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Does ligation of the thoracic duct during oesophagectomy reduce the incidence of post-operative chylothorax?
REVIEW International Journal of Surgery 10 (2012) 203e205
Contents lists available at SciVerse ScienceDirect
International Journal of Surgery journal homepage: www.theijs.com
Review
Does ligation of the thoracic duct during oesophagectomy reduce the incidence of post-operative chylothorax? Clarisa T.P. Choh a, Omar A. Khan b, *, Igor J. Rychlik c, Kieran McManus c a
Department of Surgery, Royal Hampshire County Hospital, Winchester, UK Department of Upper GI Surgery, St Georges Hospital, London SW17 0QT, UK c Department of Cardiothoracic Surgery, Royal Victoria Hospital, Belfast, UK b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 21 February 2012 Received in revised form 13 March 2012 Accepted 14 March 2012 Available online 21 March 2012
A best evidence topic in surgery was written according to a structured protocol. The question addressed was whether prophylactic thoracic duct ligation during oesophagectomy results in a lower incidence of post-operative chylothorax. 29 relevant papers were found using the reported search, of which 5 papers represented the best evidence to answer the clinical question. The authors, date and country of publication, patient group, study type, relevant outcomes and results of these papers are tabulated. Of these studies, only one was a prospective randomised controlled study with sizeable patient numbers. This was also the most recent study and demonstrated a significant decrease in post-operative chylothorax incidence following intra-operative thoracic duct ligation. Of the four remaining retrospective studies, one showed an increase in chylothorax rate following ligation whilst three showed a reduction in the incidence of chylothorax (although in only one of these three studies was this decrease statistically significantly). We conclude that for patients undergoing oesophagectomy, although there are conflicting results from retrospective studies, prospective randomised controlled trial evidence points to prophylactic ligation of the thoracic duct as an effective measure to reduce the incidence of post-operative chylothorax. Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Oesophagectomy Chylothorax Thoracic duct ligation
1. Introduction
3. Three-part question
A best evidence article was constructed according to a structured protocol as described in a previous publication the International Journal of Surgery.1
In [patients who undergo an oesophagectomy], does [intraoperative ligation of the thoracic duct] reduce the incidence of [post-operative chylothorax]?
2. Clinical scenario
4. Search strategy
You are performing an Ivor-Lewis oesophagectomy for a gastrooesophageal junctional oesophageal cancer. You have completed the abdominal portion of the procedure and are about to perform a right thoracotomy to mobilise the oesophagus. Your assistant asks if you plan to ligate the thoracic duct as he has heard it reduces the incidence of post-operative chylothorax. Although this is not part of your routine practice, you resolve to check the literature.
Medline 1966 to June 2011 using OVID interface for the terms [Oesophagectomy.mp OR esophagectomy.mp] AND [chylothorax.mp] AND [thoracic duct ligation.mp]. In addition, the reference lists of the relevant papers were also searched.
* Corresponding author. Tel./fax: þ44 2087253591. E-mail address: [email protected] (O.A. Khan).
5. Search outcome 29 papers were found using the reported search. Abstracts were searched and only those papers which directly compared the incidence of chylothorax in patients who underwent prophylactic ligation with those who had conservative treatment were selected. This yielded five papers (3 of which were in
1743-9191/$ e see front matter Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijsu.2012.03.011
REVIEW 204
C.T.P. Choh et al. / International Journal of Surgery 10 (2012) 203e205
English and 2 were in Mandarin Chinese) and these were therefore chosen as representing the best relevant evidence to answer this clinical question. 6. Results The results of the five papers are summarised in Table 1. 7. Discussion Post-operative chylothorax is a rare but potentially dangerous complication of oesophagectomy, as it results in malnutrition and immunosuppression and is associated with a high mortality rate.2 In the past decade, there has been some suggestion that routine identification and ligation of the thoracic duct may be of benefit during transthoracic oesophagectomy in reducing incidence of post-operative chylothorax formation. Dougenis et al.3 performed a retrospective analysis of 255 patients which compared elective thoracic duct ligation (n ¼ 189) against patients who had their thoracic ducts preserved (n ¼ 66). This study demonstrated a statistically significant reduction in chylothorax rates in patients who had ligation. Similarly, Cagol et al.4 also showed a reduction in incidence of chylothorax rates in the ligation group, however, their overall incidence of post-operative chylothorax was very low and no statistical analysis was performed. Lu et al.5 also found
