It may be difficult to differentiate an infectious versus a malignant process when a mass is discovered on chest x-ray. History, physical examination, and laboratory are used in the decision-making process. If serial radiographic examinations are available, doubling time of the lesion can be useful in determining the etiology. It is generally believed that a lesion which doubles faster than every 30 days represents a benign process (1).
A 49-year-old male was admitted for evaluation of fevers and chills of two weeks’ duration. He reported recent onset of scant hemoptysis and a ten-pound weight loss. Physical examination was significant for a temperature of 102 degrees Fahrenheit and expiratory wheezing. Laboratory revealed a white blood cell count of 23,500/cm3. Chest x-ray and CT revealed an 8.5 cm mass-like density in the anterior segment of the right upper lobe. The patient was treated with amoxicillin/clavulanate and improved clinically within 48 hours. He underwent bronchoscopy which revealed purulent drainage from the right upper lobe. There were no endobronchial lesions. Transbronchial biopsies revealed inflammatory tissue with fibrosis. Due to his clinical improvement, a decision was made to treat the patient with a prolonged course of antibiotics for a lung abscess. The patient was seen 4 weeks post-discharge and had inadvertently received only one week of antibiotics. The mass had enlarged to 11cm and his white blood cell count had increased to 39,500/cm3. A pigtail catheter was placed and drained 10 cc of non-diagnostic material. His white count continued to rise and the patient underwent surgical resection. Pathology revealed giant cell carcinoma. A CT scan of the head (compared to a study obtained for trauma two months prior to admission) revealed multiple new metastatic lesions.
Giant cell carcinoma of the lung is a malignant, aggressive, and rare neoplasm. Radiographic features are peripheral, round or oval, and without lobulation or cavitation. Histologically it is classified as a subtype of large cell undifferentiated carcinoma by the World Health Organization. The tumor contains highly pleomorphic, often multinucleated, tumor giant cells. It must contain at least 40% giant cells that are greater than 40μm to make a diagnosis.We report a case of giant cell carcinoma which was very aggressive. Initial bronchoscopy and clinical features favored an infectious etiology; however, his tumor doubled in size within 4 weeks and metastasized to his brain while he received treatment for a presumed lung abscess. A Japanese study showed giant cell carcinoma to have the fastest doubling time of all lung cancers at 67.5 days (2). Rapid growth with early hematogenous spread occurs frequently (3).Effective therapy for this tumor is difficult to determine due to the lack of controlled trials. Resection and radiation have been suggested to prolong survival time; however, one series found the average survival time was 7.4 months from the time of initial symptoms, and only 4.2 months from the time of diagnosis (4).
Although fever, chills, leukocytosis, and rapid expansion of a pulmonary lesion are suggestive of an infectious process, giant cell carcinoma of the lung should be considered in the differential diagnosis. Delay in diagnosis may result in a poor outcome with this aggressive tumor.
Douglas Fiedler, None.