The accuracy of endoscopic ultrasonography with fine-needle aspiration, integrated positron emission tomography with computed tomography, and computed tomography in restaging patients with esophageal cancer after neoadjuvant chemoradiotherapy

Induction chemotherapy followed by surgery for advanced oesophageal cancer

BACKGROUND

Patients with locoregionally advanced oesophageal tumours or disputable distant metastases are referred for induction chemotherapy with the aim to downstage the tumour before an oesophagectomy is considered.

STUDY DESIGN

Patients who underwent induction chemotherapy between January 2005 and December 2012 were identified from an institutional database. Treatment plan was discussed in the multidisciplinary team. Response to chemotherapy was assessed by CT. Survival was calculated using the Kaplan Meier method. Uni- and multivariable analyses were performed to identify prognostic factors for survival.

RESULTS

In total 124 patients received induction chemotherapy mainly for locoregionally advanced disease (n = 80). Surgery was withheld in 35 patients because of progressive disease (n = 16) and persistent unresectability (n = 19). The median overall survival of this group was 13 months (IQR: 8-19). The remaining 89 patients underwent surgery of which 13 still had unresectable tumour or distant metastases. Of the 76 patients that underwent an oesophagectomy, 50 patients had tumour free resection margins (66%) with an estimated 5-year survival of 37%. A positive resection margin (HR 4.148, 95% CI 2.298-7.488, p < 0.0001) was associated with a worse survival in univariable analysis, but only pathological lymph node status with increasing hazard ratio's (6.283-10.283, p = 0.001) remained significant after multivariable analysis.

CONCLUSION

Induction chemotherapy downstages the tumour and facilitates a radical oesophagectomy in patients with advanced oesophageal cancer. Pathological lymph node status is an independent prognostic factor for overall survival.

Value of CT–PET after neoadjuvant chemoradiation in the prediction of histological tumour regression, nodal status and survival in oesophageal adenocarcinoma

Background

The role of CT–PET after neoadjuvant chemoradiation (nCRT) for prediction of pathological response and oncological outcome in oesophageal and junctional adenocarcinoma (OAC) is unclear. The relationship between complete metabolic response (cMR), pathological complete response (pCR) and nodal status has not been clarified.

Methods

Patients with locally advanced OAC selected to receive nCRT and surgery with curative intent, on the basis of staging that included CT–PET positivity, were included. Repeat scanning (PET2) with an identical protocol was performed 2–4 weeks after completion of nCRT (cisplatin and 5-fluorouracil plus 44 Gy radiation). Changes in [18F]fluorodeoxyglucose uptake, considered as either a maximum standardized uptake value (SUVmax) or a relative reduction (%ΔSUVmax), and PET-predicted nodal status following nCRT were compared with histopathological response, histological node positivity and survival.

Results

One hundred consecutive patients with PET-positive OAC were studied. Following nCRT, PET2 identified M1 disease in 2·0 per cent of patients. There were no significant associations between PET2 SUVmax or %ΔSUVmax with respect to primary tumour stage (ypT) (P = 0.216 and P = 0·975 respectively), tumour regression grade (P = 0·109 and P = 0·232), pCR (P = 0·633 and P = 0·870) or complete resection (R0) (P = 0·440 and P = 0·235). The sensitivity of PET2 for ypN was 10 per cent. %ΔSUVmax was not associated with disease-free or overall survival (P = 0·162 and P = 0·154 respectively). Of 46 patients with a cMR on PET2, 37 (80 per cent) had histological evidence of residual tumour in the resected specimen, and cMR was not associated with overall survival benefit (P = 0·478).

Conclusion

CT–PET following nCRT for OAC has poor prognostic and discriminatory value for clinical application.

Evaluation of progression prior to surgery after neoadjuvant chemoradiotherapy with computed tomography in esophageal cancer patients

BACKGROUND

The risk of tumor progression during neoadjuvant chemoradiotherapy (CRT) in esophageal cancer (EC) is around 8% to 17%. We assessed the efficacy of computed tomography (CT) to identify these patients before esophagectomy.

METHODS

Ninety-seven patients with locally advanced EC treated with Carboplatin/Paclitaxel and 41.4 Gy neoadjuvantly were restaged with CT. Two radiologists reviewed pre- and post-CRT CT images. The primary outcome was detection of clinically relevant progressive disease. Missed metastases were defined as metastatic disease found during surgery or within 3 months after post-CRT CT.

RESULTS

Progressive disease was detected in 9 patients (9%). Both radiologists detected 5 patients with distant metastases (liver, n = 4; lung metastasis, n = 1), but missed progressive disease in 4 cases. One radiologist falsely assessed 2 metastatic lesions, but after agreement progressive disease was detected with sensitivity and specificity of 56% and 100%, respectively.

CONCLUSION

CT is effective in detecting clinically relevant progressive disease in EC patients, after neoadjuvant treatment.