a reduction in chylothorax rates in their study of 243 patients, but this was not statistically significant. In complete contrast, Fu et al.6 undertook a study of 389 patients which showed a statistically significant increase in post-operative chylothorax following ligation. Interestingly, all of the papers showed that the development of chylothorax led to adverse clinical consequences resulting in a mortality rate of around 20%.3e7 This therefore implies that reduction of chylothorax rates is an important clinical goal. It should be noted that prior to 2011, all studies on this topic were retrospective in nature.3e6 The only large-scale prospective study on this subject was recently published by Lai et al,7 who conducted a trial of 653 transthoracic oesophagectomy patients and randomised them to a ligation group and a preservation group. The demographic details in both groups were similar however they noted a statistically significant reduction in chylothorax rates in the ligation group. In particular, the ligation group had only 1 patient with a chylothorax (which resulted in no adverse clinical sequelae) whilst 7 patients in the preservation group had chylothoraces (of whom 4 had significant clinical complications secondary to the chylothorax resulting in 2 deaths). With respect to the potential complications associated with the process of ligation itself, the only comprehensive study on this subject was conducted by Fu et al.4 This study, which unlike all previous studies showed an increase in chylothorax rates after ligation, also analysed the impact of ligation itself on post-operative
Table 1 Best evidence papers. Author, date and country
Patient group
Study type, level of evidence
Dougenis et al., 255 patients underwent Single centre retrospective 1992 Scotland, transthoracic oesophagectomy study Level III UK 189 had elective intra-operative ligation of thoracic duct
Outcomes
Key results
Comments
Chylothorax rate (ligation vs. preservation group) Overall post-operative complication rate Overall post-operative mortality rate
2.1% vs 9% (p < 0.05) Not stated
This initial study showed a significant decrease in incidence of chylothorax in ligation group. It should be noted that the overall mortality rate in the ligation group was high 10%. This study showed significant increase in the incidence of chylothorax rate following prophylactic thoracic duct ligation. Complication rate in ligation group were also higher, but not statistically significant and the long-term survival rates were comparable. This study found no significant difference in chylothorax rates between ligation and non-ligation subgroups. It should be noted that the overall mortality of the cohort is very low at 0.82%. This study advocates intra-operative mass thoracic duct ligation as a safe and preventative method for chylothorax prevention. However, the study did not statistically analyse chylothorax rates of both groups, and did not state the overall complication and mortality rates of the two groups. This study supported the notion of thoracic duct ligation. 1 patient in the ligation group had a chylothorax with no clinical significance. 7 patients in preservation group had chylothoraces resulting in 4 complications (chest infection, ARDS, MOF in 2) which in turn led to 2 deaths)
Not stated
Fu et al., 2006 China
389 patients who underwent transthoracic oesophagectomy 171 patients received thoracic duct ligation, and 218 had thoracic duct preserved
Single centre retrospective Chylothorax rate (ligation vs. cohort study Level III preservation group) Overall post-operative complication rate Overall post-operative mortality rate 5-year survival rates
1.17% vs 0.46% (p < 0.001) 18.2% vs 11.5% (p ¼ 0.063) 1.75% vs 0.92% (p ¼ 0.658) 29.2% vs 29.8% (p ¼ 0.902)
Lu et al., 2008 China
243 patients underwent transthoracic oesophagectomy Divided by tumour localization, then subdivided into ligation (117 patients) and preservation groups (126 patients). 1775 patients who had undergone transthoracic oesophagectomy 1452 were performed without thoracic duct ligation (1980e2000), and 323 had intra-operative thoracic duct ligation (2001e2006)
Single centre retrospective Chylothorax rate (ligation study Level III group vs. preservation group) Overall post-operative complication rate Overall post-operative mortality rate Single centre retrospective Chylothorax rate (ligation and prospective cohort group vs. preservation group) study Level III Overall post-operative complication rate Overall post-operative mortality rate
2.1% vs 3.7% (p > 0.05) Not stated
653 patients who underwent transthoracic oesophagectomy were divided into 2 groups e 325 patients had thoracic duct ligation during surgery; 328 patients were in the preservation group
Single centre prospective RCT Level II
0.3% vs 2.1% (p [ 0.046) Not stated Not stated
Cagol et al., 2009 Italy
Lai et al., 2011 China
Bold signifies p values of less than 0.05.
