Comparison between 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography and positron emission tomography/computed tomography hardware fusion for staging of patients with lymphoma.

PURPOSE: 2-Deoxy-2-[18F]fluoro-D-Glucose positron emission tomography (FDG-PET) stages patients with Hodgkin's disease (HD) and Non-Hodgkin's lymphoma (NHL) with higher accuracy than computed tomography (CT). We sought to determine whether integrated (hardware) fused PET/CT imaging results in further improvements in staging accuracy. PROCEDURES: Seventy-three patients (age 51 +/- 17 years, 37 female, 36 male) with HD (n = 20) or NHL (n = 53) undergoing staging were studied with an integrated PET/CT system. Image findings were verified by clinical follow up, additional imaging and when available, histology. RESULTS: Thirty-four of 73 patients (46.5%) had evidence of disease and 39 were disease free as confirmed by clinical evaluation and follow-up for 41 +/- 22 weeks (n = 73), including biopsy (n = 26), and other imaging modalities (n = 52) when available. A discordant image interpretation between PET and PET/CT occurred in seven patients (10%). PET/CT correctly upstaged two and downstaged five patients. Overall staging was accurate in 93% with PET/CT and 84% with PET (P = 0.03). CONCLUSION: Lymphoma is staged with higher accuracy using PET/CT than PET alone.     

Comparison of CT, PET, and PET/CT for Staging of Patients with Indolent Non-Hodgkin’s Lymphoma

Purpose  The aim was to investigate the potential impact of positron emission tomography (PET)/computed tomography (CT) as compared to PET and CT on the staging of patients with indolent lymphoma. Procedures  PET/CTs from 45 patients with indolent lymphoma undergoing staging or restaging were studied. Clinical follow-up, additional imaging, and histology served as the gold standard. Results  PET/CT correctly diagnosed 92 nodal regions as positive for lymphomatous involvement and 458 as disease free vs 68 and 449 for PET and 64 and 459 for CT, respectively. The respective sensitivities, specificities, and accuracies were 99%, 100%, and 99.8% for PET/CT, 68%, 97.5%, and 92.2% for PET, and 70%, 100%, and 94.7% for CT. PET/CT performed significantly better than PET (p < 0.001 for sensitivity, specificity, and accuracy) and CT (p < 0.001 for sensitivity and accuracy). PET/CT also correctly identified significantly more extra-nodal lesions (22) than CT (14) and PET (nine). Conclusions  PET/CT provides significantly more accurate information compared to PET and CT for the staging and re-staging of patients with indolent lymphoma.     

Staging of peritoneal carcinomatosis: enhanced CT vs. PET/CT

Purpose To assess and compare the performance of CT and 18F-FDG-PET/CT in the evaluation of peritoneal carcinomatosis (PC). Method and materials Thirty consecutive patients with PC and scheduled for a surgery underwent a CT of the abdomen and pelvis and a whole-body 18F-FDG PET/CT. The extent of PC was assessed precisely using the peritoneal cancer index combining the distribution of tumor throughout 11 abdominopelvic regions with a lesion size score. CT and PET/CT imaging results were compared in all patients with intraoperative findings using an interclass correlation test. Results The presence of PC was correctly determined on CT and PET/CT in 23/28 and 16/28 patients, respectively. The extent of PC was understaged with CT and PET/CT in 27 patients and overstaged with CT and PET/CT in 1 and 2 patients, respectively. The interclass correlation was 0.53 (moderate) between CT and surgery and 0.12 (low) between PET/CT and surgery. The interclass correlation was higher for mucinous tumor (0.63) than for non-mucinous (0.16) on CT imaging whereas no difference was found in PET/CT. Conclusion The intraperitoneal assessment of the extent of carcinomatosis, necessary to assess prognosis and treatment planning, is not accurate enough with CT and PET/CT imaging.     

Positron emission tomography with 2-deoxy-2-[(18)F]fluoro-D-glucose for evaluating local and distant disease in patients with cervical cancer.

