The thoracic cavity has complex networks of lymphatics which have a fundamental immunological function protecting intrathoracic organs such as the lungs, pleura, oesophagus and mediastinum. These networks drain interstitial fluid from the lungs, chyle from the gastrointestinal tract, and white blood cells and other immune components (Brotons et al., 2012). Thoracic lymphatics are involved in several diseases that most thoracic surgeons are concerned about. The most important pathologies affecting thoracic lymphatics are cancers spreading from intrathoracic organs. As lymphatic involvement by cancerous cells guide tumour staging, prognosis and management (Brotons et al., 2012), it is crucial to have a good understanding of thoracic …show more content…
The subpleural lymphatics run beneath the lung surface, mostly over the lower lobes, toward the hilum in order to anastomose with the lymphatics of the deep plexus there (Schraufnagel, 2010). While the superficial plexus drains the visceral pleura and adjacent layer of subpleural tissues the remaining parts of the lung is drained by the deep plexus (Brotons et al., 2012). The subpleural lymphatics were occasionally found to have direct passages to the mediastinal nodes (Riquet et al., 1989), which explains the occurrence of skipped metastasis in around 15% of primary lung cancer cases.
The deep plexus consists of lymphatic capillaries which fuse forming lymphatic collecting vessels known as the collectors, which have unidirectional valves. Large lymphatic collectors have 3 distinctive layers: an intima with a lymphatic endothelium and a continuous basal membrane, a media with a second valve system, and an adventitia composed of collagen and fibroblast bundles (Schmid-Schonbein, …show more content…
In a recent study, after reviewing a big sample of 1779 lobectomized patients and analysing their pathological characteristics based on tumour location, it was concluded that the nodal metastasis pattern cannot be predicted depending on tumour location. Therefore, in surgical management of nonsmall cell lung cancer (NSCLC), complete systematic mediastinal lymph node dissection remains the best option from an oncological perspective. Even though, in the same study 90% of cases with right lower lobe tumours were found to have metastases to the inferior mediastinum (Ndiaye et al.,