Chylothorax rate (ligation group vs. preservation group) Overall complication rate Overall mortality rate
Not stated 0% vs 0.9% Not stated Not stated
REVIEW C.T.P. Choh et al. / International Journal of Surgery 10 (2012) 203e205
outcomes unrelated to chylothorax. They found an increased mortality rate and complication rate in the ligation group, but this was not statistically significant. Interestingly, they noted no advantage or detriment in long-term survival rates of patients who underwent ligation. It should be noted that Cagol et al.5 and Lai et al.7 stated their cohorts had no complications or deaths related to the process of ligation. However, they do not state the comparative morbidity or mortality rates of the two groups; hence their conclusions cannot be validated. Moreover on reviewing the evidence, there does not appear to be standard technique for thoracic duct ligation. For example, Cagol et al.5 described mass ligation using absorbable polyglactin, whilst Lai et al.7 also performed mass ligation using three non-absorbable sutures. In addition, there is to date no data on the efficacy of mass ligation versus formal identification and ligation (or indeed excision of a segment) of the thoracic duct. Finally there have been no studies comparing suture ligation with mechanical ligation or ligation using energy devices. There are a number of limitations in all of these studies which require discussion. For a start, there is some evidence to suggest that the site of the tumour has an impact on the incidence of chylothorax,6 and this may be a statistical confounder in analysing the results of all of these studies. Similarly, Bolgar et al.8 have suggested that histological type of the tumour and lymph node involvement may affect chylothorax rates, and these factors are further potential statistical confounders. In addition, there is some heterogeneity in the pre-operative management of the patients in these studies. For instance, in the study by Cagol et al.,5 half the patients received pre-operative chemoradiotherapy. More fundamentally, none of the papers had a standardized definition of what volume of chest drain output constitutes a post-operative chylothorax. Finally, with the exception of the paper by Fu et al.,4 there is no data on the overall complication, mortality, survival rate and the potential long-term oncological impact of ligating the thoracic duct. In summary, on reviewing the data, as the only prospective randomised controlled study with sizeable patient numbers demonstrated a significant decrease in post-operative chylothorax rates following intra-operative thoracic duct ligation, we concur with their conclusion that patients undergoing oesophagectomy should have prophylactic thoracic duct ligation. However, the impact of thoracic duct ligation on overall post-operative complications as well as long-term oncological outcomes have yet to be definitively assessed and proven. 8. Clinical bottom line For patients undergoing oesophagectomy, although there are conflicting results from retrospective studies, prospective
205
randomised controlled trial evidence points to prophylactic ligation of the thoracic duct as an effective measure to reduce the incidence of post-operative chylothorax.
Conflict of interest None declared.
Funding None declared.
Ethical approval None declared.
Author contribution Clarissa Cho - Literature search, analysis, writing Omar Khan - Analysis and editing of manuscript Igor J. Rychlik - Literature search, analysis and editing of manuscript Kieran McManus - Analysis and editing of manuscript
References 1. Khan OA, Dunning J, Parvaiz AC, Agha R, Rosin D, Mackway-Jones K. Towards evidence-based medicine in general surgical practice: best BETs. Int J Surg 2011;9:585e8. 2. Wemyss-Holden SA, Launois B, Maddern GJ. Management of thoracic duct injuries after oesophagectomy. Br J Surg 2001;88(11):1442e8. 3. Dougenis D, Walker WS, Cameron EW, Walbaum PR. Management of chylothorax complicating extensive oesophageal resection. Surg Gynecol Obstet 1992;174(6):501e6. 4. Cagol M, Ruol A, Castoro C, Alfieri R, Michieletto S, Ancona E. Prophylactic thoracic duct mass ligation prevents chylothorax after transthoracic oesophagectomy for cancer. World J Surg 2009;8:1684e6. 5. Lu JJ, Hou BP, Yao D, Zhang W, Qin CW, Ma J, et al. Effect of thoracic duct ligation during transthoracic oesophagectomy on the prevention of post-operative chylothorax in different tumour locations [Chinese]. Zhonghua Wei Chang Wai Ke Za Zhi 2008;11(1):36e8. 6. Fu JH, Hu Y, Huang WZ, Yang H, Zhu ZH, Zheng B. Evaluating prophylactic ligation of thoracic duct during radical resection of oesophageal carcinoma [Chinese]. Ai Zheng 2006;25(6):728e30. 7. Lai FC, Chen L, Tu YR, Lin M, Li X. Prevention of chylothorax complicating extensive oesophageal resection by mass ligation of thoracic duct: a random control study. Ann Thorac Surg 2011;91(6):1770e4. 8. Bolgar C, Walsh TN, Tanner NA, Keeling P, Hennessy TP. Chylothorax after oesophagectomy. Br J Surg 1991;78(5):587e8.
