Neck ultrasound in staging squamous oesophageal carcinoma - a high yield technique

A Prospective Observational Study to Determine the Correlation of Clinical, Ultrasonography, and Pathological Examination of Cervical Lymph Nodal Staging in Oral Squamous Cell Carcinoma

Oral cancer is one of the most common cancers in our population. These cancers are drained by the nodes located in the cervical region which are easily accessible for clinical examination. However, these cervical nodes may also be enlarged due to various other nonmalignant causes. Hence, accuracy of clinical examination and ultrasound screening for cervical lymph nodes is invaluable. The aims of this study are (1) to correlate the clinical, radiological, and pathological results of cervical lymph nodes in patients with oral malignancy and (2) to calculate the accuracy of clinical and radiological methods in detecting malignant cervical lymph nodes. A prospective observational study was undertaken from January 2016 to December 2016 amounting to a total of 76 patients. All patients diagnosed with squamous cell carcinoma of the oral cavity and having a palpable neck node(s), who were planned for surgery were included. Clinical examination, ultrasonographic (USG) screening of the neck, and the final histopathology reports were noted. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for radiological screening by ultrasound were 90.5%, 90.9%, 79.2%, and 96.2%, respectively, and that for clinical examination were 61.9%, 69.1%, 43.3%, and 82.6%, respectively. Area under the curve (AUC) for ultrasound screening was 0.907, and the AUC for clinical examination was 0.655. Ultrasonography is a reliable, cost-effective imaging method in the assessment of malignant cervical nodes in patients with oral cancer, which is to be used along with clinical palpation for improving the accuracy of clinical staging and surgical planning preoperatively.

Accuracy of ultrasound for the diagnosis of cervical lymph node metastasis in esophageal cancer: a systematic review and meta-analysis

BACKGROUND

Esophageal cancer is considered a serious malignancy with respect to its prognosis and mortality rate. Cervical lymph node status is one of the keys to determining prognosis and treatment methods. However, published data vary regarding the accuracy of ultrasound in the diagnosis of cervical lymph node metastasis. We performed a meta-analysis to assess the efficacy of ultrasound for detecting cervical lymph node metastasis in patients with esophageal cancer.

METHODS

The PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane Library databases were searched to identify studies related to cervical lymph node metastasis, and 22 studies comprising 3,513 patients met our inclusion criteria. We used a bivariate meta-analysis following a random effects model to summarize the data. We also explored reasons for statistical heterogeneity using meta-regression, subgroup, and sensitivity analyses. Publication bias was assessed with a Deeks funnel plot.

RESULTS

The area under the receiver operating characteristic curve was 0.97 [95% confidence interval (CI): 0.95-0.98], and the pooled diagnostic odds ratio was 121.00 (95% CI: 47.57-307.79). With cut-off values of 5 mm and >5 mm for cervical lymph node size, the sensitivities and specificities (95% confidence interval) for ultrasound detection of cervical lymph node metastasis were 84% (67-93%) and 93% (90-95%); and 94% (76-98%) and 98% (89-100%), respectively.

CONCLUSIONS

We show for the first time the diagnostic accuracy of ultrasound for predicting cervical lymph node-positive metastasis in esophageal cancer. Our analysis shows that ultrasonography may be an effective and reliable approach to detect cervical lymph node metastasis in esophageal cancer. However, to accommodate heterogeneity, high-quality studies are needed to further verify the efficacy of ultrasound detection.

Endobronchial ultrasound: morphological predictors of benign disease

The objective of this study was to assess the utility of endobronchial ultrasound (EBUS) morphology of lymph nodes in predicting benign cytology of transbronchial needle aspirates in a prospective observational study. Five ultrasonic morphological characteristics of mediastinal and hilar lymph nodes were recorded: size, shape, margins, echogenic appearance and the presence of a central blood vessel. These characteristics were correlated with the final diagnosis. A total of 402 consecutive patients (237 males and 165 females) undergoing EBUS were studied. The final diagnosis was malignant disease in 244 (60.6%) and benign disease in 153 (38.05%) subjects. Out of 740 sampled nodes, in 463 (62.6%) malignant cells were identified, whereas in 270 (36.5%) nodes, no malignant cells were identified. On univariate analysis small size, triangular shape and the presence of a central vessel were predictive of a benign aetiology. In the final multivariate model, a predictive probability of 0.811 (95% CI 0.72-0.91) for benign disease was found if lymph node size was <10 mm and a central vessel was present. Sonographic appearances of lymph nodes improve the predictive probability of EBUS for benign aetiologies, and may reduce the number of nodes requiring sampling and the need for further invasive investigations.