Feasibility of endoscopic mucosal resection as salvage treatment for patients with local failure after definitive chemoradiotherapy for stage IB, II, and III esophageal squamous cell cancer

Local failure after definitive chemoradiotherapy (CRT) for stage IB, II, and III esophageal cancer is one of the causes of poor outcome. Endoscopic mucosal resection (EMR) is an effective treatment for superficial esophageal cancer. However, its feasibility as a salvage treatment for local recurrent or residual tumors after definitive CRT for stage IB, II, and III esophageal cancer remains unclear. Between January 2000 and February 2008, 274 patients with stage IB, II, and III esophageal squamous cell cancer excluding T4 received definitive CRT at the National Cancer Center Hospital, Japan. Of these patients, nine patients with local recurrence after achieving complete response and two patients with residual tumor underwent salvage EMR. The technique of salvage EMR involved a strip biopsy method. We retrospectively reviewed the 11 patients (13 lesions). Characteristics of all 11 patients were as follows: median age of 69 (range: 45-78); male/female: 10/1; baseline clinical stage (Union for International Cancer Control 7th) IB/IIA/IIB/III: 1/3/7/0. The depth of resected tumor was limited to the mucosal layer in seven lesions and submucosal in six lesions. En bloc resection was performed on six lesions (46%). The vertical margin was free of cancer cells in 11 lesions (84.6%). No major complications, such as hemorrhage requiring blood transfusion and perforation, were experienced. At a median follow-up period of 38.9 months (range: 5.3-94 months) after salvage EMR, no recurrence was detected in six patients (54%). Local recurrence was detected in five patients (27%). Of these patients, two had lung metastasis simultaneously, and one was also detected lung metastasis 2 months after the detection of local recurrence. The 5-year survival rate after salvage EMR was 41.6%. Salvage EMR is a feasible treatment option for local recurrent or residual lesions after definitive chemotherapy and/or radiotherapy for stage IB, II, and III esophageal squamous cell cancer.

Radiographic and endosonographic staging in esophageal cancer

Radiographic imaging using computed tomographic (CT) scan and positron emission tomography/CT are primarily helpful in identifying distant metastases. In general, if patients have evidence of lymph node involvement that is proved pathologically by endoscopic ultrasound/fine needle aspiration, this information is considered definitive, and the patient can be referred for the appropriate stage-specific therapy. Laparoscopy combined with laparoscopic ultrasound and peritoneal lavage has been shown to have sensitivity of 67% and specificity of 92% for lymph node disease. Thoracoscopy may help identify involved lymph node in the mediastinum before resection and help determine the field of radiation.

Endoscopic management of esophageal cancer after definitive chemoradiotherapy

BACKGROUND

Concurrent chemoradiotherapy (CRT) is a potentially curative non-surgical option for locally advanced esophageal cancer, with pathological complete response (CR) ranging from 13 to 49 %. The rate of persistent and recurrent disease within the esophagus remains high at 40-60 %, and treatment of these tumors may improve disease-free survival. The aim of this review is to assess the efficacy of salvage endoscopic therapies for recurrent esophageal cancer.

METHODS

Medline and Embase were searched for relevant studies published in the English-language literature that reported use of endoscopic modalities, including photodynamic therapy (PDT), endoscopic mucosal resection (EMR), and spray cryotherapy, as salvage therapies for esophageal cancer.

RESULTS

A total of 12 studies were identified. In small case series of PDT, CR varied from 20 to 100 %, with 1-, 3-, and 5-year overall survival rates of 65-80, 34-47, and 36 %, respectively. Data from three studies of EMR in squamous cell cancer show CR in 50 % of cases, with 3- and 5-year overall survival of 56-81 and 49 %, respectively. Endoscopic spray cryotherapy has recently been used in this setting with an observed CR of 37.5 %.

CONCLUSIONS

Endoscopic salvage therapies are options for those patients with disease limited to the superficial esophageal wall and those who are unfit to undergo salvage esophagectomy. Widespread application of endoscopic salvage therapies is limited by the lack of awareness and guidelines for endoscopic surveillance post-CRT and limited data on the effectiveness of endoscopic therapies.

Accuracy of multidetector-row CT for restaging after neoadjuvant treatment in patients with oesophageal cancer

OBJECTIVES

To assess the diagnostic accuracy of 64-multidetector CT (MDCT) for restaging of patients with oesophageal cancer undergoing neoadjuvant therapy.

METHODS

Results of pathological staging were correlated with those from 64-MDCT before and after neoadjuvant treatment in 35 patients using the American Joint Committee on Cancer/TNM classification (7th edition). CT response was determined using the Response Evaluation Criteria in Solid Tumours (RECIST) method, modified for one-dimensional tumour diameter measurement.

RESULTS

64-MDCT predicted T stage correctly in 34 % (12/35), overstaged in 49 % (17/35) and understaged in 17 % (6/35). Sensitivity/specificity values were as follows: T0, 20 %/92 %; T1-T2, 31 %/59 %; T3, 60 %/64 %; T4, 100 %/4 %. Negative predictive values for T3/T4 were 80 %/100 %. MDCT accurately predicted complete histopathological response in 20 % (accuracy 74 %) and overstaged in 80 %. Tumour regression grade was predicted correctly in only 8 % (2/25) and underestimated in 68 % (17/25). Accurate N stage was noted in 69 % (24/35).

CONCLUSION

Although MDCT tends to be able to exclude advanced tumour stages (T3, T4) with a higher likelihood, the diagnostic accuracy of high resolution MDCT for restaging oesophageal cancer and assessing the response to neoadjuvant therapy has not improved in comparison to older-generation CT. Therefore, the future assessment of oesophageal tumour response should focus on combined morphologic and metabolic imaging.