PURPOSE: To assess the accuracy of positron emission tomography (PET) with 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) for evaluating local and distant disease in patients with cervical cancer. METHODS: The PET imaging database maintained at our institution was used to identify patients who received FDG-PET scans for the clinical indication of cervical cancer for the past four years. Patients were followed for a minimum of six months following the PET study. Results of the FDG-PET studies were correlated with surgical pathology, biopsy results, and/or clinical follow up to assess the accuracy of FDG-PET in evaluating local and distant disease. RESULTS: A total of 61 FDG-PET studies performed in 41 patients were included in this retrospective study. Nine FDG-PET studies were performed for initial staging of cervical cancer, and 52 PET scans were performed in 35 different patients as restaging studies following therapy. For the initial staging, the local primary disease was identified in all nine FDG-PET studies, and PET distinguished the patients which had localized disease (four patients) from those with distant metastases on follow-up (five patients) with 100% accuracy. For restaging cervical cancer, FDG-PET had a sensitivity of 0.82 and specificity of 0.97 (accuracy 0.92) for evaluation of local recurrence. For evaluating distant disease in these patients, PET had a sensitivity of 1.00 and specificity of 0.90 (accuracy 0.94). In the evaluation of local disease, focal rectal activity caused false-positive results in two cases. Three false-positive studies for distant disease were caused by inflammatory adenopathy. CONCLUSION: FDG-PET is an accurate modality both for initial staging and restaging of patients with cervical cancer. PET is particularly sensitive for detecting distant metastases, allowing stratification of patients into those with locally confined disease and those with distant disease. These results were achieved by using a standardized PET imaging protocol without the use of bowel preparations, lasix administration, or Foley catheter drainage. Evaluation of local disease can be challenging due to adjacent rectal and bladder activity, and the use of hybrid PET/computed tomography (CT) scanners in the future may further improve evaluation of local disease.     

Spectrum of PET–CT pelvic pitfalls in patients with gynecologic malignancies

Integrated positron emission tomography?Ccomputed tomography (PET?CCT) represents a major technologic advance in oncologic imaging of patients with gynecologic malignancies, since it improves localization of regions of increased 18F-fluorodeoxyglucose (FDG) uptake and staging/restaging accuracy by allowing a near-simultaneous acquisition of co-registered, spatially matched metabolic and anatomic data in the same examination. However, physiologic processes, normal variants, and many benign lesions within the pelvis can accumulate FDG and may be confused with malignant neoplasms. Conversely, false-negative results due to malignancies with low FDG uptake can pose a diagnostic challenge in patients with gynecologic cancer. With the increased use of PET?CCT in patients with gynecologic malignancies, misinterpretation of these potential pitfalls can have significant implications and alter staging/restaging and patient management. In this article, we review these potential pitfalls in integrated PET?CCT of the pelvis in patients with gynecologic cancer.     

Utility of sonographically guided biopsy in metabolically suspected recurrent lymphoma.

OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of sonographically guided biopsy of [(18)F]fluorodeoxyglucose (FDG)-avid foci on positron emission tomography (PET)/computed tomography (CT) in patients with lymphoma. METHODS: We retrospectively reviewed the medical records of 56 patients with lymphoma (25 male and 31 female; mean age, 48.5 years; range, 22-80 years) who underwent sonographically guided biopsy of hypermetabolic FDG-avid foci precisely localized by PET/CT. Biopsies were performed up to 3 months after PET/CT. The accuracy of core biopsy was calculated and compared with clinical follow-up and histopathologic results of open biopsy. RESULTS: Sixty-six sonographically guided biopsies were performed in the 56 patients. Histopathologic results were conclusive in 53 (80%) of 66. No complications occurred during or after the procedure. The overall sensitivity, specificity, positive predictive value, and accuracy for diagnosis of lymphoma were 100%, 95%, 97%, and 98%, respectively. CONCLUSIONS: Sonographically guided biopsy is a safe and effective means for investigating metabolically active lesions on FDG-PET/CT in patients with known lymphoma.     

2-Deoxy-2-[F-18]fluoro-<Emphasis Type="SmallCaps">d</Emphasis>-glucose Positron Emission Tomography/Computed Tomography in the Management of Melanoma