Cervical lymph node metastases from remote primary tumor sites

Although most malignant lymphadenopathy in the neck represent lymphomas or metastases from head and neck primary tumors, occasionally, metastatic disease from remote, usually infraclavicular, sites presents as cervical lymphadenopathy with or without an obvious primary tumor. In general, these tumors metastasize to supraclavicular lymph nodes, but occasionally may present at an isolated higher neck level. A search for the primary tumor includes information gained by histology, immunohistochemistry, and evaluation of molecular markers that may be unique to the primary tumor site. In addition, 18F-fluoro-2-deoxyglocose positron emission tomography combined with CT (FDG-PET/CT) has greatly improved the ability to detect the location of an unknown primary tumor, particularly when in a remote location. Although cervical metastatic disease from a remote primary site is often incurable, there are situations in which meaningful survival can be achieved with appropriate local treatment. Management is quite complex and requires a truly multidisciplinary approach. © 2015 Wiley Periodicals, Inc. Head Neck 38: E2374-E2385, 2016.

Imaging in patients with merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine tumor of the skin with a mortality rate of approximately 25% (Peloschek et al., 2010). Accurate assessment of nodal involvement in patients with MCC predicts significantly overall outcome (Smith et al., 2012 and Ortin-Perez et al., 2007). Due to the rarity of this highly aggressive disease, only a few imaging reports on MCC were published, and subsequently still to date no accepted imaging algorithm for MCC is available. For primary staging of MCC, general recommendations have included ultrasonography, chest X-ray CT, and MRI, but recent articles show that the use of sentinel node and FDG-PET/PET-CT is gaining more and more importance.

The value of ultrasound in the assessment of cervical and abdominal lymph node metastases and selecting surgical strategy in patients with squamous cell carcinoma of the thoracic esophagus treated with neoadjuvant therapy

PURPOSE

To establish the role of ultrasound (US) in the assessment of cervical and abdominal lymph node metastases and its impact on making decision about surgical strategy in patients with squamous cell carcinoma of the thoracic esophagus.

MATERIAL/METHODS

The results of US lymph node assessment before and after a neoadjuvant treatment in 83 patients were compared with the results of histopathological evaluation of lymph nodes harvested during surgery (transthoracic esophagectomy and 2-field extended or 3-field lymph node dissection). A diagnostic value of cervical and abdominal US in terms of sensitivity, specificity, positive and negative predictive value after a neoadjuvant treatment were determined.

RESULTS

The sensitivity, specificity, positive and negative predictive value of the US assessment of cervical lymph node metastases were 100%, 96%, 81% and 100%, respectively. The sensitivity, specificity, positive and negative predictive value of the US assessment of abdominal lymph node metastases were 82%, 94%, 91.5% and 87%, respectively.

CONCLUSIONS

The high sensitivity and specificity of cervical US make this investigational method sufficient in the assessment of cervical nodal involvement. In esophageal cancer patients with negative cervical lymph nodes on US, three-field lymph node dissection could be avoided. In patients with positive cervical lymph nodes on US one should consider to extend lymph node dissection about lymph nodes of the neck to achieve a curative resection. In patients with negative abdominal US this investigation should be supplemented by more detailed diagnostic methods.

Supraclavicular metastases from distant primaries: what is the role of the head and neck surgeon?

Suspicious malignant supraclavicular lymphadenopathy provides a challenge for diagnosis and treatment. The wide variety of primary tumours that metastasise to this region should alert the clinician to look beyond the head and neck, particularly if it is the only site in the neck with suspected disease. As metastatic spread to these nodes from primaries not in the head and neck often indicates wide spread disease, neck dissection is controversial. In this article we review the lymphatic anatomy and discuss the investigation of supraclavicular lymphadenopathy. We discuss the evidence for the management of the neck in patients with subclavicular primary cancers (excluding lymphoma and melanoma) and the role of neck dissection.

Imaging of the cervical and abdominal lymph nodes in a combined treatment of squamous cell oesophageal carcinoma

The presence of lymph node metastases in esophageal cancer is one of the most principle prognostic indicators. The aim of the study was the assessment of cervical and abdominal lymph nodes (N/pN) by ultrasound (US) examination in patients with squamous cell carcinoma of the thoracic esophagus referred to esophagectomy.