KEY POINTS

• Multidetector CT (MDCT) has been beneficial for the evaluation of many tumours. • However diagnostic accuracy for restaging oesophageal cancer has not improved with MDCT. • MDCT tends to be able to exclude advanced tumour stages (T3/T4). • MDCT has a low accuracy for determining lymph node metastasis. • Oesophageal tumour response should be assessed by combined morphological and metabolic imaging.

Oesophageal cancer--an overview

Oesophageal carcinoma is one of the most virulent malignant diseases and a major cause of cancer-related deaths worldwide. Diagnosis and accuracy of pretreatment staging have substantially improved throughout the past three decades. Therapy is challenging and the optimal approach is still debated. Oesophagectomy is considered to be the procedure of choice in patients with operable oesophageal cancer. Endoscopic measures and limited surgical procedures provide an alternative in patients with early carcinomas confined to the oesophageal mucosa. Chemotherapy and radiotherapy or concurrent chemoradiotherapy are also frequently applied, either as definitive treatment or as neoadjuvant therapy within multimodal approaches. The question of whether multimodal treatment offers improved results has been the focus of many studies since the 1990s. Although results are discordant and even some meta-analyses remain inconclusive, it is now widely accepted that multimodal therapy leads to a modest survival benefit. The role of minimally invasive oesophagectomy is not yet defined. Endoscopic stent insertion, radiotherapy and other palliative measures provide relief of tumour-related symptoms in advanced, unresectable tumour stages.

Endoscopic ultrasound fine needle aspiration: Technique and applications in clinical practice

Since its initial report in 1992, endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has now been incorporated into the diagnostic and staging algorithm for the evaluation of benign and malignant diseases of the gastrointestinal tract and of adjacent organs. Its introduction constitutes a major breakthrough in the endoscopic field and has gradually transformed EUS from a pure imaging modality into a more interventional. In addition, the possibility of collecting samples, providing a definitive cytological and/or histological evidence of the presence of malignancy, has strongly contributed to changing EUS from a subjective, highly operator dependant procedure into a more objective one. This article will review the instrumentation, technique and the most important clinical applications of EUS-FNA.

Definitive chemoradiotherapy for esophageal carcinoma

Radiation therapy plays an important role in the treatment of esophageal cancer. Radiation therapy may be combined with chemotherapy, used as a component of induction therapy, used in the adjuvant setting, or used for palliation of advanced disease. Chemotherapy is also occasionally used as a solitary treatment modality for patients with esophageal cancer. Current treatment protocols include multiple agents, and agents directed against specific molecular targets have been investigated in clinical trials. This article discusses future directions related to the selection of radiation treatment protocols, novel targeted chemotherapeutic agents, and the selection of patients for surgery.

Oesophageal tumour progression between the diagnostic ¹⁸F-FDG-PET and the ¹⁸F-FDG-PET for radiotherapy treatment planning

BACKGROUND AND PURPOSE

To test whether the interval between diagnostic and therapeutic FDG-PET-scanning is associated with early tumour progression.

MATERIAL AND METHODS

All patients (n=45) underwent two PET scans, one for staging ('baseline PET') using an HR+ positron camera or PET/CT-scanner and one for radiotherapy planning ('therapeutic PET') using a PET/CT-scanner. All images were reviewed in random order by an experienced nuclear physician. If there were any discrepancies, the images were also compared directly. SUVmax, tumour length, lymph node metastases and distant metastases were assessed.

RESULTS

The median time between the PET scans was 22 days (range: 8-49). The SUVmax increased (>10%) (19 patients, 42%) or decreased (11 patients, 24%). Fourteen patients (31%) showed tumour length progression (>1cm). TNM progression was found in 12 patients (27%), with newly detected mediastinal nodes (N) in eight patients (18%) and newly detected distant metastases (M) in six patients (13%). No significant prognostic factors were found. However, a trend was noted towards TNM progression for the type of PET-camera (p=0.05, 95% CI 0.01-0.66) and for the interval between the PET scans (p=0.09, 95% CI -0.9 to 12.5).

CONCLUSION

This study suggests rapid oesophageal tumour progression. Therefore, the interval between relevant imaging and start of the radiotherapy should be minimized. Furthermore, 'state of the art' PET scanners should be used.

Quantitative measurement of contrast enhancement of esophageal squamous cell carcinoma on clinical MDCT

AIM

To investigate contrast-enhanced computed tomography (CECT) for discriminating esophageal squamous cell carcinoma (ESCC) from normal esophagus and evaluating outcomes within tumors after chemoradiotherapy (CRT).

METHODS

Sixty-four patients with surgical ESCC served as group A, and underwent thoracic contrast-enhanced scan with 16-section multidetector row CT 1 wk before surgery. Thirty-five patients with advanced ESCC receiving 4-wk CRT and showing response to CRT served as group B, and underwent CT scans similar with group A 4 wk after completion of CRT. In group A, differences in CT attenuation values (in HU) between the preoperative ESCC and background normal esophageal wall (delta CT(1)), or between different background normal esophageal walls (delta CT(2)) were compared. Furthermore, delta CT(1) between group A and B was also compared.