Contents lists available at SciVerse ScienceDirect
International Journal of Surgery journal homepage: www.theijs.com
Review
Does ligation of the thoracic duct during oesophagectomy reduce the incidence of post-operative chylothorax? Clarisa T.P. Choh a, Omar A. Khan b, *, Igor J. Rychlik c, Kieran McManus c a
Department of Surgery, Royal Hampshire County Hospital, Winchester, UK Department of Upper GI Surgery, St Georges Hospital, London SW17 0QT, UK c Department of Cardiothoracic Surgery, Royal Victoria Hospital, Belfast, UK b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 21 February 2012 Received in revised form 13 March 2012 Accepted 14 March 2012 Available online 21 March 2012
A best evidence topic in surgery was written according to a structured protocol. The question addressed was whether prophylactic thoracic duct ligation during oesophagectomy results in a lower incidence of post-operative chylothorax. 29 relevant papers were found using the reported search, of which 5 papers represented the best evidence to answer the clinical question. The authors, date and country of publication, patient group, study type, relevant outcomes and results of these papers are tabulated. Of these studies, only one was a prospective randomised controlled study with sizeable patient numbers. This was also the most recent study and demonstrated a significant decrease in post-operative chylothorax incidence following intra-operative thoracic duct ligation. Of the four remaining retrospective studies, one showed an increase in chylothorax rate following ligation whilst three showed a reduction in the incidence of chylothorax (although in only one of these three studies was this decrease statistically significantly). We conclude that for patients undergoing oesophagectomy, although there are conflicting results from retrospective studies, prospective randomised controlled trial evidence points to prophylactic ligation of the thoracic duct as an effective measure to reduce the incidence of post-operative chylothorax. Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Oesophagectomy Chylothorax Thoracic duct ligation
1. Introduction
3. Three-part question
A best evidence article was constructed according to a structured protocol as described in a previous publication the International Journal of Surgery.1
In [patients who undergo an oesophagectomy], does [intraoperative ligation of the thoracic duct] reduce the incidence of [post-operative chylothorax]?
2. Clinical scenario
4. Search strategy
You are performing an Ivor-Lewis oesophagectomy for a gastrooesophageal junctional oesophageal cancer. You have completed the abdominal portion of the procedure and are about to perform a right thoracotomy to mobilise the oesophagus. Your assistant asks if you plan to ligate the thoracic duct as he has heard it reduces the incidence of post-operative chylothorax. Although this is not part of your routine practice, you resolve to check the literature.
Medline 1966 to June 2011 using OVID interface for the terms [Oesophagectomy.mp OR esophagectomy.mp] AND [chylothorax.mp] AND [thoracic duct ligation.mp]. In addition, the reference lists of the relevant papers were also searched.
* Corresponding author. Tel./fax: þ44 2087253591. E-mail address: [email protected] (O.A. Khan).
5. Search outcome 29 papers were found using the reported search. Abstracts were searched and only those papers which directly compared the incidence of chylothorax in patients who underwent prophylactic ligation with those who had conservative treatment were selected. This yielded five papers (3 of which were in
1743-9191/$ e see front matter Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijsu.2012.03.011
REVIEW 204
C.T.P. Choh et al. / International Journal of Surgery 10 (2012) 203e205
English and 2 were in Mandarin Chinese) and these were therefore chosen as representing the best relevant evidence to answer this clinical question. 6. Results The results of the five papers are summarised in Table 1. 7. Discussion Post-operative chylothorax is a rare but potentially dangerous complication of oesophagectomy, as it results in malnutrition and immunosuppression and is associated with a high mortality rate.2 In the past decade, there has been some suggestion that routine identification and ligation of the thoracic duct may be of benefit during transthoracic oesophagectomy in reducing incidence of post-operative chylothorax formation. Dougenis et al.3 performed a retrospective analysis of 255 patients which compared elective thoracic duct ligation (n ¼ 189) against patients who had their thoracic ducts preserved (n ¼ 66). This study demonstrated a statistically significant reduction in chylothorax rates in patients who had ligation. Similarly, Cagol et al.4 also showed a reduction in incidence of chylothorax rates in the ligation group, however, their overall incidence of post-operative chylothorax was very low and no statistical analysis was performed. Lu et al.5 also found
