Keywords
thoracic surgery - chest wall - thoracoscopy/VATS
Background
Peripheral neurogenic tumors originating from the intercostal nerves are extremely rare. The incidence is below 10% of all primary neurogenic thoracic tumors.[1] These neurogenic tumors can be either benign or malignant. They include heterogeneous types of tumors such as fibromas, malignant neurilemmomas, paraganglionic tumors, and primitive neuroectodermal tumors. These tumors are often entirely asymptomatic and are discovered incidentally during imaging of the thorax for other reasons. In the present case, the patient had symptoms and was found to have two synchronous intercostal neurinomas.
Discussion
Chronic band-shaped thoracic pain can have various causes. In the absence of trauma, thoracic disk prolapse with compression of the spinal nerves is the most frequent cause of such symptoms. Neoplastic changes on the intercostal nerves are extremely rare. In a retrospective analysis of 149 intrathoracic neurogenic tumors,[2] the incidence was 3%. Thoracic pain is the leading symptomatic which gives cause of further diagnostics. These tumors form a heterogeneous group consisting of neurofibromas, schwannomas, paragangliomas, and malignant neurilemmomas. Only approximately 20 case reports are published in the literature.[1] Usually in a computed tomographic (CT) scan of the thorax, a solid or more cystic lesion in the intercostal space is seen. In this situation, a MRI of the thorax may be helpful for checking for a chest wall infiltration. In this case, only one small cystic change was apparent in the region of one intercostal nerve. When planning surgery, it is always necessary to establish whether the spinal canal is also affected. This was not the case in our patient. A CT-controlled fine needle biopsy can be useful to get an idea which type of tumor is present. In the literature, there were no alternative treatment options, for example, like ethanol injections or radiofrequency ablation described, the only treatment option is radical surgery. In our case, we decided to do a video thoracoscopy. It can be helpful for further diagnostic workup and treatment.[3] The extension and precise location of the pathology can be established with this procedure and the tumor can be removed completely during the same session, as in our case.[4] Morbidity is low in video-assisted thoracoscopic tumor resection.[5] However, it is often impossible to separate the neurinoma from the intercostal nerve so that complete resection of the intercostal nerves is necessary as in this case. A neural cyst was also present in our case. It is interesting that two neurinomas occurred at the same time on two different intercostal nerves. Up to now, several schwannomas along one intercostal nerve have been described.[6] However, if the tumor is greater than 5 cm,[2] the risk for malignancy increases or there is a histological proof for malignancy, and only local removal of the tumor is not sufficient. The chest wall needs to be resected as well[1] to prevent local recurrence. If the tumor is histologically benign, follow-up is not necessary because the long-term prognosis is very good. Local recurrence has not been reported for neurinomas. Our patient was free from symptoms immediately after the operation. Pain medication was no longer given.
