Rong-Hsin Yang

Unusual site of metastasis detected with FDG PET/CT in a case of recurrent rectosigmoid cancer.

Metastatic colon cancers to the oral cavity are unusual, involving a majority of the mandible rather than the oral soft tissues. We describe a rare site of gingival metastasis in a case of rectosigmoid cancer. The patient was a 74-year-old woman who developed swelling and persistent bleeding of the right mandibular gingiva after tooth extraction. A PET/CT using 18F-FDG depicted multiple metastatic lesions in the neck, lung, abdominal wall, and mandibular gingiva. Histologic study of the gingival lesion confirmed the diagnosis of gingival metastasis from colon adenocarcinoma.

Zollinger-Ellison syndrome: Revelation of the gastrinoma triangle

Zollinger-Ellison syndrome is a complex condition in which one or more tumors form in the patients pancreas or upper duodenum. These tumors, called gastrinomas, secrete excessive amounts of gastrin, and almost all develop ulcers. The vast majority of gastrinomas are present within the “gastrinoma triangle,” which is composed of the porta hepatis, duodenal sweep, and pancreatic head. As surgery remains the treatment of choice, localization of the primary lesion is often challenging but essential. We present a 50-year-old man with a tentative diagnosis of Zollinger-Ellison syndrome. His In-111 pentetreotide scan, fused onto a Tc-99m abdomen image, revealed an avid lesion adjacent to the duodenal loop. Operative resection was performed, and a primary pancreatic gastrinoma was diagnosed by immunohistochemical staining. The neuroendocrine tumors have somatostatin receptors upon them. Therefore, a penteteotide scan, using In-111 radiolabelled somatostatin analogues, is the current technique of choice. This dual-isotope display permits a visual perception of anatomic landmarks around the lesion.

Bisphosphonate-related osteonecrosis of the jaw complicated by Ludwig's angina

Ludwigs angina is a life-threatening cellulitis that involves the submandibular and sublingual spaces. It often occurs after an infection of the roots of the teeth. However, modern dental care and use of antibiotics for oral infections have made Ludwigs angina rare. We present here a cancer patient exhibiting the sequential features of bisphosphonate related osteonecrosis of the jaw on bone scan complicating with Ludwigs angina. This report highlights the need for medical practitioners to be alert to these rare combinations in the compromised patient after bisphosphonate therapy. To the best of our knowledge, no case of Ludwigs angina secondary to osteonecrosis of the jaw has been reported.

Compartment syndrome following robotic-assisted prostatectomy: rhabdomyolysis in bone scintigraphy.

Major urologic surgery performed in the lithotomy position sometimes results in the serious complication of rhabdomyolysis. A 56-year-old man was admitted to the hospital for prostate adenocarcinoma. A whole-body bone scan was performed to exclude bony metastases, which demonstrated no bone lesions but showed intense soft-tissue activity in gluteus maximus muscles, findings suggestive of a myopathy. He had just undergone right nerve-sparing radical prostatectomy in the lithotomy position for 6 hours and presented with swollen bilateral thighs. Elevation of creatine kinase level confirmed muscle injury.

Hallucal sesamoiditis manifested on bone scan.

The first metatarsal articulation bears one third of the weight of the forefoot. The hallucal sesamoids are embedded in the flexor hallucis brevis and connected by the intersesamoid ligament and plantar plate. The sesamoid apparatus acts as a pulley to help pull the big toe down against the ground during walking. Repetitive pressure, force, or tension can cause sesamoiditis. If the impact is great enough, the bones can break. Here we present a woman with big toe pain during walking. Our case highlights the role of 99mTc-MDP bone scan in reaching the diagnosis of hallucal sesamoiditis.

Parkinsonism Secondary to Chronic Subdural Hematoma Showing in the TRODAT-1 Scanning

Chronic subdural haematoma (CSDH) is an encapsulated collection of old blood, mostly or totally liquefied and located between the dura mater and the arachnoid mater. A subdural hematoma can cause parkinsonian symptom as a result of compression on the mid-brain, but the actual cases are rarely reported. We herein reported a case of CSDH discovered incidentally by Tc-99m TRODAT-1 SPECT during a work-up for Parkinson’s disease. Surgical evacuation of the hematoma of this patient resulted in a partial recovery. This report recapped the multifaceted possibility of parkinsonism which necessitated a thorough and detailed assessment.

Unexpected thoracic endograft infection following a colorectal procedure

Infection of endovascular stent-grafts is a severe complication, but not often reported. We report herein a case of a 61-year-old man presented with pneumonia-like symptoms 24 days after receiving laparoscopic resection of stage 1 sigmoid cancer. Acute pneumonitis and cancer recurrence were excluded on Ga-67 citrate imaging. An infected endovascular graft of the aortic arch, which had been placed 4 months previously, was depicted scintigraphically. Due to multiple comorbidities, the patient underwent decortications via video-assisted thoracic surgery plus aggressive drainage. The symptoms settled and the patient was discharged on oral levofloxacin after intravenous treatment with ertapenem and teicoplanin for six weeks. This report fuels the belief that subclinical bacteremia associated with various procedures may incur bacterial seeding on the preexisting endovascular devices, and causes secondary prosthetic infection. In selected cases such as ours, prosthetic graft preservation may provide a definite treatment. Continued awareness of potential septic complications in patients treating with an endovascular grafting is needed. Correspondence to: Dr. Yum-Kung Chu, Department of Nuclear Medicine, Taipei Veterans General Hospital No. 201, Shipai Road Sec.2, Beitou District, Taipei City, Taiwan 11217, Tel: 886-2-28757301; Fax: 886-2-28715849; E-mail: ykchu@vghtpe.gov.tw

F-18 FDG Hypermetabolism Displaying Muscular Insult in Stiff-Person Syndrome: A Rare Case Report

Stiff-person syndrome (SPS) is a rare neuroimmunological disorder manifested through axial muscle spasms and different neuropathies, caused by the involuntary firing of motor units. This report focuses on a case of SPS in a female patient, who presented gait instability, episodic muscle spasms, and refractory epilepsy. Hypermetabolism of the insulted musculatures in the proximal limbs and axial muscles, was displayed on F-18 FDG PET/CT. The diagnosis of SPS was supported by an elevated level of anti-GAD (glutamic acid decarboxylase antibodies) in her serum and cerebrospinal fluid. The pathogenic role of autoimmunity in patients with status epilepticus should further be elucidated. The technology of PET/CT offer a unique opportunity in searching for the origin of epilepsy and the insulted musculatures.

Thymic Rebound Manifested on Various Scintigraphies: Case Series

The thymus is important for immunity because it produces T-cells. Various radiopharmaceuticals can localize to the thymus in physiologic or pathologic conditions. This report presents two cases of thymic rebound displayed on Ga-67 citrate and F-18 fluorodeoxy glucose studies.

Supernumerary breast masquerading as metastasis on serial 67Ga scan.

We report the incidental discovery of supernumerary breast changes on sequential ⁶⁷Ga scans in a woman with dermatofibrosarcoma protuberans excised 5 years before. The appearance of the accessory breast fluctuated with physiological ⁶⁷Ga uptake of the breast tissue was evident. Awareness of the concomitant changes in accessory breast with breast tissue could help narrow the differential diagnosis.