

CONCLUSIONS

Measurement of tumor size by EUS is a reliable clinical method for assessing pathologic tumor regression before surgery.

The use of chemoradiotherapy in oesophageal cancer

The results of treatment for oesophageal carcinoma remain poor and few patients are curable by surgery alone. The use of chemoradiotherapy (CRT) given as a definitive treatment or in combination with surgery may improve locoregional control and survival, when compared with radiotherapy or surgery alone. Using the keywords "chemoradiotherapy" and "radiochemotherapy", a Medline-based literature review (1980-2001) was performed. Additional literature was obtained from original papers and published meeting abstracts. Two-year survival rates of 28-72% in squamous cell carcinoma and 14-29% in adenocarcinoma from definitive CRT were reported. This is comparable to results achievable by surgery alone. The use of preoperative CRT followed by surgery may further improve survival, but current data are insufficient to justify this approach within routine clinical practice. Acute treatment-related toxicity is increased with CRT. In selected patients with localised unresectable oesophageal cancer, definitive CRT is recommended. There are uncertainties about the role of routine surgery following CRT in patients with resectable disease. For the future, the pretreatment staging of patients needs to be improved and standardised, the optimal CRT regimen needs to be defined and the role of predictive markers for CRT response needs to be developed.

Esophageal cancer

Accurate pretherapy staging for esophageal cancer is important for stage-directed therapy. Precise staging is also essential for quality control and ensuring the validity of clinical trials. Endoscopic ultrasound is currently the best technique in local regional staging. Various investigators have attempted to overcome the problems of nontraversable lesions and restaging after neoadjuvant therapy. Positron emission tomography scan was shown to be especially useful in identifying distant metastases. Its more widespread use is likely to impact on treatment strategies. Surgical resection remains the mainstay of treatment of esophageal cancer. Improvement in immediate postoperative morbidity, mortality, and long-term survival was shown by various reports to relate to experience and volume. The concept of three-field dissection was further defined by illustrating the importance of lymphadenectomy around the recurrent laryngeal nerves. Multimodality treatments continue to receive attention. Several studies have established the patterns of practice in the United States in treating esophageal cancer. Chemoradiation programs are gaining a more important role and are widely used, although their exact roles are uncertain. Closely related to this area of research is the search of molecular markers of favorable response to such therapies. Concerning palliative treatment for esophageal cancer, self-expanding metallic stents have a definite role in patients with malignant dysphagia. Their results and complications are reviewed. Lastly, quality-of-life issues have assumed more importance in studies in oncology. Prospective quality-of-life data should be evaluated in future studies on different treatment methods for this deadly disease.

Prediction of response to preoperative chemotherapy in adenocarcinomas of the esophagogastric junction by metabolic imaging

PURPOSE

Preoperative chemotherapy in patients with gastroesophageal cancer is hampered by the lack of reliable predictors of tumor response. This study evaluates whether positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) may predict response early in the course of therapy.

PATIENTS AND METHODS

Forty consecutive patients with locally advanced adenocarcinomas of the esophagogastric junction were studied by FDG-PET at baseline and 14 days after initiation of cisplatin-based polychemotherapy. Clinical response (reduction of tumor length and wall thickness by > 50%) was evaluated after 3 months of therapy using endoscopy and standard imaging techniques. Patients with potentially resectable tumors underwent surgery, and tumor regression was assessed histopathologically.

RESULTS

The reduction of tumor FDG uptake (mean +/- 1 SD) after 14 days of therapy was significantly different between responding (-54% +/- 17%) and nonresponding tumors (-15% +/- 21%). Optimal differentiation was achieved by a cutoff value of 35% reduction of initial FDG uptake. Applying this cutoff value as a criterion for a metabolic response predicted clinical response with a sensitivity and specificity of 93% (14 of 15 patients) and 95% (21 of 22), respectively. Histopathologically complete or subtotal tumor regression was achieved in 53% (eight of 15) of the patients with a metabolic response but only in 5% (one of 22) of the patients without a metabolic response. Patients without a metabolic response were also characterized by significantly shorter time to progression/recurrence (P =.01) and shorter overall survival (P =.04).

CONCLUSION

PET imaging may differentiate responding and nonresponding tumors early in the course of therapy. By avoiding ineffective and potentially harmful treatment, this may markedly facilitate the use of preoperative therapy, especially in patients with potentially resectable tumors.

EUS in patients with benign and malignant lymphadenopathy

BACKGROUND

The EUS appearance of lymph nodes in patients undergoing evaluation for malignancy was studied.

