Résumé
Histiocytic sarcoma (HS) is an extremely rare and aggressive hematopoietic tumor. Although it can be seen at any anatomic location, the most common primary sites are skin as extranodal region, locations including the lymph nodes and gastrointestinal tract. To the best of our knowledge, in light of PubMed search, this is the first primary tonsillar HS case presented with disseminated metastases at the time of diagnosis. A 58-year-old male patient applied with swelling on the right side of the neck, difficulty in swallowing, and weight loss. Positron emission tomography computed tomography was performed and increased pathological 18F fluorodeoxy D glucose uptake was detected in the right palatine tonsil, bilateral cervical multiple lymph nodes, liver masses, intra abdominal lymph nodes, and nodular lesion in the left adrenal gland. Tonsillectomy was performed and the pathological result was reported as HS. The patient did not respond to any treatment and had died after 5 months from the date of diagnosis. In conclusion, HS is generally diagnosed at advanced stage, it has limited chemotherapy response and high mortality rates. To understand this rare disease's pathophysiological and clinical features, further investigations are needed
Résumé
PURPOSE: The aim of this study was to evaluate the role of whole body 18F-FDG PET/CT imaging in the detection of primary tumors in patients with a metastatic cancer from an unknown primary site. METHODS: The study population consisted of 43 patients with a biopsy proven metastatic disease, negative conventional diagnostic procedures (including CT/MRI/endoscopic procedures) and a whole body 18F-FDG PET/CT examination. Patients' records were retrospectively analyzed. According to the final pathologic diagnoses, rate of detection of the primary tumor site was determined. Additionally, overall patient survival was calculated to evaluate the prognostic value of 18F-FDG PET/CT findings. RESULTS: A primary tumor site was shown by 18F-FDG PET/CT in 24 patients (24/43; 55.8%). In 18 patients 18F-FDG PET/CT scans were negative (18/43; 41.8%). In a patient with an adenocarcinoma metastasis 18F-FDG PET/CT was falsely positive for an inflammatory lesion in the lung. Among the 18F-FDG PET/CT positive and negative groups median overall survival was not significantly different (log-rank p=0.573). CONCLUSION: Whole body 18F-FDG PET/CT imaging has a high rate of detection of a primary tumor in patients with a carcinoma of unknown origin.