a reduction in chylothorax rates in their study of 243 patients, but this was not statistically significant. In complete contrast, Fu et al.6 undertook a study of 389 patients which showed a statistically significant increase in post-operative chylothorax following ligation. Interestingly, all of the papers showed that the development of chylothorax led to adverse clinical consequences resulting in a mortality rate of around 20%.3e7 This therefore implies that reduction of chylothorax rates is an important clinical goal. It should be noted that prior to 2011, all studies on this topic were retrospective in nature.3e6 The only large-scale prospective study on this subject was recently published by Lai et al,7 who conducted a trial of 653 transthoracic oesophagectomy patients and randomised them to a ligation group and a preservation group. The demographic details in both groups were similar however they noted a statistically significant reduction in chylothorax rates in the ligation group. In particular, the ligation group had only 1 patient with a chylothorax (which resulted in no adverse clinical sequelae) whilst 7 patients in the preservation group had chylothoraces (of whom 4 had significant clinical complications secondary to the chylothorax resulting in 2 deaths). With respect to the potential complications associated with the process of ligation itself, the only comprehensive study on this subject was conducted by Fu et al.4 This study, which unlike all previous studies showed an increase in chylothorax rates after ligation, also analysed the impact of ligation itself on post-operative
Table 1 Best evidence papers. Author, date and country
Patient group
Study type, level of evidence
Dougenis et al., 255 patients underwent Single centre retrospective 1992 Scotland, transthoracic oesophagectomy study Level III UK 189 had elective intra-operative ligation of thoracic duct
Outcomes
Key results
Comments
Chylothorax rate (ligation vs. preservation group) Overall post-operative complication rate Overall post-operative mortality rate
2.1% vs 9% (p < 0.05) Not stated
This initial study showed a significant decrease in incidence of chylothorax in ligation group. It should be noted that the overall mortality rate in the ligation group was high 10%. This study showed significant increase in the incidence of chylothorax rate following prophylactic thoracic duct ligation. Complication rate in ligation group were also higher, but not statistically significant and the long-term survival rates were comparable. This study found no significant difference in chylothorax rates between ligation and non-ligation subgroups. It should be noted that the overall mortality of the cohort is very low at 0.82%. This study advocates intra-operative mass thoracic duct ligation as a safe and preventative method for chylothorax prevention. However, the study did not statistically analyse chylothorax rates of both groups, and did not state the overall complication and mortality rates of the two groups. This study supported the notion of thoracic duct ligation. 1 patient in the ligation group had a chylothorax with no clinical significance. 7 patients in preservation group had chylothoraces resulting in 4 complications (chest infection, ARDS, MOF in 2) which in turn led to 2 deaths)
Not stated
Fu et al., 2006 China
389 patients who underwent transthoracic oesophagectomy 171 patients received thoracic duct ligation, and 218 had thoracic duct preserved
Single centre retrospective Chylothorax rate (ligation vs. cohort study Level III preservation group) Overall post-operative complication rate Overall post-operative mortality rate 5-year survival rates
1.17% vs 0.46% (p < 0.001) 18.2% vs 11.5% (p ¼ 0.063) 1.75% vs 0.92% (p ¼ 0.658) 29.2% vs 29.8% (p ¼ 0.902)
Lu et al., 2008 China
243 patients underwent transthoracic oesophagectomy Divided by tumour localization, then subdivided into ligation (117 patients) and preservation groups (126 patients). 1775 patients who had undergone transthoracic oesophagectomy 1452 were performed without thoracic duct ligation (1980e2000), and 323 had intra-operative thoracic duct ligation (2001e2006)
Single centre retrospective Chylothorax rate (ligation study Level III group vs. preservation group) Overall post-operative complication rate Overall post-operative mortality rate Single centre retrospective Chylothorax rate (ligation and prospective cohort group vs. preservation group) study Level III Overall post-operative complication rate Overall post-operative mortality rate
2.1% vs 3.7% (p > 0.05) Not stated
653 patients who underwent transthoracic oesophagectomy were divided into 2 groups e 325 patients had thoracic duct ligation during surgery; 328 patients were in the preservation group
Single centre prospective RCT Level II
0.3% vs 2.1% (p [ 0.046) Not stated Not stated
Cagol et al., 2009 Italy
Lai et al., 2011 China
Bold signifies p values of less than 0.05.
