Effectiveness of 11C-choline PET/CT in prostate cancer surveillance.

AIM: Our aim was to analyse the performance of [11C]choline PET/CT in prostate cancer (PCa) surveillance, especially in patients with prostate specific antigen (PSA) < 1 ng/mL. MATERIAL AND METHODS: Three hundred and twenty-nine [11C]choline PET/CT examinations from 191 patients (68.2 ±â€¯7.2 years) submitted for PCa surveillance or biochemical recurrence were retrospectively evaluated. PSA at study was 13.0 ±â€¯84.2 ng/mL. Main initial treatment was radical prostatectomy (RP) in 81 patients, and other treatments (radiotherapy, chemotherapy, hormonotherapy) in 110. PET/CT was acquired 20' after injection of 555-740 MBq of [11C]choline. Minimum follow-up was 12 months. RESULTS: Two hundred and nineteen (66.6%) out of the 329 PET/CT examinations were positive. The percentage of positive examinations was significantly higher in patients with other initial treatment than RP compared to patients with RP (85.6% vs. 43.6%, respectively). One hundred and thirty PET/CT (59.4%) showed local recurrence, 48 (21.9%) distant recurrence, and 41 (18.7%) local plus distant recurrence. Initial therapeutic approach was changed in 139 cases (63.5%). In the subgroup of 81 [11C]choline PET/CT scans performed with PSA < 1 ng/mL, 23 (28.4%) showed a positive result. Initial therapeutic approach was changed in 9 (11.1%). Three (4.8%) out of 63 patients died as per PCa. CONCLUSION: [11C]choline PET/CT demonstrated its effectiveness in PCa surveillance and restaging, even in patients with serum PSA < 1 ng/mL. The diagnostic performance was different depending on the initial treatment, been higher in patients with non-surgical treatment.

Contribution of 11C-Choline PET/CT in prostate carcinoma biochemical relapse with serum PSA level below 1 ng/ml. / Aportación de la PET/TC con 11C-colina en la recidiva bioquímica del cáncer de próstata con antígeno específico prostático sérico inferior a 1 ng/ml.

OBJECTIVE: 11C-choline PET/CT has demonstrated good results in the restaging of prostate cancer (PCa) with high serum prostate specific antigen (PSA), but its use in patients with low serum PSA is controversial. Our aim was to evaluate the contribution of 11C-choline PET/CT in patients with PCa, biochemical relapse and PSA <1 ng/ml. MATERIAL AND METHOD: Fifty consecutive patients (mean age: 65.9±5.6 years) with biochemical relapse of PCa and serum PSA <1ng/ml were evaluated retrospectively. PET/CT was performed 20min after intravenous administration of 555-740 MBq of 11C-choline. Minimum follow up time was 30 months. RESULTS: Twenty-one out of 50 patients (42%) had an abnormal 11C-choline PET/CT. In 7 out of 21 patients (14%) tumor was confirmed (4 in prostatic bed, 4 in pelvic lymph nodes, 2 in mediastinal lymph nodes and one synchronous sigmoid carcinoma), and in all cases the initial therapeutic planning was modified. In 2 patients (4%) subsequent tests diagnosed a benign disease (one sarcoidosis, one tuberculosis sequelae) and in 3 patients (6%) they ruled out pathology. The other 9 patients (18%) had no further assessment (7 mediastinal and 4 pelvic lymph nodes). Twenty-nine out of 50 patients (58%) had a normal PET/CT. At 30 months, follow up recurrence was confirmed only in 2 of these patients. CONCLUSIONS: 11C-choline PET/CT proved its usefulness in demonstrating tumor in 14% of patients with BR of PCa and serum PSA <1ng/ml, with therapeutic implications. In 4% of patients a benign condition was detected. A normal 11C-choline PET/CT was associated with a very low rate of recurrence at 30 months.

Candida Esophagitis Incidentally Detected by 18F-FDG PET/CT in Metastatic Lung Adenocarcinoma.

The diagnostic significance of esophageal 18F-FDG uptake in oncologic patient is challenging. It may represent normal physiological uptake, inflammation, infection, or neoplasia. We present a patient with a recent diagnosis of non-small cell lung cancer stage IV and esophageal mild uptake on 18F-FDG PET/CT scan. Biopsy of esophageal mucosa demonstrated Candida esophagitis.

The Role of PET/CT Molecular Imaging in the Diagnosis of Recurrence and Surveillance of Patients Treated for Non-Small Cell Lung Cancer.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer mortality worldwide and its prognosis remains poor. Molecular imaging with 18F-FDG PET/CT can metabolically characterize the nature of lesions as benign or malignant, allowing a better staging at the diagnosis of this kind of patient. This advantage can also be applied in the re-staging due to the suspicion of recurrent disease. Many patients have a recurrence of the disease, including surgically treated patients. In the current context, with new personalized oncological treatments, the surveillance for recurrence and its accurate diagnosis are crucial to improve their survival. In this paper, we revise the current knowledge about the clinical and molecular factors related to the recurrent disease. In the context of new, promising, available personalized treatments, the role of molecular imaging with PET/CT and 18F-FDG and non-18F-FDG radiotracers in the follow-up of NSCLC-treated patients is especially attractive and interesting.

