INTRODUCTION: Extraskeletal chondrosarcomas are very rare tumors. Chondrosarcomas of skeletal origin generally arise in the pelvis, ribs, and shoulders of middle-aged and older adults. The chondrosarcomas found in the lungs are usually of metastatic origin from one of these skeletal primaries. Here, however, we describe a case of pulmonary chondrosarcoma metastatic from what seems to be a pleural primary.
CASE PRESENTATION: Our patient was a 73 year old female who initially presented to the hospital s/p colonoscopy during which she developed wheezing and respiratory distress. She was admitted to the hospital under the pulmonary service where a CXR revealed multiple bilateral pulmonary nodules, a 3cm left lower lobe lung mass and a large left-sided pleural effusion with marked left pleural thickening.A Thoracentesis and subsequent bronchoscopy failed to secure a diagnosis but because of the bloody appearance of the fluid and the radiologic findings noted above, we decided to proceed with a VATS +/- open lung biopsy to obtain tissue samples and perform a decortication.The initial thoracoscopy revealed extensive adhesions and an inability to document any intrathoracic structures as a result. As such a left thoracotomy was opted for. Innumerable pleural nodules were seen throughout the visceral and parietal pleura, as well as intraparenchymally. Pleural biopsies and wedge resection of the left lower lobe mass were obtained. Frozen sections on-site showed the possibility of a mesothelioma.Despite the original thought of likely adenocarcinoma, followed by suggestion of a mesothelioma, microscopic examination of the multiple fragments of lung and pleura revealed malignant appearing cells with moderate amounts of eosinophilic cytoplasm, nuclear pleomorphism and prominent nucleoli arranged primarily in small clusters and in cords. In the background, a large amount of myxoid/chondroid-like material surrounding these tumor cells was seen.Coupled with electron-microscopic analysis of the samples, a final diagnosis of chondrosarcoma was reached.
DISCUSSIONS: Although Skeletal chondrosarcomas commonly metastasize to the lungs, other primary sites have been described that may also metastasize there. These rarer primaries may include maxillary, sinus, trachea, and pleura. Primary chondrosarcomas of the lung parenchyma have also been described but with growth patterns reported to be that of an expanding, solitary, lobulated/well-circumscribed mass +/- significant invasion of the pulmonary arteries, pleura, pericardium and mediastinal lymph nodes.In general, chondrosarcomas have a slow and indolent course and if caught early enough patients may be amenable to local resection, although recurrences are common. Overall however there is no good treatment and patients tend to eventually succumb to their disease within a relatively short period of time.
CONCLUSION: Our patient likely has metastatic chondrosarcoma to the lung. The rarity of this case however is the likely primary site being the pleura itself. This is suggested by the multiple as opposed to solitary lesions seen in the lung parenchyma bilaterally and the malignant nature of the pleural pathology. This makes a pleural primary more likely than being simply local invasion of the pleura. The absence of extrathoracic and skeletal lesions makes this all the more likely. In conclusion, one must be open to all possibilities when evaluating a patient with findings attributable to more common diseases because, although rarer, the prognosis and approach to treatement may be markedly different, as in our patient who eventually opted to go to hospice rather than attempt any sort of treatment which in all likelihood would fail anyway and do more harm than good.Sometimes the hoofbeats really are zebras.
DISCLOSURE: Jamil Taji, No Financial Disclosure Information; No Product/Research Disclosure Information