RESULTS

In group A, mean delta CT(1) was higher than delta CT(2) (23.86 ± 10.59 HU vs 6.24 ± 3.06 HU, P < 0.05). When a delta CT(1) of 10.025 HU was employed at a cut-off value to discriminate ESCC from normal esophagus, a sensitivity of 89.1% and specificity of 90.6% were achieved. Mean delta CT(1) was lower in group B than in group A (9.25 ± 10.86 vs 23.86 ± 10.59, P < 0.05), and a delta CT(1) of 15.45 HU was obtained at a cut-off value to assess the CRT changes with a sensitivity of 76.6% and specificity of 77.1%.

CONCLUSION

CECT might be a clinical technique for discriminating ESCC from normal esophagus, and evaluating outcome in the tumors treated with CRT.

PET staging of mediastinal lymph nodes in thoracic oncology

There is an extensive and growing body of literature about the role of positron emission tomography (PET) in the management of non-small cell lung cancer and esophageal cancer. This article focuses on the use of PET in mediastinal staging of these common thoracic malignancies. PET is the most accurate noninvasive approach to staging mediastinal lymph nodes in non-small cell lung cancer. The role of PET in mediastinal lymph node staging in esophageal cancer is less clear, since it has been largely supplanted by endoscopic ultrasonography. A review of the evidence for and against the use of PET in mediastinal staging is provided and the use of PET in practice is discussed.

Can ¹⁸F-fluorodeoxyglucose positron emission tomography predict responses to neoadjuvant therapy in oesophageal cancer patients? A meta-analysis

OBJECTIVES

Neoadjuvant therapy for the treatment of oesophageal cancer was introduced in an effort to improve prognosis. Response assessment is crucial for the treatment of patients with oesophageal cancer. Currently, ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) seems to be the best available tool to assess neoadjuvant therapy response in patients with oesophageal cancer. The purpose of this study was to assess the diagnostic value of ¹⁸F-FDG PET for the evaluation of neoadjuvant therapy responses in patients with oesophageal cancer using a meta-analysis. A unified procedure and evaluation standard for ¹⁸F-FDG PET in the assessment of neoadjuvant therapy response should be established.

METHODS

All published English-language studies pertaining to the assessment of neoadjuvant therapy response in patients with oesophageal cancer using ¹⁸F-FDG PET in the MEDLINE and EMBASE databases were collected. The methodological quality of the included studies was evaluated according to the Quality Assessment of Diagnostic Accuracy Studies quality assessment tool. Pooled sensitivity, specificity, diagnostic odds ratios and summary receiver operating characteristic curves were obtained using statistical software.

RESULTS

Thirteen studies included in the meta-analysis fulfilled the inclusion criteria of the Quality Assessment of Diagnostic Accuracy Studies quality assessment tool. The pooled sensitivity, specificity and diagnostic odds ratios for F-¹⁸FDG PET in the evaluation of neoadjuvant therapy response in patients with oesophageal cancer were 70.3% [95% confidence interval (CI): 64.4-75.8], 70.1% (95% CI: 65.1-74.8) and 9.389 (95% CI: 3.482-25.319), respectively. The area under the curve and the Q value for the summary receiver operating characteristic curve were 0.8244 and 0.7575, respectively.

CONCLUSION

¹⁸F-FDG PET has some value in the assessment of neoadjuvant therapy response in patients with oesophageal cancer. A 50% reduction in standardized uptake value between pretherapy and posttherapy positron emission tomography scans performed in the first 2 weeks after the initiation of neoadjuvant therapy is the optimal condition for predicting a response to neoadjuvant therapy in patients with oesophageal cancer.

Comparative study between endoscopic ultrasonography and positron emission tomography-computed tomography in staging patients with esophageal squamous cell carcinoma

Treatment strategy of esophageal cancer mainly depends on accurate staging. At present, no single ideal staging modality is superior to another in preoperative tumor-node-metastasis (TNM) staging of patients with esophageal cancer. We aimed to investigate the efficacy of endoscopic ultrasonography (EUS) and positron emission tomography-computed tomography (PET-CT) for staging of esophageal cancer. We retrospectively studied 118 consecutive patients with esophageal squamous cell carcinoma who underwent esophagectomy with or without neoadjuvant chemoradiotherapy (CRT) over a near 3-year period between January 2005 and November 2008 at a tertiary hospital in Taiwan. Patients were separated into two groups: without neoadjuvant CRT (group 1, n= 28) and with CRT (group 2, n= 90). Medical records of demographic data and reports of EUS and PET-CT of patients before surgery were reviewed. A database of clinical staging by EUS and PET-CT was compared with one of pathological staging. The accuracies of T staging by EUS in groups 1 and 2 were 85.2% and 34.9%. The accuracies of N staging by EUS in groups 1 and 2 were 55.6% and 39.8%. The accuracies of T and N staging by means of PET-CT scan were 100% and 54.5% in group 1, and were 69.4% and 86.1% in group 2, respectively. In group 2, 38 of 90 patients (42.2%) achieved pathologic complete remission. Among them, two of 34 (5.9%) and 12 of 17 (70.6%) patients were identified as tumor-free by post-CRT EUS and PET-CT, respectively. EUS is useful for initial staging of esophageal cancer. PET-CT is a more reliable modality for monitoring treatment response and restaging. Furthermore, the accuracy of PET-CT with regard to N staging is higher in patients who have undergone CRT than those who have not.

