Combined use of preoperative 18F FDG-PET imaging and intraoperative gamma probe detection for accurate assessment of tumor recurrence in patients with colorectal cancer

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to combine intraoperative gamma probe (GP) detection with preoperative fluorine 18-fluoro-2-deoxy-glucose positron emission tomography (¹⁸F FDG-PET) imaging in order to improve detection of tumor recurrence in colorectal cancer (CRC) patients.</p> <p>Methods</p> <p>Twenty-one patients (12 females, 9 males) with a mean age of 54 years (range 31–78) were enrolled. Patients were suspected to have recurrent CRC by elevated CEA (n = 11), suspicious CT findings (n = 1), and clinically suspicious findings (n = 9). Preoperative FDG-PET scan and intraoperative GP study were performed in all patients. Mean time interval between preoperative FDG-PET scan and surgery was 16 days (range 1–41 days) in 19 patients. For intraoperative GP studies, 19 patients were injected with a dose of 10–15 mCi ¹⁸F FDG at approximately 30 minutes before the planned surgery time. In two patients, the intraoperative GP study was performed immediately after preoperative FDG-PET scan.</p> <p>Results</p> <p>Preoperative FDG-PET and intraoperative GP detected 48 and 45 lesions, respectively. A total of 50 presumed site of recurrent disease from 20 patients were resected. Thirty-seven of 50 presumed sites of recurrent disease were histological-proven tumor positive and 13 of 50 presumed sites of recurrent disease were histological-proven tumor negative. When correlated with final histopathology, the number of true positive lesions and false positive lesions by preoperative FDG-PET and intraoperative GP were 31/9 and 35/8, respectively. Both preoperative FDG-PET and intraoperative GP were true positive in 29 lesions. Intraoperative GP detected additional small lesions in the omentum and pelvis which were not seen on preoperative FDG-PET scan. FDG-PET scan demonstrated additional liver metastases which were not detected by intraoperative GP. Preoperative FDG-PET detected distant metastasis in the lung in one patient. The estimated radiation dose received by a surgeon during a single 18F FDG GP surgery was below the occupational limit.</p> <p>Conclusion</p> <p>The combined use of preoperative FDG-PET and intraoperative GP is potentially helpful to the surgeon as a roadmap for accurately locating and determining the extent of tumor recurrence in patients with CRC. While intraoperative GP appears to be more sensitive in detecting the extent of abdominal and pelvic recurrence, preoperative FDG-PET appears to be more sensitive in detecting liver metastases. FDG-PET is also a valuable method in detecting distant metastases.</p

Combined approach of perioperative 18F-FDG PET/CT imaging and intraoperative 18F-FDG handheld gamma probe detection for tumor localization and verification of complete tumor resection in breast cancer

<p>Abstract</p> <p>Background</p> <p>¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) has become an established method for detecting hypermetabolic sites of known and occult disease and is widely used in oncology surgical planning. Intraoperatively, it is often difficult to localize tumors and verify complete resection of tumors that have been previously detected on diagnostic PET/CT at the time of the original evaluation of the cancer patient. Therefore, we propose an innovative approach for intraoperative tumor localization and verification of complete tumor resection utilizing ¹⁸F-FDG for perioperative PET/CT imaging and intraoperative gamma probe detection.</p> <p>Methods</p> <p>Two breast cancer patients were evaluated. ¹⁸F-FDG was administered and PET/CT was acquired immediately prior to surgery. Intraoperatively, tumors were localized and resected with the assistance of a handheld gamma probe. Resected tumors were scanned with specimen PET/CT prior to pathologic processing. Shortly after the surgical procedure, patients were re-imaged with PET/CT utilizing the same preoperatively administered ¹⁸F-FDG dose.</p> <p>Results</p> <p>One patient had primary carcinoma of breast and a metastatic axillary lymph node. The second patient had a solitary metastatic liver lesion. In both cases, preoperative PET/CT verified these findings and demonstrated no additional suspicious hypermetabolic lesions. Furthermore, intraoperative gamma probe detection, specimen PET/CT, and postoperative PET/CT verified complete resection of the hypermetabolic lesions.</p> <p>Conclusion</p> <p>Immediate preoperative and postoperative PET/CT imaging, utilizing the same ¹⁸F-FDG injection dose, is feasible and image quality is acceptable. Such perioperative PET/CT imaging, along with intraoperative gamma probe detection and specimen PET/CT, can be used to verify complete tumor resection. This innovative approach demonstrates promise for assisting the oncologic surgeon in localizing and verifying resection of ¹⁸F-FDG positive tumors and may ultimately positively impact upon long-term patient outcomes.</p