MATERIAL AND METHODS

The analyzed study population consisted of 110 patients who underwent a combined-modality treatment (neoadjuvant chemotherapy - 74 patients or chemoradiotherapy - 36 patients). The results of US lymph node assessment were compared to the results of histopathological evaluation of lymph nodes harvested during surgery and diagnostic value of cervical and abdominal US in terms of sensitivity, specificity, positive and negative predictive value were determined.

RESULTS

The complete metastatic regression was shown by US in 14.3-22.2% of patients depending on the node location and mode of neoadjuwant treatment. There was no significant difference in the assessment of lymph nodes between chemotherapy and chemoradiotherapy patients.

CONCLUSIONS

US investigation is a method recommended for the assessment of metastatic lymph nodes in squamous cell oesophageal carcinoma, especially - for cervical nodes, where its specificity amounted to 96% and sensitivity - 100%. When positive nodes are suggested by US of the neck esophagectomy should be combined with 3-field lymphadenectomy.

Stomach cancer: prevalence and significance of neck nodal metastases on sonography

The aim of this study was to determine the frequency of metastatic neck nodes detected using sonography in patients with stomach cancer at presentation according to primary subsite and to assess the effect of metastatic neck node detection on tumour staging. Imaging and histological records of 233 patients diagnosed with stomach cancer were reviewed. All patients underwent neck ultrasound at presentation with ultrasound-guided fine needle aspiration for cytology (FNAC) of sonographically abnormal neck nodes. Abnormal nodes were classified positive or negative for metastases based on the FNAC result. Clinical records were also reviewed for evidence of subsequent neck nodal metastases. Sonographically abnormal neck nodes were present in 14/233 (6.0%) patients; 7 were reactive and 7 were metastatic based on FNAC findings and clinical follow-up. Overall, 7/233 (3.0%) patients with stomach cancer had nodal metastases, although tumour stage was altered in only 2/233 (0.9%) patients; 57% of metastatic nodes were impalpable. Nodal metastases from gastric cardia tumours (6%) were more common than from the body (2%) or antrum (3%). Neck node metastases are uncommon in stomach cancer at presentation, are usually associated with extensive intra-abdominal metastatic spread, and adversely influence tumour staging in only a small minority of patients.

Diagnostic imaging in Merkel cell carcinoma: lessons to learn from 16 cases with correlation of sonography, CT, MRI and PET

OBJECTIVE

The authors report imaging findings in a series of 16 patients with MCC, a rare tumour which is often managed primarily by a dermatologist. To our knowledge, no equivalent series of MCC has been described in the nuclear medicine literature.

MATERIAL AND METHODS

In this IRB-approved retrospective noncomparative case series 16 patients with biopsy-proven Merkel cell carcinoma were included between January 1999 and October 2007. Twenty-nine whole body PET scans (18F-FDG n=24, 18F-FDOPA n=5) in 16 patients were retrospectively reviewed with regard to tracer uptake in six anatomical sites per patient. For 127/144 of FDG-PET evaluated regions and 68/144 of regions depicted by conventional imaging methods, a valid standard of reference could be obtained. A combined standard of reference was applied, which consisted of histopathology (lymphadenectomy or biopsy) or clinical or radiological follow-up for at least 12 months.

RESULTS

the mean FDG uptake over the clinicopatholigical verified FDG avid areas was 4.7 SUV (1.5-9.9 SUV). The region based assessment of diagnostic value, in consideration of the standard of reference, resulted in a sensitivity of 85.7% and a specificity of 96.2% of FDG-PET (n=127) and in a combined sensitivity of 95.5% and a specificity of 89.1% for morphological imaging methods (n=68). Differences between methods did not reach statistical significance (p=1.00, p=0.18).

CONCLUSIONS

FDG-PET is a highly useful whole body staging method of comparable value compared to conventional imaging methods with restricted field of view. The lessons learned from case series are discussed.

Concurrent chemoradiotherapy or endoscopic stenting for advanced squamous cell carcinoma of esophagus: a case-control study

BACKGROUND

We evaluated the role of chemoradiotherapy (CRT) for patients with inoperable squamous esophageal cancer.