The role of endoscopic ultrasound in assessing tumor response and staging after neoadjuvant chemotherapy for esophageal cancer

BACKGROUND

Although the role of endoscopic ultrasound (EUS) in the initial staging of esophageal cancer is well established, its role in assessing tumor response and staging esophageal cancers after neoadjuvant chemotherapy (NAC) is controversial, and this study aimed to investigate this role.

METHODS

This study retrospectively analyzed 110 patients with esophageal cancer who underwent EUS by single surgeon before and after NAC. Tumor response was assessed before and after NAC. Patients with more than a 50% reduction in tumor size based on EUS evaluation were classified as having a significant response to chemotherapy, and those with less than a 50% reduction were categorized as having a partial response. Disease stage was established by tumor node metastasis (TNM) classification. Initial staging was performed using EUS and computed tomography (CT) scans of the chest and abdomen. The EUS-determined stage was compared with the postsurgical pathologic stage. χ(2) analysis and Fisher's exact testing were performed.

RESULTS

A response to NAC was shown by 96 patients (87.3%) and no response by 14 patients (12.7%). Of the 96 responding patients, 37 (38.5%) showed a significant response, whereas 43 (61.5%) of 69 patients showed a partial response. The EUS staging correlated well with the pathologic staging for 9 (64.3%) of the 14 nonresponders and for 34 (35.4%) of the 96 responders to NAC (P = 0.04). The EUS accurately predicted both the T and N status for 26 (23.6%) of the 110 patients. Prediction of N status was significantly more accurate than prediction of the T stage for the post-NAC patients. Of the 110 patients, 43 (39.1%) patients had an accurate T-stage prediction, and 64 (58.2%) had an accurate N stage match (P = 0.02). The T stage was overstaged for 60 (54.5%) of the patients and understaged for 7 of the patients (6.4%).The study found overstaging of the T stage to be more common among the patients who responded to chemotherapy. The N stage was overstaged for 25 (22.7%) and understaged for 21 (19.1%) of the 110 patients.

CONCLUSION

The findings showed EUS to be a useful tool for assessing response to chemotherapy and for evaluating the extent of disease, thus facilitating surgical decision making. However, EUS is an unreliable tool for staging esophageal cancer after NAC. Overstaging of the T stage is significantly more common and could be related to the inflammatory effect or fibrosis after NAC.

Clinical usefulness of dual-time FDG PET-CT in assessment of esophageal squamous cell carcinoma

PURPOSE

We conducted this study to investigate the value of the dual-time 2-[(18)F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography-computed tomography (PET-CT) in assessment of the primary tumor, loco-regional lymph node and distant metastasis in patients with esophageal squamous cell carcinoma.

METHODS

Twenty-six patients with histologically proved esophageal squamous cell carcinoma underwent dual-time FDG PET-CT before radical surgery. The standardized uptake values (SUV(max)) were obtained including early SUV(max) and delayed SUV(max), respectively. The retention index (RI) was also calculated. The results were evaluated retrospectively according to the final pathologic findings. Four diagnostic criteria including (1) early SUV(max)≧ 2.5 alone, (2) RI ≧ 10% alone, (3) a combination of early SUV(max)≧ 2.5 and RI ≧ 10%, and (4) a combination of early SUV(max)≧ 2.5 or RI ≧ 10% were used for differentiating malignancy from a benign lesion, respectively.

RESULTS

The sensitivity of FDG PET-CT in detecting the primary tumor with combination of early SUV(max)≧ 2.5 or RI ≧ 10% was 96.2%. It was statistically significantly higher than the results using the other three criteria (p<0.0001). For loco-regional lymph node detection, there was no significant difference among the 4 criteria. For distal metastases, the significantly higher specificity (100%) was found when using combination of early SUV(max)≧ 2.5 and RI ≧ 10% or using early SUV(max)≧ 2.5 alone than using the other two criteria (p=0.0058). With regard to accuracy, no significant correlations were observed among primary tumor, loco-regional lymph nodes and distant metastasis (p>0.05).

CONCLUSION

The preliminary result of this study demonstrated that dual-time point FDG PET-CT had limited value in detection of primary tumor and loco-regional lymph nodes metastasis. For the distant metastasis, the sensitivity and specificity would be improved if RI ≧ 10% is used as a supplemental criterion. Efforts should be made to improve the ability of the dual-time FDG PET-CT technique to assess primary tumor and loco-regional lymph nodes metastasis.