Objectives 2-Deoxy-2-[F-18]fluoro-d-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) is widely available as a powerful imaging modality, combining the ability to detect active metabolic processes and their morphologic features in a single exam. The role of FDG-PET is proven in a variety of cancers, including melanoma, but the estimates of sensitivity and specificity are based in the majority of the published studies on dedicated PET, not PET/CT. Therefore, we were prompted to review our experience with FDG-PET/CT in the management of melanoma. Methods This is a retrospective study on 106 patients with melanoma (20–87 years old; average: 56.8 ± 15.9), who had whole-body FDG-PET/CT at our institution from January 2003 to June 2005. Thirty-eight patients (35.9%) were women and 68 patients (64.1%) were men. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed. Results All patients had the study for disease restaging. The primary tumor depth (Breslow’s thickness) at initial diagnosis was available for 76 patients (71.7%) and ranged from 0.4 to 25 mm (average: 3.56 mm). The anatomic level of invasion in the skin (Clark’s level) was determined for 70 patients (66%): 3, level II; 13, level III; 43, level IV; 11, level V. The administered dose of ¹⁸F FDG ranged from 9.8 to 21.6 mCi (average: 15.4 ± 1.8 mCi). FDG-PET/CT had a sensitivity of 89.3% [95% confidence interval (CI): 78.5–95] and a specificity of 88% (95% CI: 76.2–94.4) for melanoma detection. Conclusion This study confirms the good results of FDG-PET/CT for residual/recurrent melanoma detection, as well as for distant metastases localization. PET/CT should be an integral part in evaluation of patients with high-risk melanoma, prior to selection of the most appropriate therapy.     

Restaging after neoadjuvant chemoradiotherapy for rectal adenocarcinoma: role of F18-FDG PET.

Multimodality treatment of loco-regional advanced rectal cancer has demonstrated to improve local control and overall survival. Proctoscopy, digital rectal examination (DRE), computer tomography (CT), endorectal ultrasound (ERUS), and magnetic resonance imaging (MRI) cannot correctly detect downstaging in rectal tumors after chemo radiation therapy (CRT). New imaging techniques, like 18F-FDG PET, may play some role in predicting the pathologic response to CRT before surgical resection. Aim of the present study was to further investigate the accuracy and predictive value of 18F-FDG PET in a large series of patients with rectal cancer treated with preoperative intensified CRT. Between January 2000 and December 2003, 81 patients with histologically proven adenocarcinoma in clinical stage II-III disease, according to criteria of TNM classification, were included in this study. All patients were submitted to diagnostic staging workup with DRE, proctoscopy with biopsy, ERUS, CT scan of the abdomen and pelvis or pelvic MRI plus liver ultrasonography, coloscopy or barium colonic enema. One month later the end of CRT all patients were submitted to diagnostic restaging work-up (DRW) and 18F-FDG PET. Surgery was performed 8-9 weeks after the end of CRT and pathologic stage was defined. Moreover a pathologic assessment of tumor regression was made with tumor regression grade score (TRG). PET correctly identified 22/28 (79% specificity) patients with complete pathologic response (pCR). However, sensitivity was 45% (24/53) while PPV, and NPV were equal to 77 and 43%, respectively. Total PET accuracy rate was 56%. PET sensitivity increased from 45 to 56% if the end-point was pCR, or TRG score, respectively. The best correlation was found between PET findings and pathologic stage (P <0.01) or TRG score (P <0.01). The accurate identification of rectal cancer patients with major pathological response after preoperative CRT further supports the necessity of designing prospective studies with new and more accurate was imaging technologies with the main object of offering conservative treatment in responder patients.     

18F-NaF PET/CT 显像与99mTc-MDP SPECT 骨显像对乳腺癌患者骨转移诊断的对比研究

目的:探讨18F-NaF PET/CT显像与99mTc-MDP SPECT显像对乳腺癌患者骨转移的诊断价值.方法:回顾性分析2017年12月-2019年6月间我院收治的乳腺癌患者35例.所有患者均在2周内行18F-NaF PET/CT显像与99mTc-MDP SPECT显像,以病理结果、X线、CT、MRI、临床随访等综...     

Clinical application of 18F‐fluoro‐2‐deoxy‐D‐glucose positron emission tomography/computed tomography in breast cancer

Positron emission tomography (PET)/computed tomography (CT) is not suited for primary diagnostics of breast tumours and it cannot replace sentinel lymph node technique in determining metastases to the axilla. PET/CT has a high sensitivity and specificity regarding the detection of loco‐regional recurrence and metastases to mediastinal and internal mammary lymph nodes, as well as distant metastases. Whether the method can replace conventional methods, or be a supplement when this is non‐conclusive, remains unresolved. PET/CT cannot be recommended for routine follow‐up but is recommended in patients with suspected relapse when conventional imaging has given equivocal results. PET/CT can be applied to confirm isolated loco‐regional relapse or metastatic lesion detected by conventional imaging. PET/CT has a high sensitivity for detecting response to treatment, but a low specificity calls for cautions. Further investigations into the use of PET/CT to predict and monitor response are warranted, before this approach may find its way into a clinical setting. In the future, PET/CT will probably find increasing use in treatment planning and evaluation of patients with breast cancer.     