METHODS

Patients with locally advanced or metastatic squamous esophageal carcinoma who received CRT were recruited. The CRT consists of continuous infusion of 5-fluorouracil at 200 mg/m(2)/day, and cisplatin at 60 mg/m(2) on days 1 and 22, with concurrent radiotherapy for a total of 50 to 60 Gy in 25 to 30 fractions over 6 weeks. Efficacy was assessed by endoscopy and computed tomographic scan before and 8 weeks after completion of the treatment program. Median survival and the need for palliative esophageal stenting were compared with another group of patients who received endoscopic stenting.

RESULTS

From 1996 to 2003, a total of 36 consecutive patients (33 male, mean +/- SD age 63.2 +/- 9.5 years) with T4 disease (81%) with or without cervical nodal metastasis (50%) received CRT, while 36 patients treated with endoscopic stenting alone were recruited as controls. Both groups were comparable in demographics, pretreatment dysphagia score, comorbidities, and tumor characteristics. CRT was completed in 32 patients (89%). There was no treatment-related mortality. Tumor volume was greatly reduced after CRT in 19 patients. Four patients (11%) received salvage esophagectomy 9 to 42 months after CRT. Compared with the stenting group, CRT statistically significantly improved 5-year survival (15% vs. 0%, P = .01), median survival (10.8 months vs. 4.0 months, P < .005), and need for stenting (22% vs. 100%, P = .005).

CONCLUSIONS

Palliative CRT can effectively improve the symptoms of dysphagia in patients with inoperable squamous esophageal carcinoma. It results in better survival compared with endoscopic stenting in these patients.

Ultrasound, computed tomography, or the combination for the detection of supraclavicular lymph nodes in patients with esophageal or gastric cardia cancer: a comparative study

BACKGROUND AND OBJECTIVES

Both ultrasound (US) and computed tomography (CT) can be used to detect supraclavicular lymph node metastases. Aim was to compare US, US plus fine-needle aspiration (US-FNA), CT, US + CT, and US-FNA + CT for the detection of these metastases in esophageal or gastric cardia cancer patients.

METHODS

Between 1994 and 2004, 567 patients underwent US and CT for esophageal or gastric cardia cancer staging. Gold standard was postoperative detection of lymph nodes in the resected specimen, FNA, or a radiological result with follow-up.

RESULTS

Sensitivities of US (75%), US-FNA (72%), US + CT (80%), and US-FNA + CT (79%) were higher than sensitivity of CT alone (25%) (P < 0.001). Specificities were high for US-FNA (100%), CT (99%), and US-FNA + CT (99%), whereas those of US alone (91%) and US + CT (91%) were lower (P < 0.001). In 4/65 (6%) patients with true-positive malignant lymph nodes, CT was positive with US and/or US-FNA being negative. However, in 36/65 (55%) patients, US and/or US-FNA were positive with CT being negative.

CONCLUSION

US-FNA seems the preferred diagnostic modality for the detection of supraclavicular lymph node metastases in patients with esophageal or gastric cardia cancer. Sensitivity of metastases detection only slightly improves if US-FNA is combined with CT. A prospective, comparative study is however needed.

Detection of distant metastases in patients with oesophageal or gastric cardia cancer: a diagnostic decision analysis