Staging Accuracy of Endoscopic Ultrasound Based on Pathologic Analysis after Minimally Invasive Esophagectomy

Endoscopic ultrasonography (EUS) is a common staging modality used in patients with esophageal cancer. The objective of this analysis was to evaluate the accuracy and sensitivity of EUS in determining the depth of penetration (T stage) and nodal status (N stage) in patients with esophageal cancer who underwent minimally invasive esophagectomy (MIE). A retrospective analysis of all patients at a university hospital who underwent preoperative EUS followed by MIE for cancer was performed. We compared the results of preoperative EUS to final pathologic analyses of the esophageal specimen, examining the accuracy of EUS staging. Ninety-five patients with esophageal cancer who underwent MIE had preoperative EUS. Twenty-four of the 95 patients were excluded for lack of a repeat EUS after neoadjuvant therapy before resection. Hence, 71 patients were evaluated for the accuracy of EUS staging. The accuracy of EUS for TO disease was 80 per cent; T1 disease was 75 per cent; T2 disease was 39 per cent; and T3 disease was 88 per cent. The overall EUS accuracy for T stage was 72 per cent with overstaging occurring mostly for pathologic T1 tumors in 18 per cent and understaging occurring mostly for pathologic T3 tumors in 11 per cent. The sensitivity and specificity for detection of nodal involvement were 79 per cent and 74 per cent, respectively. However the accuracy for T and N staging by EUS after neoadjuvant therapy decreased to 63 per cent and 38 per cent, respectively. Endoscopic ultrasound in the absence of neoadjuvant therapy is a relatively accurate and sensitive modality for determining the depth of tumor penetration and the presence of nodal disease in patients with esophageal carcinoma. The accuracy for T and N staging is less reliable after neoadjuvant therapy.

Metabolic response evaluation by PET during neoadjuvant treatment for adenocarcinoma of the esophagus and esophagogastric junction

Following several randomized trials, neoadjuvant therapy in adenocarcinoma of esophagus and the esophagogastric junction can be seen as an international standard. However, in a large proportion of patients the objective response achieved is unsatisfactory. These patients do not benefit from neoadjuvant therapy, but do suffer from toxic side effects; sometimes progressive and appropriate surgical therapy is delayed. For this reason, a diagnostic test that can accurately assess tumor response to neoadjuvant therapy might be of crucial importance. Response evaluation using CT scan, endoluminal ultrasound, or rebiopsy is not reliable. In recent times, response evaluation using 18FGD PET after and during neoadjuvant treatment is in the focus of clinical and scientific interest. Most studies have evaluated the diagnostic modalities for response to neoadjuvant treatment after completion of the treatment. Following the published data so far, FDG-PET seems to be less accurate after and during chemoradiation than after chemotherapy alone. The data of early response evaluation (14 days after the onset of chemotherapy) are very much encouraging; however, they have to be evaluated in an international randomized trial. Standardization of PET technology as well as defining the thresholds used for the estimation of early response is mandatory. So far, FDG-PET does not change treatment in esophageal and gastric cancer.

18-Fluorodeoxyglucose positron emission tomography as a tool for response prediction in solid tumours

Current response guidelines for the treatment of solid tumours are based on CT criteria. Over the last decades new techniques have emerged to evaluate cancer therapy. FDG-PET scanning is a more functional imaging technique, which can measure differences in metabolic activity. Although it has a low specificity, studies show that it can outperform classical CT scanning criteria. Especially in lung, breast and oesophageal cancer it can predict response earlier in the neo-adjuvant setting. This could reduce the use of ineffective cancer therapies, reducing costs and patient toxicity, and direct patients sooner towards effective therapy. The main problem with FDG-PET remains the difficulty in defining thresholds for response, as there is clearly a lack in large prospective randomized studies validating the use of FDG-PET in response guidelines.We give an overview of data on response prediction in solid tumours by the application of PET.

Endosonographic radial tumor thickness after neoadjuvant chemoradiation therapy to predict response and survival in patients with locally advanced esophageal cancer: a prospective multicenter phase ll study by the Swiss Group for Clinical Cancer Research (SAKK 75/02)

BACKGROUND

EUS response assessment in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation therapy (CRT) is limited by disintegration of the involved anatomic structures.

OBJECTIVE

Predictive and prognostic values of a prospectively defined maximum tumor thickness (MTT).

DESIGN

Prospective open-label phase ll study (SAKK 75/02).

SETTING

Multicenter, nationwide.

PATIENTS

Of 66 patients with primary CRT, 56 underwent en bloc esophagectomy.

INTERVENTIONS

EUS-measured MTT before and 2-5 weeks after CRT (yMTT).

MAIN OUTCOME MEASUREMENTS

Cutoffs: (1) absolute thickness (yMTT) after CRT < or = 6 mm; (2) relative reduction compared with baseline (ratio yMTT/MTT) < or = 50%. Correlation between EUS measurements and histopathologic tumor regression grade (TRG) and overall survival (OS).

RESULTS

Sixteen of 56 patients were not included for EUS evaluation (10 severe stenosis, 5 MTT not measured, 1 intolerance to second EUS). Characteristics (n = 40) were as follow: median age, 60 years; squamous cell carcinoma, 42%; and adenocarcinoma (AC), 58%. Initial stage was: 10 T2N1, 3 T3N0, 26 T3N1, 1 T3Nx; 14 of 23 AC Siewert type 1. Wilcoxon rank sum test showed significant correlation of TRG1 with yMTT < or = 6 mm (P = .008) and yMTT/MTT < or = 50% (P = .003). The effect of yMTT on TRG1 was significant (P = .0193; odds ratio, 0.687 [95% CI, 0.502-0.941]). The predefined cutoff of < or = 6 mm for yMTT was predictive for TRG1 (P = .0037; Fisher exact test). After a median follow-up of 28.6 months, there was a clear trend for benefit in OS with yMTT < or = 6 mm and yMTT/MTT < or = 50%.