Water Enema Transvaginal Ultrasound for Local Staging of Stenotic Rectal Carcinoma

Background: To increase the value of ultrasound in the staging of stenotic rectal carcinoma. Methods: Water enema transvaginal ultrasound (WE-TVUS) was performed in 21 consecutive female patients with severely stenotic rectal tumor (adenocarcinoma histologically proved) who were selected on the basis of clinical and double-contrast barium enema study. All patients underwent surgery, and histopathologic correlation was possible. Results: Rectal tumors were well demonstrated in all cases, and a good correlation between perirectal neoplastic infiltration, and lymph node involvement at WE-TVUS and histologic data were observed. Compared with histologic results, WE-TVUS correctly staged 19 of 21 tumors (overall accuracy = 90%); one case was understaged (T4 as T3) and one case was overstaged (T3 as T4). In the detection of lymph node involvement, the sensitivity was 50% and specificity was 78%. Conclusion: WE-TVUS is a potentially valuable technique for defining the local extension of severely stenotic rectal tumors in women. Received: 10 December 1997/Accepted: 28 January 1998     

2-deoxy-2-[F-18]fluoro-D-glucose imaging with positron emission tomography for initial staging of Hodgkin's disease and lymphoma.

PURPOSE: To assess the accuracy of 2-Deoxy-2-[F-18] Fluoro-D-Glucose positron emission imaging (FDG-PET) for staging Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) compared to conventional staging (CS) and to evaluate the impact on patient management. METHODS: Forty-five consecutive patients with lymphoma underwent whole-body FDG-PET imaging for initial staging. Discordant lesions were verified with biopsy or clinical follow-up. The impact on staging and management was reviewed retrospectively. RESULTS: A total of 129 sites of disease were identified, and 88 of those were concordant. FDG-PET and conventional staging demonstrated 24 and 17 additional sites, respectively. FDG-PET correctly upstaged five patients and down-staged two patients (16% total), leading to a change in therapy in 6/45 (13%) patients. However, FDG-PET understaged three patients (7%), correctly staged by conventional staging modalities. Assuming that the addition of FDG-PET to conventional staging modalities is 100% accurate for staging lymphoma, the accuracy of FDG-PET alone was 91%, compared to 84% for conventional staging modalities. CONCLUSIONS: FDG-PET is a noninvasive and efficient imaging modality for staging patients with lymphoma and should be used in conjunction with conventional staging modalities, as they appear complementary.     

Merkel Cell Carcinoma: Is there a Role for 2-Deoxy-2-[F-18]fluoro-d-glucose-Positron Emission Tomography/Computed Tomography?

Purpose 2-Deoxy-2-[F-18]fluoro-d-glucose (FDG)–positron emission tomography (PET)/computed tomography (CT) is becoming widely available as a powerful imaging modality, combining the ability to detect active metabolic processes and their morphologic features in a single study. The role of FDG-PET/CT is proven in lymphoma, melanoma, colorectal carcinoma, and other cancers. However, there are rare malignancies such as Merkel cell carcinoma that can potentially be evaluated with PET/CT. We were therefore prompted to review our experience with FDG-PET/CT in the management of patients with Merkel cell carcinoma.Procedures This is a retrospective case series of six patients with Merkel cell carcinoma, 58–81 years old (average 69 ± 8.3), who had whole-body PET/CT at our institution from January 1st, 2003 to August 31st, 2005. Two patients were women and four were men. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed.Results Twelve examinations were acquired for the six patients (one patient had six PET/CT, one patient had two PET/CT, and four patients had one PET/CT). The injected FDG doses ranged 381.1–669.7 MBq (average 573.5 ± 70.3). Four patients had the PET/CT as part of initial staging, and two patients had the exam for restaging (after surgery and XRT). A total of six Merkel lesions (pancreas, adrenal, lip, submandibular lymph nodes, cervical lymph nodes, and parapharyngeal soft tissue) were identified in three patients and confirmed on histopathological examination. The FDG uptake in these areas was intense, with maximum standardized uptake value (SUVmax) values of 5–14 (average 10.4 ± 3.8). In one patient, the PET/CT scan identified abnormal focal distal sigmoid uptake that was biopsied and diagnosed as adenocarcinoma. Two patients had negative scans and had no clinical evidence of disease on follow-up office visits (up to one year after PET/CT).Conclusions This case series suggests that FDG-PET/CT may have a promising role in the management of patients with Merkel cell carcinoma.     

