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Objective and Background: To determine the utility of positron emission tomography with CT (PET-CT) in the evaluation of non-small cell lung cancer (NSCLC) in an Asian context where tuberculosis rates are moderately high., Methods: Case records of consecutive patients with NSCLC undergoing PET-CT at the Singapore General Hospital over a 1-year period were retrospectively reviewed. The authors evaluated the sensitivity and specificity of PET-CT at their institution using surgical pathology or the tincture of time as the gold standard., Results: A total of 54 patients underwent PET-CT during this period. Seven patients were evaluated for solitary pulmonary nodule, for which PET-CT gave a sensitivity of 100% and specificity of 75%. There was one patient with false positive PET-CT due to active tuberculosis. In total, 41 patients underwent PET-CT for staging of NSCLC. There was one false positive (patient was found to have active tuberculous lymphadenitis) and one false negative for NSCLC. This gave a sensitivity of 92.3% and a specificity of 95%. Histology from the adrenal glands was available in two patients with PET-CT that was positive for adrenal metastases. One proved to be benign whereas the other was consistent with metastasis. Two patients had PET-CT positive for liver metastases, which was verified by histology. Two patients with positive PET-CT for lesions in the colon turned out to be benign histologically., Conclusions: Positron emission tomography with CT for the evaluation and follow-up of solitary pulmonary nodule and NSCLC can provide additional useful information to conventional radiology for treatment planning and a non-invasive determination of prognosis. However, physicians need to be aware of the limitations of this imaging modality, particularly when tuberculosis has a high prevalence in the population.

Introduction: F-18 fluorodeoxyglucose (FDG) combined positron emission tomography (PET)/ computed tomography (CT) imaging is often used in the surveillance of recurrent colorectal cancers after curative resections. We report 2 patients where FDG combined PET/CT imaging produced false positive results due to chronic inflammation and suture granuloma., Clinical Picture: Case 1 is a patient with a curative anterior resection done 10 months ago. Serial surveillance carcinoembryonic antigen (CEA) showed a marginal elevation. A solitary "hot spot" on combined PET/CT imaging was seen at the level of the previously resected inferior mesenteric vein. Case 2 is a patient with a positive solitary lesion on combined PET/CT imaging 16 months after a curative right hemicolectomy for colorectal cancer. The serum CEA was within normal limits., Treatment: Both patients had undergone exploratory laparotomy with complete resection of the solitary lesions., Outcome: The histology of Case 1 was reported as a suture granuloma while the histology of Case 2 was reported as an inflammatory nodule related to the previous suture pedicle, both with no malignant tissues identified., Conclusions: False positives on combined PET/CT imaging may result from inflammatory granulomas months after surgery.

Introduction: Hepatocellular carcinoma (HCC) is a common malignancy worldwide. Surgical resection is generally accepted as the first choice treatment of HCC. Many non-surgical techniques have been developed and used for the treatment of inoperable HCC, with limited efficacy. This paper studies the role of radionuclide therapy in the treatment of inoperable HCC and in an adjuvant setting following curative resection of HCC., Materials and Methods: Relevant articles published between 1980 and 2002 were reviewed. Articles were identified through a Medline search using the key words hepatocellular carcinoma, iodine-131 (I-131), lipiodol, yttrium-90 (Y-90), rhenium-188 (Re-188), monoclonal antibodies and anti-ferritin., Results: The objective response rate of patients with HCC treated with intra-arterial I-131 lipiodol was 40% to 70% and the median survival was between 6 and 9 months. The efficacy of I-131 lipiodol was similar to transarterial chemo-embolisation, but appears to be better tolerated by patients. A median survival of 9.4 months to 54 weeks was achieved using intra-arterial Y-90 microspheres for the treatment of HCC. Tumours in 4 patients became resectable after treatment. Re-188 lipiodol is a relatively new radiopharmaceutical used for the treatment of HCC. The results of a pilot study have shown Re-188 lipiodol to be a safe and cost-effective radiopharmaceutical for the treatment of HCC via the intra-arterial route. Its efficacy should be subjected to further evaluation. The use of radio-labelled monoclonal antibodies, such as anticarcinoembryonic antigen and antiferritin, for the treatment of HCC has yielded encouraging results but these forms of treatment are largely experimental and limited to a few centres. Intra-arterial treatment using I-131 lipiodol in an adjuvant setting for patients following curative resection of HCC has resulted in improved disease-free and overall survival. The 3-year survival for the treatment and control groups were 86.4% and 46.3%, respectively., Conclusion: Radionuclide therapy presents another interesting option for the treatment of HCC amidst the wide array of non-surgical modalities available.

Radioiodine, as a drug modality for the treatment of thyrotoxicosis, has been used in clinical practice for several decades. The physiologic basis, clinical indications and side-effects are discussed.

Introduction: In a minority of the cases, resection of hepatocellular carcinoma (HCC) is potentially curative but local recurrence is common. Adjuvant intra-arterial radio-conjugate therapy could potentially reduce the rate of local recurrence and increase disease-free and overall survival. However, in the majority of cases, treatment of HCC is largely palliative. A wide range of palliative treatment options are available and these include external radiation, hepatic intra-arterial chemo-embolisation, systemic chemotherapy and percutaneous ethanol injection. The long-term survival rate is poor. Hepatic intra-arterial radio-conjugate therapy provides a new and promising means of palliation., Materials and Methods: We share our initial experience in the treatment of patients with HCC. A total of 32 patients were recruited between October 1999 and June 2001. Group 1 comprised 15 patients who had potentially curative resection of HCC who were treated with Iodine-131 (I131) lipiodol as a form of adjuvant therapy. Group 2 comprised 17 patients with unresectable HCC, 12 of whom were treated with Yttrium-90 (Y90) microspheres and 5 with Rhenium-188 (Re188) lipiodol. The radio-conjugates were administered via the intra-arterial route., Results: Thirteen of the 15 patients in group 1 who were treated with I131 lipiodol following curative resection of HCC were free of disease, 1 patient died and 1 patient who developed recurrence was retreated with Re188 lipiodol and was subsequently free of disease. The 6-month disease-free survival rate was 100% and the 12-month disease-free and overall survival rates were 72% and 85%, respectively. Of the 12 patients in group 2 who were treated with Y90 microspheres for unresectable HCC, 6 had stable disease, 2 showed tumour regression and 4 died. The 6-month and 12-month survival rates were 75% and 66%, respectively. Of the 5 patients in group 2 who were treated with Re188 lipiodol for unresectable HCC, 4 had stable disease and 1 had regression of the right lobe tumour but progression of the left lobe tumour., Conclusion: Our results in the adjuvant treatment of patients with I131 lipiodol following curative resection of early HCC and in the palliative treatment of unresectable HCC using Y90 microspheres and Re188 lipiodol are preliminary and not fully conclusive. These preliminary results have to be confirmed in larger groups of patients and by prospective, randomised, controlled trials. This study highlights the preliminary experience in radionuclide therapy of HCC using hepatic intra-arterial radio-conjugates in a local context.