Paraconduit hernia is a relatively common long-term complication after esophagectomy for distal esophageal and gastroesophageal junction adenocarcinoma with an incidence of 8.1%. It can be repaired safely with laparoscopic approach in experienced centers, with a complication rate of 10% in our series. Neither sarcopenia nor muscle loss during treatments was correlated with paraconduit hernia formation in our series.
Patients with or without paraconduit hernia did not have differing skeletal muscle measurements before neoadjuvant treaments, preoperatively or after 6 months of follow-up, as seen in Table 5. Kaplan-Meier survival curves did not differ between the group who had less pronounced muscle loss between preneoadjuvant state and 6 months follow-up compared to those who had pronounced muscle loss during this time period. These results indicate that sarcopenia or progressing muscle loss are not related to paraconduit hernia formation. To our knowledge, this study is the first to examine this relationship. Previous studies have, however established a strong link with loss of muscle mass during neoadjuvant treatments, sarcopenia in general, and worsened overall survival.18–20
Preoperative radiotherapy was linked to a higher risk of paraconduit hernia, as has been seen in previous studies, which is logical as the effects radiation most likely weaken the crura and the crural repairs.12 A BMI under 25 was also associated with increased risk of paraconduit hernia, however this effect was not apparent after matching (Table 5), suggesting confounding variables to be responsible for this effect. Other factors, including hiatal hernia at the time of esophagectomy or stenting before esophagectomy were not associated with paraconduit hernia.
In our study, the incidence of paraconduit hernia (8.1%) is in line with previous reports.3,8 Rate of paraconduit hernia repair after MIE for esophageal or esophagogastric junction adenocarcinoma was 5.8% ,which is also similar to earlier reports.3,8,13 Laparoscopic repair was used in 90% of paraconduit hernia repair. Only one conversion to laparotomy was necessary, and this patient had peritoneal carcinosis and was in extremis from small bowel obstruction. Apart from the single patient whose prognosis was very grim related to the carcinomatosis of the peritoneal space, there were no mortality or complications related to the hernia repairs. In previous review by Oor et al, the pooled morbidity rate was 25% (range: 0% – 60%).15
The majority (71.4%, N = 10) of the paraconduit hernias in this study were diagnosed more than one year after the esophagectomy, and only one case within 3 months. To prevent early paraconduit hernia in our institution, the graft is sutured to the crura in addition to a hiatoplasty as needed. We believe that this prevents paraconduit hernia formation in the immediate postoperative period. However, no comparative data on the effect of this maneuver exists. In previous studies, the hernias that appeared early after esophagectomy were associated with high morbidity.29
The strength of this study was that even though it is a retrospective study, there was good follow-up data available due to standard follow-up protocols after esophagectomy for esophageal cancer. We also utilized propensity matching to somewhat diminish the potential biases that a retrospective study design inherently contains. Additionally, Finland has a centralized archive for medical records, so that data on complications can be achieved even if they are treated at another institution.
However, there are some limitations. There is a chance for selection and information bias. As esophageal cancer is a disease with high mortality, there is considerable mortality in follow-up. We included only patients with adenocarcinoma of the distal esophagus and gastroesophageal junction, who had received neoadjuvant therapy in order to maximize homogeneity. This means the results can not automatically be generalized to all esophagectomy patients.
According to our study, paraconduit hernia is a relatively common complication in patients undergoing minimally invasive esophagectomy for esophageal- or esophagogastric junction cancer after neoadjuvant treatments. However, no association between paraconduit hernia formation and sarcopenia or muscle mass loss during neoadjuvant treatments could be established.