Rectal carcinoma: Preoperative staging and detection of postoperative local recurrence with transrectal and transvaginal ultrasound

Transrectal ultrasound (TRUS) was performed preoperatively in 35 patients with rectal carcinoma and the results were compared to histologic findings. In the same group, postoperative studies were performed in 22 patients; in women, transvaginal ultrasound (TVUS) was added to the transrectal study. According to Duke's classification modified by Astler-Coller, in relation to the T parameter, TRUS correctly staged 33 of 35 neoplasms (accuracy, 94.3%); one was overstaged and one was understaged. In detection of lymph node involvement, accuracy was 74% (sensitivity 69%, specificity 73.9%). Recurrent local tumors, histologically confirmed, developed in two of 22 postoperative patients who had undergone curative anterior resection. This study demonstrates that TRUS is an accurate method in preoperative staging of rectal carcinoma. In the prospective study, the role of follow-up TRUS and TVUS in detection of local recurrences is evaluated.     

Mediastinal staging of non-small cell lung carcinoma using computed and positron-emission tomography

BACKGROUND: We evaluated the accuracy of computed tomography (CT) and positron-emission tomography (PET) in the mediastinal staging of non-small cell lung cancer. METHODS: Between May 14, 1999, and November 28, 2000, computerized tomography (CT) and positron-emission tomography (PET) were used to clinically stage 94 consecutive patients with non-small cell carcinoma of the lung (NSCCL). All patients underwent subsequent surgical staging with mediastinoscopy, anterior mediastinotomy, and/or thoracotomy with mediastinal lymphadenectomy. RESULTS: Overall accuracy was the same for both procedures. False-negative results occurred 3 times more often with CT; false-positive results occurred twice as often with PET. Sensitivity and specificity were 64% and 94%, respectively, for CT, versus 88% and 86%, respectively, for PET. Positive and negative predictive values were 80% and 88%, respectively, for CT, versus 71% and 95%, respectively, for PET. CONCLUSION: In addition to routine use of CT, PET seems to achieve high negative predictive value in the evaluation of mediastinal disease; PET seems particularly helpful in assessing absence of tumor in bulky nodes after neoadjuvant chemotherapy and/or radiotherapy.     

Comparison of bone and 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography in the evaluation of bony metastases in lung cancer.

Positron emission tomography (PET) is a proven accurate modality used for the detection of active malignant tumors. The performance of PET in detecting bony metastases, however, has not been adequately investigated. PURPOSE: The aim of this study was to compare the performance of bone and 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET scans in evaluating bony metastases from lung cancer. PROCEDURE: This retrospective study evaluated 85 patients with lung cancer who underwent both FDG-PET and bone scans within three weeks of each other for initial staging or restaging. The number and sites of bony lesions on FDG-PET and bone scans were correlated. Concordant lesions between the two modalities were considered to be positive for malignancy; discordant lesions were compared with X-rays, computed tomography (CT), magnetic resonance imaging (MRI), and/or follow-up findings. The mean follow-up interval was 7.9 months. RESULTS: Bone scans were positive for lesions in 24 patients and negative in 61 patients while FDG-PET was positive for bony lesions in 17 patients and negative in 65 patients. FDG-PET was indeterminate for rib involvement in three patients having an underlying lung cancer, whom were evaluated separately. A total of 88 and 41 bony lesions were identified on bone scans and FDG-PET, respectively. Correlation of bone scans with other imaging modalities and clinical follow-up findings revealed a sensitivity, specificity, positive and negative predictive value of 81%, 78%, 34%, and 93%, respectively and for FDG-PET 73% (P=0.81), 88% (P=0.03), 46% (P=0.5,) and 97% (P=0.04), respectively. Using bone scans, 10 patients were correctly diagnosed with bony metastases, 54 were correctly diagnosed free of bony metastases, 17 patients were falsely diagnosed with metastases, and metastases were missed in one patient. Using FDG-PET scans, eight patients were correctly diagnosed with bony metastases, 66 were correctly diagnosed free of bony metastases, seven patients were falsely diagnosed with metastases, and one patient had metastases which were missed. Of the three patients with lung cancer close to the chest wall in whom FDG-PET was indeterminate for rib involvement, the bone scans were truly positive for rib involvement in two of them, and truly negative in the remaining patient. CONCLUSIONS: FDG-PET scans demonstrated significantly higher specificity and negative predictive values than bone scans for evaluating bony metastases from lung cancer. On the other hand, bone scans are more sensitive with higher positive predictive values than FDG-PET scans, but the differences were not statistically significant.     