Chylothorax rate (ligation group vs. preservation group) Overall complication rate Overall mortality rate
Not stated 0% vs 0.9% Not stated Not stated
REVIEW C.T.P. Choh et al. / International Journal of Surgery 10 (2012) 203e205
outcomes unrelated to chylothorax. They found an increased mortality rate and complication rate in the ligation group, but this was not statistically significant. Interestingly, they noted no advantage or detriment in long-term survival rates of patients who underwent ligation. It should be noted that Cagol et al.5 and Lai et al.7 stated their cohorts had no complications or deaths related to the process of ligation. However, they do not state the comparative morbidity or mortality rates of the two groups; hence their conclusions cannot be validated. Moreover on reviewing the evidence, there does not appear to be standard technique for thoracic duct ligation. For example, Cagol et al.5 described mass ligation using absorbable polyglactin, whilst Lai et al.7 also performed mass ligation using three non-absorbable sutures. In addition, there is to date no data on the efficacy of mass ligation versus formal identification and ligation (or indeed excision of a segment) of the thoracic duct. Finally there have been no studies comparing suture ligation with mechanical ligation or ligation using energy devices. There are a number of limitations in all of these studies which require discussion. For a start, there is some evidence to suggest that the site of the tumour has an impact on the incidence of chylothorax,6 and this may be a statistical confounder in analysing the results of all of these studies. Similarly, Bolgar et al.8 have suggested that histological type of the tumour and lymph node involvement may affect chylothorax rates, and these factors are further potential statistical confounders. In addition, there is some heterogeneity in the pre-operative management of the patients in these studies. For instance, in the study by Cagol et al.,5 half the patients received pre-operative chemoradiotherapy. More fundamentally, none of the papers had a standardized definition of what volume of chest drain output constitutes a post-operative chylothorax. Finally, with the exception of the paper by Fu et al.,4 there is no data on the overall complication, mortality, survival rate and the potential long-term oncological impact of ligating the thoracic duct. In summary, on reviewing the data, as the only prospective randomised controlled study with sizeable patient numbers demonstrated a significant decrease in post-operative chylothorax rates following intra-operative thoracic duct ligation, we concur with their conclusion that patients undergoing oesophagectomy should have prophylactic thoracic duct ligation. However, the impact of thoracic duct ligation on overall post-operative complications as well as long-term oncological outcomes have yet to be definitively assessed and proven. 8. Clinical bottom line For patients undergoing oesophagectomy, although there are conflicting results from retrospective studies, prospective
205
randomised controlled trial evidence points to prophylactic ligation of the thoracic duct as an effective measure to reduce the incidence of post-operative chylothorax.
Conflict of interest None declared.
Funding None declared.
Ethical approval None declared.
Author contribution Clarissa Cho - Literature search, analysis, writing Omar Khan - Analysis and editing of manuscript Igor J. Rychlik - Literature search, analysis and editing of manuscript Kieran McManus - Analysis and editing of manuscript
References 1. Khan OA, Dunning J, Parvaiz AC, Agha R, Rosin D, Mackway-Jones K. Towards evidence-based medicine in general surgical practice: best BETs. Int J Surg 2011;9:585e8. 2. Wemyss-Holden SA, Launois B, Maddern GJ. Management of thoracic duct injuries after oesophagectomy. Br J Surg 2001;88(11):1442e8. 3. Dougenis D, Walker WS, Cameron EW, Walbaum PR. Management of chylothorax complicating extensive oesophageal resection. Surg Gynecol Obstet 1992;174(6):501e6. 4. Cagol M, Ruol A, Castoro C, Alfieri R, Michieletto S, Ancona E. Prophylactic thoracic duct mass ligation prevents chylothorax after transthoracic oesophagectomy for cancer. World J Surg 2009;8:1684e6. 5. Lu JJ, Hou BP, Yao D, Zhang W, Qin CW, Ma J, et al. Effect of thoracic duct ligation during transthoracic oesophagectomy on the prevention of post-operative chylothorax in different tumour locations [Chinese]. Zhonghua Wei Chang Wai Ke Za Zhi 2008;11(1):36e8. 6. Fu JH, Hu Y, Huang WZ, Yang H, Zhu ZH, Zheng B. Evaluating prophylactic ligation of thoracic duct during radical resection of oesophageal carcinoma [Chinese]. Ai Zheng 2006;25(6):728e30. 7. Lai FC, Chen L, Tu YR, Lin M, Li X. Prevention of chylothorax complicating extensive oesophageal resection by mass ligation of thoracic duct: a random control study. Ann Thorac Surg 2011;91(6):1770e4. 8. Bolgar C, Walsh TN, Tanner NA, Keeling P, Hennessy TP. Chylothorax after oesophagectomy. Br J Surg 1991;78(5):587e8.