METHODS

In 378 patients EUS characteristics were assessed: size of tumor, largest lymph node size, number of lymph nodes, distance of lymph nodes from the tumor, and on a 5-point visual analogue scale (1 = least malignant to 5 = most malignant), roundness, homogeneity, and echogenicity. A morphology score (sum of roundness, homogeneity, and echogenicity) was calculated. Findings were compared with fine needle aspiration or surgical histopathology in 238 patients.

RESULTS

When using multivariate analysis, only lymph node size (1.4 +/- 0.1 cm vs. 1.7 +/- 0.1 cm, p = 0.001), distance from tumor (3.1 +/- 0.4 cm vs. 1.6 +/- 0.4 cm, p = 0.013), and morphology score (9.9 +/- 0.3 vs. 11.9 +/- 0.3, p = 0.001) for benign versus malignant lymph nodes (mean +/- SEM) were significant. Lymph node size was significant for esophageal cancer (p = 0.006) and other mediastinal lymph nodes (p = 0.007) but not for pancreaticobiliary malignancies (p = 0.1) or celiac lymph nodes (p = 0.4). Distance from the tumor was significant for pancreaticobiliary (p = 0.01) but not esophageal cancers (p = 0.7). Morphology was significant for all sites. The presence of at least one lymph node of 1 cm or greater within 1 cm of the tumor and with a morphology score of 14 or greater had a positive predictive value of 81% (prevalence = 13%). A morphology score of 6 or less had a negative predictive value of 92% (prevalence = 12%).

CONCLUSIONS

Patients with malignant adenopathy have lymph nodes that are larger, closer to the primary tumor, rounder, darker, and more homogeneous than those of patients without malignant adenopathy.

Evaluation of the histologic effect of chemoradiation therapy for squamous cell carcinomas of the esophagus by assessing morphologic features of surgical specimens

The histologic effects of chemoradiation therapy (CRT) for esophageal cancer, which determine the benefit obtained from a salvage operation, are difficult to evaluate preoperatively. We therefore investigated whether or not the morphologic features of esophageal cancer tissue after CRT can be correlated with the histologic features of the tissue. Seventy-six patients with advanced esophageal squamous cell carcinoma underwent CRT followed by esophagectomy. The effects of CRT were evaluated by histologic examination of the residual tumors in the surgical specimen and correlated with clinicopathologic factors, including postoperative prognosis. The histologic effects of CRT were used to classify tumors as grade 1 (CRT poorly effective; 23 cases, 30.3%); grade 2 (CRT moderately effective; 31 cases, 40.8%); or grade 3 (CRT completely effective with no residual tumors; 22 cases, 28.9%). Among the gross findings of the removed esophagus, significant correlation with the CRT effects was observed in the case of wall thickness and ulceration but not in the case of longitudinal tumor length. Tumors with no wall thickening or ulceration were never classified as grade 1, whereas tumors with both wall thickening and ulceration were frequently rated as grade 1 (18/30, 60%). Microscopic examination of grade 2 tumors (23/31, 74.1%) revealed residual tumor cells growing below the mucosal layer, whereas tumor cells were exposed to the esophageal surface in 22 out of 23 patients with grade 1 tumors. The morphologic features after CRT can be used to evaluate its histologic effect, especially in the case of grade 1 tumors. However, the detection and prediction of grade 2 tumors remains difficult because of the presence of small amounts of residual tumor underneath the mucosa.

Preoperative (neoadjuvant) chemoradiotherapy in oesophageal cancer

BACKGROUND

Oesophageal cancer carries a poor prognosis. The 5-year survival rate following resection ranges from 10 to 35 per cent. Recent evidence suggests that the addition of non-surgical treatments to surgery may improve resection rates, reduce the risk of recurrence and improve survival. This review examines the role of preoperative chemoradiotherapy (CRT) in oesophageal cancer.

METHODS

A Medline-based literature review (1980-2000) was performed using the key words 'neoadjuvant or preoperative' and 'chemoradiotherapy or radiochemotherapy'. Additional literature was obtained from original papers and published meeting abstracts.

RESULTS

Forty-six non-randomized and six randomized trials of preoperative CRT were found. Resection rates, pathological complete response (pCR), treatment-related mortality rates and relapse patterns are documented. Improved 5-year survival rates approaching 60 per cent may be achieved following pCR. Three of the six randomized trials show a benefit in either overall survival or disease-free survival compared with surgery alone. Treatment-related toxicity can be significant.