2-Deoxy-2-[F-18]Fluoro-d-Glucose–Positron Emission Tomography/Computed Tomography Imaging Evaluation of Esophageal Cancer

We evaluated the clinical utility of 2-deoxy-2-[F-18]fluoro-d-glucose (FDG)–positron emission tomography (PET)/computed tomography (CT) on the precise localization of pathologic foci and exclusion of normal variants in the imaging evaluation of patients with esophageal carcinoma. Combined PET/CT scans were performed in 60 patients (50 males, 10 females, age range 47–84 years) with history of esophageal carcinoma either at the time of initial diagnosis (group I, n = 14) or for surveillance and/or detection of recurrent and metastatic disease (group II, n = 46). Prior treatments included esophagectomy with gastric pull-up (n = 23), surgery and chemotherapy (n = 3), surgery and chemoradiation therapy (n = 10), chemotherapy alone (n = 5), radiation therapy alone (n = 2), and chemoradiation without surgery (n = 3). Diagnostic validation was by tissue sampling in three patients and clinical/radiological follow-up for up to 1.5 years in the remaining patients. In group I, discordant abnormalities were noted in seven patients. PET demonstrated hypermetabolism in normal-size lymph nodes on CT in three patients that were considered likely true positive in view of concurrent existence of other adjacent enlarged hypermetabolic lymph nodes in the same nodal basin. Hypometabolic incidental CT abnormalities of up to 1-cm lung nodules were noted in three patients and pleural effusion in one patient, which were considered true negative in view of no change on follow-up PET/CT studies. In group II, both PET and CT showed concordant abnormalities in 23 patients. The precise image fusion of hypermetabolism in a liver lesion allowed a diagnostic CT-guided biopsy in one patient. PET demonstrated true positive hypermetabolic abnormalities in four patients that localized to structures, which were normal by noncontrast CT criteria, and true negative in one patient with hepatic fatty deposits. PET showed decline in metabolic activity of the primary lesion in one patient after chemotherapy, while the corresponding CT abnormality remained unchanged. PET/CT image fusion provided relevant complementary diagnostic information in 14 patients with discordant findings (23% of total) that resulted in biopsy in three cases, institution of chemotherapy in four cases, and a wait-and-watch strategy in seven cases. In conclusion, our findings add to the current body of literature that suggests that FDG-PET/CT scanning may improve the imaging evaluation of patients with esophageal cancer by providing complementary structural-metabolic information. In particular, our findings support the notion that PET/CT may be the most appropriate imaging modality in the evaluation of patients of esophageal cancer that may impact patient management.     

18F-FDG PET/CT在结直肠癌术后血清癌胚抗原阳性患者中的临床应用

目的探讨¹⁸F-FDG PET/CT检测结直肠癌术后血清癌胚抗原（CEA）阳性患者中复发和转移灶的价值。 方法回顾性分析60例结直肠癌术后CEA阳性且接受PET/CT检查的患者,将PET/CT检出结果与病理及随访结果进行比较。 结果¹⁸F-FDG PET/CT诊断阳性50例,假阳性1例;阴性10例,假阴性3例。PET/CT诊断结直肠癌术后CEA阳性患者复发和转移灶的灵敏度为94.2%（49/52）,特异度为87.5%（7/8）,阳性预测值为98.0%（49/50）,阴性预测值为70.0%（7/10）,准确率为93.3%（56/60）。 结论¹⁸F-FDG PET/CT在结直肠癌术后血清CEA阳性患者中有较高的临床应用价值,其对复发及转移灶的检测具有较高的灵敏度、特异度及准确率。     