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology

Real-Time Scintigraphic Assessment of Intravenous Radium-223 Administration for Quality Control

Radium-223 (223Ra) dichloride is an approved intravenous radiotherapy for patients with osseous metastases from castration-resistant prostate cancer (CRPC). In addition to the therapeutic alpha radiation, there is additional 223Ra radiation generated which produces photons that can be imaged with conventional gamma cameras. No studies have evaluated real-time and quality imaging during intravenous 223Ra administration to verify systemic circulation and exclude 223Ra extravasation at the injection site. A retrospective review was performed for fifteen 223Ra administrations for CRPC patients which were imaged using a large field of view portable gamma camera (LFOVPGC) for the purposes of quality control and patient safety. Dynamic imaging of the chest was performed before, during, and after the 223Ra administration to verify systemic circulation, per institutional clinical protocol. Before and after 223Ra administration, a static image was obtained of the intravenous access site. Dynamic imaging of the chest confirmed systemic administration early during the 1-minute injection period for all patients. There were no cases of focal 223Ra extravasation at the site of intravenous access. These results verify that systemic 223Ra administrations can be quantified with real-time imaging using an LFOVPGC. This simple approach can confirm and quantify systemic circulation of 223Ra early during injection and exclude focal extravasation for the purposes of quality control

Functional correction of neurological and somatic disorders at later stages of disease in MPS IIIA mice by systemic scAAV9-hSGSH gene delivery

The reversibility of neuropathic lysosomal storage diseases, including MPS IIIA, is a major goal in therapeutic development, due to typically late diagnoses and a large population of untreated patients. We used self-complementary adeno-associated virus (scAAV) serotype 9 vector expressing human N-sulfoglucosamine sulfohydrolase (SGSH) to test the efficacy of treatment at later stages of the disease. We treated MPS IIIA mice at 1, 2, 3, 6, and 9 months of age with an intravenous injection of scAAV9-U1a-hSGSH vector, leading to restoration of SGSH activity and reduction of glycosaminoglycans (GAG) throughout the central nervous system (CNS) and somatic tissues at a dose of 5E12 vg/kg. Treatment up to 3 months age improved learning ability in the Morris water maze at 7.5 months, and lifespan was normalized. In mice treated at 6 months age, behavioral performance was impaired at 7.5 months, but did not decline further when retested at 12 months, and lifespan was increased, but not normalized. Treatment at 9 months did not increase life-span, though the GAG storage pathology in the CNS was improved. The study suggests that there is potential for gene therapy intervention in MPS IIIA at intermediate stages of the disease, and extends the clinical relevance of our systemic scAAV9-hSGSH gene delivery approach

Digital photograph of the resected liver tissue specimen (A) and maximum intensity projection from the specimen PET scan (B)

<p><b>Copyright information:</b></p><p>Taken from "Combined approach of perioperative F-FDG PET/CT imaging and intraoperative F-FDG handheld gamma probe detection for tumor localization and verification of complete tumor resection in breast cancer"</p><p>http://www.wjso.com/content/5/1/143</p><p>World Journal of Surgical Oncology 2007;5():143-143.</p><p>Published online 21 Dec 2007</p><p>PMCID:PMC2235860.</p><p></p> Postoperative PET maximum intensity projection in the anterior projection view of the lower chest and upper abdomen demonstrating that there is no longer a hypermetabolic focus in the region of the liver (C)

Preoperative PET maximum intensity projection in the lateral projection view (A) and cross sectional fused PET/CT images (B)

<p><b>Copyright information:</b></p><p>Taken from "Combined approach of perioperative F-FDG PET/CT imaging and intraoperative F-FDG handheld gamma probe detection for tumor localization and verification of complete tumor resection in breast cancer"</p><p>http://www.wjso.com/content/5/1/143</p><p>World Journal of Surgical Oncology 2007;5():143-143.</p><p>Published online 21 Dec 2007</p><p>PMCID:PMC2235860.</p><p></p> The preoperative PET/CT scan revealed two hypermetabolic foci, representing the left breast primary tumor and the solitary left axillary metastasis