Computed tomography (CT) is presently a standard procedure for the detection of distant metastases in patients with oesophageal or gastric cardia cancer. We aimed to determine the additional diagnostic value of alternative staging investigations. We included 569 oesophageal or gastric cardia cancer patients who had undergone CT neck/thorax/abdomen, ultrasound (US) abdomen, US neck, endoscopic ultrasonography (EUS), and/or chest X-ray for staging. Sensitivity and specificity were first determined at an organ level (results of investigations, i.e., CT, US abdomen, US neck, EUS, and chest X-ray, per organ), and then at a patient level (results for combinations of investigations), considering that the detection of distant metastases is a contraindication to surgery. For this, we compared three strategies for each organ: CT alone, CT plus another investigation if CT was negative for metastases (one-positive scenario), and CT plus another investigation if CT was positive, but requiring that both were positive for a final positive result (two-positive scenario). In addition, costs, life expectancy and quality adjusted life years (QALYs) were compared between different diagnostic strategies. CT showed sensitivities for detecting metastases in celiac lymph nodes, liver and lung of 69, 73, and 90%, respectively, which was higher than the sensitivities of US abdomen (44% for celiac lymph nodes and 65% for liver metastases), EUS (38% for celiac lymph nodes), and chest X-ray (68% for lung metastases). In contrast, US neck showed a higher sensitivity for the detection of malignant supraclavicular lymph nodes than CT (85 vs 28%). At a patient level, sensitivity for detecting distant metastases was 66% and specificity was 95% if only CT was performed. A higher sensitivity (86%) was achieved when US neck was added to CT (one-positive scenario), at the same specificity (95%). This strategy resulted in lower costs compared to CT only, at an almost similar (quality adjusted) life expectancy. Slightly higher specificities (97–99%) were achieved if liver and/or lung metastases found on CT, were confirmed by US abdomen or chest X-ray, respectively (two-positive scenario). These strategies had only slightly higher QALYs, but substantially higher costs. The combination of CT neck/thorax/abdomen and US neck was most cost-effective for the detection of metastases in patients with oesophageal or gastric cardia cancer, whereas the performance of CT only had a lower sensitivity for metastases detection and higher costs. The role of EUS seems limited, which may be due to the low number of M1b celiac lymph nodes detected in this series. It remains to be determined whether the application of positron emission tomography will further increase sensitivities and specificities of metastases detection without jeopardising costs and QALYs.

Modified technique of high-resolution ultrasonography of the normal cervical esophagus

BACKGROUND AND AIM

To study a modified technique of neck ultrasound for the visualization of cervical esophagus using a high-resolution and high frequency linear transducer in normal subjects.

METHODS

Consecutive control subjects were patients who underwent abdominal sonography for other diseases and had no past or current history of dysphagia or esophageal disorders. The thyroid gland was used as a transducer window to obtain images. We used a slightly flexed neck position with the head turned 45 degrees to the opposite side while scanning the neck on either side.

RESULTS

One-hundred subjects were scanned and their age range was 10-74 years (male:female ratio 1:1). In 36% of cases it was difficult to visualize the right lateral 2/3rd in the traditional scanning position of the neck. This improved to 2% with the modified neck position. All patients had the left window visualized with both neck positions. The transverse diameter, anterior-posterior diameter and wall thickness measures were all significantly greater with the modified technique. All patients tolerated the procedure with no reported discomfort.

CONCLUSIONS

This modified technique provides superior views of the cervical esophagus, particularly from the right window, in almost all patients. Normal parameters using ultrasound have now been established.

The role of socio-economic status in the decision making on diagnosis and treatment of oesophageal cancer in The Netherlands

In the United States (USA), a correlation has been demonstrated between socio-economic status (SES) of patients on the one hand, and tumour histology, stage of the disease and treatment modality of various cancer types on the other hand. It is unknown whether such correlations are also involved in patients with oesophageal cancer in The Netherlands. Between 1994 and 2003, 888 oesophageal cancer patients were included in a prospective database with findings on the diagnostic work-up and treatment of oesophageal cancer. Socio-economic status of patients was defined as the average net yearly income. Linear-by-linear association testing revealed that oesophageal adenocarcinoma was more frequently observed in patients with higher SES and squamous cell carcinoma in patients with lower SES (P=0.02). Multivariable logistic regression analysis showed no correlation between SES and staging procedures and preoperative TNM stage. The adjusted odds ratio (OR) for stent placement was 0.82 (95% CI 0.71–0.95), indicating that with an increase in SES by 1200 €, the likelihood that a stent was placed declined by 18%. Patients with a higher SES more frequently underwent resection or were treated with chemotherapy (OR: 1.15; 95% CI 1.01–1.32 and OR: 1.16; 95% CI 1.02–1.32, respectively). Socio-economic factors are involved in oesophageal cancer in The Netherlands, as patients with a higher SES are more likely to have an adenocarcinoma and patients with a lower SES a squamous cell carcinoma. Moreover, the correlations between SES and different treatment modalities suggest that both patient and doctor determinants contribute to the decision on the most optimal treatment modality in patients with oesophageal cancer.