LIMITATIONS

Small sample size.

CONCLUSION

In a multicenter setting, MTT measured by EUS after CRT was highly predictive for response and showed a clear trend for predicting survival.

Prediction of tumor response to neoadjuvant therapy in patients with esophageal cancer with use of 18F FDG PET: a systematic review

PURPOSE

To systematically review the accuracy of fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET) in the prediction of tumor response to neoadjuvant therapy in patients with esophageal cancer.

MATERIALS AND METHODS

The MEDLINE and EMBASE databases were systematically searched for relevant studies. Methodologic quality of the included studies was assessed. Sensitivities and specificities of (18)F FDG PET in individual studies were calculated and underwent meta-analysis with a random effects model. A summary receiver operating characteristic curve (sROC) was constructed with the Moses-Shapiro-Littenberg method. A chi(2) test was performed to test for heterogeneity (defined as P < .10). Potential sources for heterogeneity were explored by assessing whether certain covariates significantly (P < .05) influenced the relative diagnostic odds ratio.

RESULTS

Twenty reports, comprising a total of 849 patients with esophageal cancer, were included. Overall, the studies were of moderate methodologic quality. Sensitivity and specificity of (18)F FDG PET ranged from 33% to 100% and from 30% to 100%, respectively, with pooled estimates of 67% (95% confidence interval: 62%, 72%) and 68% (95% confidence interval: 64%, 73%), respectively. The area under the sROC curve was 0.7815. There was significant heterogeneity in both the sensitivity and specificity of the included studies (P < .0001). Spearman rho between the logit of sensitivity and the logit of 1-specificity was 0.086 (P = .719), which suggested that there was no threshold effect. Studies performed outside of the United States and studies of higher methodologic quality yielded significantly higher overall accuracy.

CONCLUSION

On the basis of current evidence, (18)F FDG PET should not yet be used in routine clinical practice to guide neoadjuvant therapy decisions in patients with esophageal cancer.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.09091324/-/DC1.

Assessment of response to neoadjuvant therapy in esophageal cancer: an updated systematic review of diagnostic accuracy of endoscopic ultrasonography and fluorodeoxyglucose positron emission tomography

For assessing response to neoadjuvant therapy in patients with esophageal cancer, both endoscopic ultrasonography (EUS) and fluorodeoxyglucose positron emission tomography (FDG-PET) are commonly used, and despite few controlled trials, it is not known if one imaging modality is superior to the other. Also, relative diagnostic accuracy of early (during the course of neoadjuvant therapy) and FDG-PET after completion of neoadjuvant therapy has not been reviewed. The aim of this study was to perform a systematic review of published information to compare diagnostic accuracy of EUS and FDG-PET in this setting. A search of the MEDLINE, EMBASE, and Cochrane databases was performed along with a manual search of cross-references of eligible articles. Data on the accuracy of the imaging modalities were compared by constructing summary receiver-operating characteristic curves. Seven studies with EUS and 15 with FDG-PET were included in the final analysis (N= 966). The sensitivity of EUS and FDG-PET ranged from 20 to 100% and 42 to 100%, respectively. The specificity ranged from 36 to 100% and 27 to 100%, respectively. The areas under the curve were 0.86 (95% confidence interval [CI]: 0.77-0.96) for EUS and 0.80 (95% CI: 0.72-0.89) for FDG PET (P= 0.37). The maximum joint sensitivity and specificity (Q* index) values for EUS and FDG-PET were 0.79 (95% CI: 0.70-0.88) and 0.74 (95% CI: 0.66-0.81), respectively (P= 0.38). There was no difference in accuracy between early FDG-PET and FDG-PET after completion of neoadjuvant therapy. EUS and FDG-PET have similar overall diagnostic accuracy for assessment of response to neoadjuvant therapy in patients with esophageal cancer.

Measurement of tumor volume by PET to evaluate prognosis in patients with head and neck cancer treated by chemo-radiation therapy

PURPOSE

To evaluate the prognostic value of the metabolic tumor volume measured on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and other clinical factors in patients treated for locally advanced head-and-neck cancer (HNC) at a single institution.

MATERIALS AND METHODS

Between June 2005 and August 2008, 59 patients with HNC that underwent pretreatment FDG-PET studies received neoadjuvant chemotherapy and radiation therapy. Metabolically active tumor regions were delineated on the pretreatment PET scans by a fixed SUV of 2.5. We evaluated the relationship of the 18F-fluorodeoxyglucose-PET maximum standardized uptake value (SUV) and the metabolic tumor volume (MTV) with the progression-free survival (PFS) and overall survival (OS).

RESULTS

The MTV and lymph node metastasis were predictive of the PFS and OS. The lymph node status did not correlate with the MTV. A higher MTV of 9.3 cm(3) was significantly associated with an increased risk of recurrence (2.19-fold, p = 0.006) and death (1.62-fold, p = 0.051). Separation of patients with tumor volumes <or= 9.3 cm(3) and no lymph node disease vs. any other combination was strongly predictive of the PFS and the OS.