Detection of Occult Medullary Thyroid Cancer Recurrence with 2-Deoxy-2-[F-18]fluoro-<Emphasis Type="SmallCaps">d</Emphasis>-glucose-PET and PET/CT

Purpose 2-Deoxy-2-[F-18]fluoro-d-glucose (FDG)-positron emission tomography (PET) has an established role in restaging of various cancers, including papillary and undifferentiated thyroid carcinoma. However, controversies exist regarding its ability to reliably assess recurrent medullary thyroid cancer (MTC). We were therefore prompted to review our experience with FDG-PET for detection of occult MTC. Methods This is a retrospective study (Apr 1, 1997–Mar 31, 2004) of 13 patients with histologic diagnosis of MTC, who had PET examinations. The group included six men and seven women, 15–62 years old (average: 48 ± 13). The PET scan request was triggered by rising levels of calcitonin and negative anatomical imaging studies. Results Recurrent/metastatic disease was identified by PET in seven (54%) of the 13 patients. The lesions were located in superior mediastinum (4), cervical lymph nodes (3), thyroid bed (2), lung (1) and liver (1). The calcitonin levels ranged from 52 to 5,090 pg/ml (average: 1,996 pg/ml) in patients with negative PET scans and from 132 to 9,500 pg/ml (average: 3,757 pg/ml) in patients with positive studies. The sensitivity and specificity of FDG-PET for disease detection in this cohort were 85.7% (95% CI: 48.7–97.4) and 83.3 % (95 % CI: 43.6–96.9), respectively. Conclusion Our findings suggest a significant role for FDG-PET in patients with suspected MTC recurrence, with sensitivity of 85.7% and specificity of 83.3% for disease detection. FDG-PET provides additional information in a significant fraction of cases (54%) and could be used for restaging of patients with MTC and elevated levels of biomarkers (calcitonin). Additional studies are necessary to further evaluate the role of FDG-PET in MTC.     

Additional Value of FDG-PET/CT in Management of “Solitary” Liver Metastases: Preliminary Results of a Prospective Multicenter Study

Background and aim

The most common malignancy affecting the liver is metastasis from a wide variety of tumors, particularly those of gastrointestinal origin. Successful surgical removal of a solitary liver metastasis may significantly extend survival and optimal preoperative assessment in this regard is a mandatory prerequisite for proper patient selection. The addition of positron emission tomography/computed tomography (PET/CT) to other more conventional imaging procedures (e.g., ultrasound (US), CT, and magnetic resonance) has the potential to greatly improve the selection process by the combination of high-resolution anatomy afforded by CT directly combined with the functional scintigraphic map of intra- and extrahepatic lesions depicted by 2-deoxy-2-[F-18]fluoro-d-glucose (FDG)-PET. In this study, we assess the additional value of PET/CT in the management strategy of patients with solitary liver metastasis from colorectal and other cancers identified by conventional imaging methods.

Methods

We evaluated 43 consecutive patients (17 males, 26 females, mean age 53?±?6 years) with known solitary liver metastasis. This sample consisted of 18 patients with colorectal cancer, 15 with nonsmall cell lung cancer, six with breast carcinoma, and four ovarian cancers. In addition to contrast-enhanced CT and US, all patients were studied with FDG-PET/CT before surgery. PET/CT was performed within 3 weeks of the initial diagnosis and the scans were read by two experienced radiologists/nuclear medicine specialists blinded to the clinical data. A final diagnosis was obtained at surgery in 31 patients, by fine needle biopsy in five, and long-term clinical, biochemical, and follow-up imaging in seven patients.

Results

In 12 out of 43 patients (28%), PET/CT resulted in restaging disease and a change in therapy. Twenty-two of 31 patients with confirmed solitary liver lesions (71%) were disease-free, eight of 31 (26%) developed a new recurrence, and one of 31 (3%) died from disease progression over a 17?±?6-month follow-up interval. Nine of 12 patients (75%) with multiple metastases demonstrated by FDG-PET/CT were alive with disease and three of 12 (25%) deceased due to disease progression (p?<?0.01) over a 17?±?6-month follow-up interval.

Conclusion

The addition of FDG-PET/CT to the routine assessment of patients with liver metastasis has a significant impact on disease staging and selection of suitable candidates for solitary liver metastasis resection and outcome.