Prediction of lymph node metastases in vulvar cancer: a review

The aim of this study was to review the literature on currently available non- and minimally-invasive diagnostic methods and analysis of primary tumor characteristics for prediction of inguinofemoral lymph node metastases in patients with primary squamous cell carcinoma of the vulva. We used the English language literature in PubMed and reference lists from selected articles. Search terms included vulvar carcinoma, prognosis, lymph node metastases, ultrasound, computer tomography, magnetic resonance imaging, positron emission tomography, and sentinel lymph node. No study type restrictions were imposed. Currently no noninvasive imaging techniques exist that are able to predict lymph node metastases with a high enough negative predictive value. A depth of invasion < or =1 mm is the only histopathologic parameter that can exclude patients for complete inguinofemoral lymphadenectomy. No other clinicopathologic parameter allows exclusion of lymph node metastases with a high enough negative predictive value. The minimally invasive sentinel node procedure is a promising technique for selecting patients for complete lymphadenectomy, but its safety has not been proven yet.

A comparison between low-volume referring regional centers and a high-volume referral center in quality of preoperative metastasis detection in esophageal carcinoma

BACKGROUND AND AIM

An inverse correlation between hospital volume and esophageal resection mortality has been reported. In this study, we compared the quality of preoperative metastasis detection between a high-volume referral center with that of low-volume referring regional centers.

METHODS

In 573 patients diagnosed with esophageal cancer (1994-2003), the results of preoperative staging investigations (CT-scan, ultrasound of abdomen and neck, and chest x-ray) performed in 61 regional centers were re-evaluated and/or repeated in one referral center. The gold standards were a radiological result with > or =6 months follow-up, fine-needle aspiration, or the postoperative TNM-stage.

RESULTS

In the same group of patients, the preoperative investigations performed in regional centers detected true-positive malignant lymph nodes in 8% of patients and true-positive distant metastases in 7% of patients, whereas these percentages were 16% and 20%, respectively, in the referral center. In 72/573 (13%) patients, one or more metastases detected in the referral center had been missed in the regional centers. After allowing resectability in the presence of M1a lymph nodes, this would still have resulted in futile esophageal resections in 6% of patients. In contrast to the higher diagnostic sensitivity in the referral center, specificity was comparable between referral and regional centers.

CONCLUSIONS

This study found that, in assessing the operability of esophageal cancer, the diagnostic sensitivity of metastasis detection in a high-volume referral center was higher than that in referring regional centers. This resulted from both better CT-scanning equipment and more experienced radiologists in the referral center. Should the decision to perform esophagectomy have only been based on metastasis detection in these regional centers, over 1 in 20 patients would have undergone resection in the presence of metastases.

The clinical efficacy of neoadjuvant chemotherapy in squamous esophageal cancer: a prospective nonrandomized study of pulse and continuous-infusion regimens with Cisplatin and 5-Fluorouracil

BACKGROUND

We evaluated cisplatin and 5-fluorouracil as preoperative adjuvant chemotherapy for patients with locally advanced squamous esophageal cancer and compared two different infusion regimens. The outcomes were also compared with those of our historical control patients treated by surgery alone.

METHODS

From 1991 to 1997, 83 consecutive esophageal cancer patients underwent surgical exploration after completion of two cycles of cisplatin and 5-fluorouracil chemotherapy regimens, either in pulse or in continuous infusion cycles. Outcomes were compared with those of 76 historical control patients. Both groups were comparable in demographic characteristics and tumor stages. The resection rates, operative morbidity, mortality, and survival rates were compared.

RESULTS

Partial response was achieved in 50% of patients who received chemotherapy. There was no chemotherapy-related mortality. The resection, morbidity, and mortality rates and median survival between the surgery-alone group and the chemotherapy group were 71.1% vs. 82%, 51% vs. 55%, and 4% vs. 10.8%, 12.0 vs. 13.5 months, respectively (P >.05). There was also no statistically significant difference between the two regimens.

CONCLUSIONS

Preoperative adjuvant chemotherapy with cisplatin and 5-fluorouracil infusion, in pulse or continuous regimens, followed by surgery for squamous esophageal cancer patients had no added benefit in the overall survival.

[Gross tumor volume and clinical target volume: esophageal tumors]

The oesophagus is divided into four regions: cervical oesophagus, and intrathoracic oesophagus with an upper, mid- and lower thoracic portion. Cancer may occur on each of these regions. Computed tomography of the thorax and superior abdomen and endoscopic ultrasound are necessary for reliable staging. CT simulation allows accurate definition of tumour volume. GTV includes tumour volume and regional lymph nodes. CTV encompasses GTV plus a safety margin and lymph node areas considered to harbour potential microscopic disease. The extent of prophylactic lymph node irradiation depends on the anatomic location of the primary tumour.