CONCLUSIONS

MTV and lymph node status were prognostic values associated with survival. Quantitative measurement of tumor volume separates patients with a good prognosis from those with a poorer prognosis. A subset of patients with relatively small tumors and no lymph node involvement did very well.

Clinical utility of postchemoradiation endoscopic brush cytology and biopsy in predicting residual esophageal adenocarcinoma

BACKGROUND

Esophageal adenocarcinoma generally carries a poor prognosis. Treatment with combination chemoradiation (CRT) followed by esophagectomy is becoming common. A pathologic complete response is uncommon but predicts improved survival. Identifying the subset of patients with residual carcinoma has potential management implications. Post-CRT endoscopic brush cytology and biopsy may detect residual tumor; however, the accuracy and clinical value of these methods remain unclear.

METHODS

Sixty-seven patients with esophageal adenocarcinoma who underwent preoperative CRT and post-CRT endoscopic brush cytology and biopsy followed by esophagectomy were identified. By using esophagectomy histology as the gold standard, the performance of cytology and biopsy was evaluated in diagnosing residual carcinoma. Two pathologists independently reviewed all false-negative and false-positive cases and resolved disagreements by consensus.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of cytology for diagnosing residual carcinoma were 26%, 95%, 92%, 35%, and 45%, respectively. For biopsy, these rates were 13%, 90%, 75%, 31%, and 36%, respectively. Sampling error accounted for false-negative diagnoses in approximately 66% of cytology analyses and 98% of biopsy analyses. Approximately 33% of false-negative cytology analyses and 1 false-negative biopsy analysis were caused by the under-recognition of tumor cells. Major diagnostic pitfalls included obscuring acute inflammation, necrosis, tumor cells that mimicked benign cells with radiation/reactive atypia, and the under recognition of mucin-containing adenocarcinoma cells.

CONCLUSIONS

Brush cytology and biopsy were specific but not sensitive methods for predicting residual cancer after CRT. However, cytology was superior. The current results indicated that brush cytology can be used alone to diagnose residual esophageal carcinoma, and awareness of specific diagnostic pitfalls will help pathologists improve its accuracy.

Lymph node staging in esophageal adenocarcinoma with PET-CT based on a visual analysis and based on metabolic parameters

BACKGROUND

In order to investigate the value of FDG positron emission tomography-computed tomography (PET-CT), FDG PET (reviewed side-by-side with CT), and metabolic parameters in the assessment of lymph node status and prognosis.

METHODS

Fifty-five subjects with lymph node positive (N1) and 26 subjects with lymph node negative (N0) disease were included. In the slice with the maximum FDG uptake of the tumor, the axial area of the primary tumor, the maximum diameter of the tumor, and the mean and maximum standardized uptake values were measured.

RESULTS

Fused PET-CT correctly characterized 289 of 325 lymph node groups (accuracy 89%) compared to 273 of 325 with PET (accuracy 84%). In lymph node staging (N0 vs. N1), PET-CT (accuracy 83%) was more accurate than PET (accuracy 78%). Among the metabolic parameters, the tumor diameter measured on PET-CT was the best predictor of lymph node stage (N0 vs. N1: accuracy 86%; threshold 25.5 mm) and overall survival. However, the highest accuracy of lymph node staging (N0 vs. N1) was achieved with the synergistic combination of visual analysis and primary tumor diameter measurements (accuracy 95%).

CONCLUSIONS

PET-CT increases accuracy of lymph node staging in esophageal adenocarcinoma compared to PET. The primary tumor diameter further improves accuracy in lymph node staging and was shown to be an independent predictor of overall survival.

Endosonographic staging of upper intestinal malignancy

Numerous studies conducted over the last 25 years provide evidence on the high diagnostic accuracy and important role of endoscopic ultrasonography (EUS) in staging oesophageal and gastric carcinoma. This extensive research was recently subjected to metaanalyses, condensing our knowledge on EUS performance and facilitating its comparison with competing methods. It is, however, important to realise that the management of oesophageal and gastric carcinoma is evolving and so are staging algorithms, setting new challenges for EUS and re-defining its position. Restaging after neoadjuvant treatment and precise assessment of early carcinoma before endoscopic treatment are areas of growing interest, but the role of EUS in these settings is rather limited. Rapidly developing cross-sectional imaging has the potential to challenge the position of EUS as the most accurate method in loco-regional staging. On the other hand, EUS guided fine-needle aspiration offers the unique opportunity to obtain cytological confirmation of lymph node metastases, with future potential for molecular staging.

PET, CT, and MR Imaging for Assessment of Thoracic Malignancy: Structure Meets Function

Imaging of patients with thoracic malignancy usually requires a multimodality approach. Each of these modalities has its own strengths and weaknesses. CT remains central to the staging and restaging of thoracic malignancies, but has recently been complemented with [18F]-2-fluoro-2-deoxy-D-glucose(FDG)-positron emission tomography (PET) imaging to maximize its potential. Furthermore, because FDG-PET/CT is useful at all stages of the workup and treatment of these patients, this modality has taken hold in the clinical realm for evaluation of patients with thoracic malignancy and is rapidly replacing PET-only imaging. MR imaging is also occasionally used in some patients with thoracic malignancies to improve disease staging or lesion characterization. PET/MR imaging may come to be used to evaluate patients with thoracic malignancies as well.