CONCLUSION

Preoperative CRT may improve survival. Emerging evidence suggests that CRT alone can achieve similar survival rates to surgery alone. New imaging modalities may help to select which patients require surgery. Larger randomized trials of preoperative CRT or chemotherapy are needed to define optimal regimens and produce higher pCR rates with acceptable toxicity.

Neoadjuvant therapy of esophageal squamous cell carcinoma: response evaluation by positron emission tomography

OBJECTIVE

To evaluate the use of positron emission tomography using [(18)F]-fluorodeoxyglucose (FDG-PET) to assess the response to neoadjuvant radiotherapy and chemotherapy in patients with locally advanced esophageal cancer.

SUMMARY BACKGROUND DATA

Imaging modalities, including endoscopy, endoscopic ultrasound, computed tomography, and magnetic resonance imaging, currently used to evaluate response to neoadjuvant treatment in esophageal cancer do not reliably differentiate between responders and nonresponders.

METHODS

Twenty-seven patients with histopathologically proven squamous cell carcinoma of the esophagus, located at or above the tracheal bifurcation, underwent neoadjuvant therapy consisting of external-beam radiotherapy and 5-fluorouracil as a continuous infusion. FDG-PET was performed before and 3 weeks after the end of radiotherapy and chemotherapy (before surgery). Quantitative measurements of tumor FDG uptake were correlated with histopathologic response and patient survival.

RESULTS

After neoadjuvant therapy, 24 patients underwent surgery. Histopathologic evaluation revealed less than 10% viable tumor cells in 13 patients (responders) and more than 10% viable tumor cells in 11 patients (nonresponders). In responders, FDG uptake decreased by 72% +/- 11%; in nonresponders, it decreased by only 42% +/- 22%. At a threshold of 52% decrease of FDG uptake compared with baseline, sensitivity to detect response was 100%, with a corresponding specificity of 55%. The positive and negative predictive values were 72% and 100%. Nonresponders to PET scanning had a significantly worse survival after resection than responders.

CONCLUSION

FDG-PET is a valuable tool for the noninvasive assessment of histopathologic tumor response after neoadjuvant radiotherapy and chemotherapy.

Esophageal cancer: a systematic review

Carcinoma of the esophagus has one of the lowest possibilities of cure, with 5-year survival rates estimated to be approximately 10% overall; these rates are second only to hepatobiliary and pancreatic cancers. This fact and the rapid increase in the incidence of adenocarcinomas of the esophagus in recent years challenges us to identify areas of improvement for all aspects of this disease. We discuss potential reasons for the increase in the incidence of adenocarcinomas, evidence that defines the similarity between tumors of the gastroesophageal junction and the tubular esophagus, and other prognostic factors that may influence future modifications of our staging classification of this disease. Surgical advances have translated into improvements in surgical morbidity and mortality rates. Current therapeutic options and the relative merits of the options are discussed. Improvements in patient outcome most likely hinge on earlier diagnosis, more accurate staging, and the optimal use of combined modalities, coupled with technical advances in the modalities. A systematic review approach was undertaken to evaluate the performance characteristics of newer staging tools and the value of different combined modality approaches with particular focus on the use of those approaches for patients with potentially curable disease. A similar methodologic approach was used to address the utility of the many strategies currently used in practice for the palliation of esophageal tumors, with particular focus on the relief of malignant dysphagia. Finally, a summary of published guidelines and population-based patterns of care are presented. This serves as an overview of how all of this evidence actually translates into the care we are providing. A coordinated international effort in population-based research and randomized controlled trials would be the cornerstone to future advances in this relatively uncommon but devastating disease.

Endoscopic Ultrasound Does Not Accurately Assess Pathologic Stage of Esophageal Cancer after Neoadjuvant Chemoradiotherapy

The accuracy of endoscopic ultrasound (EUS) for initial staging of esophageal cancer is widely accepted. There is, however, considerable variability in the reported accuracy of EUS for restaging of esophageal neoplasms after neoadjuvant therapy. From June 1995 through December 1999, we prospectively studied a series of 26 patients who underwent neoadjuvant treatment for esophageal cancer and were subsequently restaged by EUS before resection. Twenty-four patients had adenocarcinoma (92%), and two patients had squamous cell carcinoma (8%). EUS correctly predicted tumor stage in seven of 26 patients for an overall accuracy of 27 per cent. EUS overestimated the depth of tumor penetration in 18 patients (69%) and underestimated depth of penetration in one patient (4%). Lymph nodes were correctly staged in 15 of 26 patients for an overall accuracy of 58 per cent. Levels of sensitivity for detecting N0 and N1 disease were 44 per cent and 80 per cent respectively. Patients with a complete pathologic response were staged as T4N1 (one patient), T3N1 (three patients), T3N1 (one patient), and T2N1 (two patients). EUS cannot distinguish tumor involvement of the esophageal wall and lymph nodes from the postinflammatory changes that characterize effective neoadjuvant treatment. EUS is of limited utility in guiding clinical decision making after neoadjuvant therapy.

