Clinical Use of Lymphangiography for Intractable Spontaneous Chylothorax

Embolization of the thoracic duct in patients with iatrogenic chylothorax

Chylothorax is leakage of lymphatic fluid accumulating in the pleural cavity due to the thoracic duct's (TD) trauma or obstructions. It generally occurs as a traumatic complication after general thoracic surgery procedures (0.4%), especially after esophagectomy (4.7-8.6%). Traditionally, surgical intervention is performed if conservative management fails, but reports of high mortality (2.1%) and morbidity (38%) have led to the development of a minimally invasive percutaneous treatment method; TD embolization (TDE). The records of all patients treated for chylothorax with TDE from April 2015 to June 2019 were reviewed. Only patients with iatrogenic chylothorax were included. The outcomes measures are defined as a technical and a clinical success. A technical success, is defined as the ability to perform the embolization procedure, thereby injecting embolizing material Histoacryl with or without coils. A clinical success is defined as a complete cessation of lymphatic leakage into the pleural cavity without surgical intervention and, therefore, a cured patient. Lymphography was performed in all patients, and visualization of cisterna chyli was achieved in 14/17 patients (82.4%). Of the 17 patients included, 15 patients were successfully embolized and cured of chylothorax (88.2%). Successfully embolized patients had a median discharge time of 7 days. Most patients reported postprocedural pain, which was dealt with using conventional pain medication. TDE seems like a safe percutaneous treatment technique with a high clinical success rate in iatrogenic chylothorax patients which can be readily implemented if the clinical experience is available..

Lymphatic Interventions for Chylothorax: A Systematic Review and Meta-Analysis

PURPOSE

To perform a systematic review and meta-analysis of published studies to evaluate the efficacy of lymphatic interventions for chylothorax.

MATERIALS AND METHODS

The MEDLINE, EMBASE, and Cochrane databases were searched for English-language studies until March 2017 that included patients with chylothorax treated with lymphangiography (LAG), thoracic duct embolization (TDE), or thoracic duct disruption (TDD). Exclusion criteria were as follows: a sample size of less than 10 patients, no extractable data, or data included in subsequent articles or duplicate reports.

RESULTS

The cases of 407 patients from 9 studies were evaluated. The pooled technical success rates of LAG and TDE were 94.2% (95% confidence interval [CI], 88.4%-97.2%; I² = 46.7%) and 63.1% (95% CI, 55.4%-70.2%; I² = 37.3%), respectively. The pooled clinical success rates of LAG, TDE, and TDD, on a per-protocol basis, were 56.6% (95% CI, 45.4%-67.2%; I² = 5.4%), 79.4% (95% CI, 64.8%-89.0%; I² = 68.1%), and 60.8% (95% CI, 49.4%-71.2%; I² = 0%), respectively. The pooled major complication rate of LAG and TDE was 1.9% (95% CI, 0.8%-4.3%; I² = 0%) and 2.4% (95% CI, 0.9%-6.6%; I² = 26.4%), respectively. The pooled overall clinical success rate of lymphatic interventions, on an intention-to-treat basis, was 60.1% (95% CI, 52.1%-67.7%; I² = 54.3%). Etiology of chylothorax was identified as a significant source of heterogeneity for the pooled clinical success rate of TDE and overall clinical success rate.

CONCLUSIONS

Lymphatic interventions have a respectable efficacy for the treatment of chylothorax.

The changing management of chylothorax in the modern era

Initial conservative therapy is applied to all cases of chylothorax (CTx) with expected excellent outcomes. The indication for aggressive surgical treatment of early CTx remains uncertain and requires rigorous scientific scrutiny. Lymphangiography and lymphoscintigraphy are useful to localize the leak and assess thoracic duct patency as well as to differentiate partial from complete thoracic duct transection. The aetiology of the CTx, flow rate and patient condition dictate the preferred management. Octreotide/somatostatin and etilefrine therapy is highly efficacious in the conservative management of CTx. For patients in whom conservative management fails, those who are good surgical candidates, and those in whom the site of the leak is well identified, surgical repair and/or ligation using minimally invasive techniques is highly successful with limited adverse outcomes. Similarly, if the site of the chylous effusion cannot be well visualized, a thoracic duct ligation via video-assisted thoracic surgery is the gold standard approach. A pleuroperitoneal or less often a pleurovenous shunt is a final option and may be curative in some patients.

Radiotherapy in the treatment of postoperative chylothorax

Background

Chylothorax is characterized by the presence of chyle in the pleural cavity. The healing rate of non-operative treatment varies enormously; the maximum success rate in series is 70%. We investigate the efficacy and outcomes of radiotherapy for postoperative chylothorax.

Methods

Chylothorax was identified based on the quantity and quality of the drainage fluid. Radiation was indicated if the daily chyle flow exceeded 450 ml after complete cessation of oral intake. Radiotherapy consisted of opposed isocentric portals to the mediastinum using 15 MV photon beams from a linear accelerator, a single dose of 1–1.5 Gy, and a maximum of five fractions per week. The radiation target area was the anatomical region between TH3 and TH10 depending on the localization of the resected lobe. The mean doses of the ionizing energy was 8.5 Gy ± 3.5 Gy.

Results

The median start date of the radiation was the fourth day after chylothorax diagnosis. The patients’ mediastinum was radiated an average of six times. Radiotherapy, in combination with dietary restrictions, was successful in all patients. The median time between the end of the radiation and the removal of the chest tube was one day. One patient underwent wound healing by secondary intention. The median time between the end of radiation and discharge was three days, and the overall hospital stay between the chylothorax diagnosis and discharge was 18 days (range: 11–30 days). After a follow-up of six months, no patient experienced chylothorax recurrence.

Conclusions

Our results suggest that radiotherapy in combination with dietary restriction in the treatment of postoperative chylothorax is very safe, rapid and successful. This novel interventional procedure can obviate repeat major thoracic surgery and shorten hospital stays and could be the first choice in the treatment of postthoracotomy chylothorax.