Endoscopic ultrasonography in patients with gastro-esophageal cancer

For patients with gastro-esophageal cancer ultrasonography (EUS) is superior to any other imaging modality in the assessment of local tumor infiltration and local lymph nodes status. EUS is especially important in the preoperative staging of patients with esophageal cancer and patients with proximal gastric cancer. Here it allows for the identification of those patients with advanced disease who are unlikely to benefit from surgery and in whom a conservative palliative treatment is indicated. In advanced gastric cancer the clinical implications of EUS less clear. Still preoperative EUS is indicated in every patient with cancer of the proximal stomach to assess tumor infiltration in the esophagus. Relatively new is the use of EUS in staging early cancers in order to select patients for local endoscopic treatment. High-frequency miniprobes are the instruments of choice for imaging these lesions. Strict criteria should be applied in the selection of patients for local endoscopic treatment of early gastro-esophageal cancers. EUS guided fine needle aspiration (EUS-FNA) is currently only indicated in patients with esophageal cancer and suspicious celiac lymph nodes. It may become more important if new treatment protocols demand more objective and reliable assessment of lymph node status.

Esophageal cancer

Carcinoma of the esophagus and gastroesophageal junction continues to be an aggressive cancer with poor prognosis, despite improved surgical results and the potential benefit of combined multimodality regimens. Additional data seem to confirm the rising incidence of adenocarcinoma, although users of nonsteroidal anti-inflammatory drugs seem to have a decreased risk. Much attention is focused on detecting high-grade dysplasia and early carcinoma with promising results using red fluorescence after preceding 5-aminolevulinic acid (ALA) sensitization. Positron emission tomography made a major breakthrough and seems to be superior to computed tomography in detecting distant metastasis as well as lymph node metastasis. Endoscopic ablation of early carcinoma results in promising early results, but a major issue remains the EUS discrimination between Tis-T1a and T1b, as the latter is frequently associated with lymph node metastasis. In the field of molecular biology, research is unraveling the role of cadherins and catenins in the mechanism underlying cell adherence, cell movement, and progress toward tumor formation. Mutations of p53 are correlated with loss of apoptosis and form an early step in progress toward carcinoma as well as mutations of other tumor-suppressing genes (eg, p16 and Rb mutations). Detection of such mutations may become useful prognostic indicators, but illustrate the genetic polymorphism influencing the susceptibility to carcinoma. Several lines of evidence suggest that the stabilizing or overriding of p53 mutant cancer cells and restoration of the wild-type tumor suppressor gene p53 may improve results of DNA damaging treatment modalities. Further research in this field may lead to new forms of anticancer therapy.

Endoscopic ultrasound cannot determine suitability for esophagectomy after aggressive chemoradiotherapy for esophageal cancer

OBJECTIVE

Endoscopic ultrasound (EUS) provides important information in the initial staging of patients with esophageal cancer. With recent modifications in chemoradiotherapy protocols, a significant number of patients have no residual tumor at esophagectomy. The high surgical morbidity and mortality might be avoided if complete response to chemoradiotherapy could be predicted. Previously published clinical trials, with relatively small patient numbers, have suggested that EUS may accurately stage esophageal cancer after chemoradiotherapy. The aim of this study was to verify the accuracy of EUS in staging esophageal cancer after effective chemoradiotherapy.

METHODS

EUS staging was performed before and after concurrent cisplatin, 5-fluorouracil, and hyperfractionated radiotherapy in 59 patients with newly diagnosed esophageal cancer. All patients underwent subsequent esophagectomy and pathological staging. The accuracy of preoperative, postchemoradiotherapy EUS was evaluated in a retrospective fashion by comparison to pathological staging.

RESULTS

After chemoradiotherapy, 18 patients (31%) had no residual disease at pathological staging (T0N0). However, EUS correctly predicted complete response to chemoradiotherapy (T0N0) in only three patients (17%). The accuracy of postchemoradiotherapy EUS for pathological T stage was only 37%, and its sensitivity for N1 disease was only 38%. EUS was unable to distinguish postradiation fibrosis and inflammation from residual tumor.

CONCLUSION

When aggressive preoperative chemoradiotherapy is provided to patients with esophageal cancer, the predictive value of postchemoradiotherapy EUS is inadequate for use in clinical decision making.