Comparison of 99mTc-sestamibi and 11C-methionine PET/CT in the localization of parathyroid adenomas in primary hyperparathyroidism.

AIM: To evaluate the usefulness of (11)C-methionine PET/CT (MET) in the localization of the parathyroid adenomas and to compare the results with those obtained with the conventional technique in double-phase (99m)Tc-sestamibi scintigraphy (MIBI). We evaluated the optimal timing to acquire MET images. MATERIAL AND METHODS: A prospective study that included 14 patients (mean age: 65.5 ± 9.7 years) with primary hyperparathyroidism (PH) who underwent surgery was performed. Mean serum iPTH was 215.8 ± 108 pg/mL and serum calcium 10.8 ± 0.9 mg/dL. MIBI (planar and SPECT) was obtained 10 min and 2-3h after injection of 740 MBq (20 mCi) of (99m)Tc-sestamibi. MET was obtained 10 min and 40 min after injection of 740 MBq (20 mCi) of (11)C-methionine. MIBI and MET images were visually evaluated and compared. A score for 10 min and 40 min MET images from 0 (no abnormal uptake) to 3 (intense uptake) was assigned. RESULTS: MIBI and MET were positive and concordant in 11/14 patients and in 10 of them the parathyroid adenoma was correctly localized. In 3/14 MIBI was positive and MET negative (MIBI correctly localized the parathyroid adenoma in 2 of them). According to the timing of MET imaging acquisition, the 10 min and 40 min acquisition showed the same score in 10 patients, it was higher at 10 min acquisition in 3 and in 1 the parathyroid adenoma was only detected at 40 min acquisition. CONCLUSION: MIBI remains the technique of choice for the localization of parathyroid adenomas in patients with PH. MET may play a complementary role in selected patients. Delayed acquisition should be included in the MET protocol when the early acquisition is negative.

[Update on the use of PET radiopharmaceuticals in inflammatory disease]. / Actualización del uso de radiotrazadores PET en patología inflamatoria.

The use of molecular imaging with PET/CT technology using different radiotracers, especially the (18)F-FDG is currently spreading beyond the area of oncology, the most interest being placed on inflammatory and infectious diseases. This article presents a review of its contribution in different inflammatory conditions in the context of structural and conventional nuclear medicine imaging. Special emphasis is placed on the more significant diseases such as large-vessel vasculitis, sarcoidosis, rheumatoid arthritis and inflammatory bowel disease and the study of the atheroma plaque.

Evaluation of the contribution of the dynamic phase of lymphoscintigraphy to the detection of sentinel lymph node in breast cancer.

AIM: The aim of this study was to evaluate the contribution of an early dynamic phase (DP) of the lymphoscintigraphy (LS) to the detection of the sentinel lymph node (SLN) in breast cancer. METHODS: This prospective study included 164 breast lesions in 161 consecutive patients (160 women, mean age 57.5 years). Patients with tumor >5 cm, multicentric, palpable nodes, axillary involvement, previous surgery, lymphadenectomy, radio or chemotherapy were not included. All patients underwent preoperative LS before surgery. DP immediately after injection of [99mTc]Nanocolloid followed by early and delayed planar images (EPI and DPI) were acquired. RESULTS: SLN was detected in 162/164 lesions (98.8%). In 115 (71%) DP showed no lymph node uptake and the SLN was identified only by EPI and DPI. A focal uptake by at least one lymph node was observed in DP in the remaining 47 lesions (29%). Although in 30/74 lesions DP did not provide additional information to EPI and DPI, nevertheless in 17 cases (10.5%) DP was essential to identify correctly the SLN. CONCLUSION: We concluded that DP, by allowing a better interpretation of the lymphatic drainage pattern, provides unique information to distinguish the correct SLN from other lymph nodes and is recommended as the first part of LS.

Metabolic response demonstrated by 18F-FDG-PET/CT in metastatic medullary thyroid carcinoma under sorafenib therapy.

A 51-year-old woman with a medullary thyroid carcinoma (MTC) presented with a palpable nodule in the right breast. Serum calcitonin was 1,453 pg/ml and carcinoembryonic antigen was 201 ng/ml. Cervical ultrasound and bone scintigraphy were normal. Computed tomography (CT) showed nodules in the right breast and anterior thoracic wall and a hypodense lesion in the right hepatic lobe. Histology of the breast nodule confirmed metastasis from MTC. To evaluate the metabolic activity of these lesions, 18F-fluorodeoxiglucose positron emission tomography-CT (FDG-PET/CT) scan was requested. Axial fused images revealed high FDG uptake by the breast and thoracic wall nodules and the right hepatic lobe. FDG-PET/CT also showed uptake in sacrum and right iliac bone, undetected by CT and bone scintigraphy. After seven cycles of sorafenib PET/CT became negative. Calcitonin decreased to 82.5. A PET/CT performed 6 months later remained negative. This is the first published image of the complete metabolic response of MTC to sorafenib therapy using FDG-PET/CT.

Evaluation of the contribution of the dynamic phase of lymphoscintigraphy to the detection of sentinel lymph node in breast cancer.

Aim: The aim of this study was to evaluate the contribution of an early dynamic phase (DP) of the lymphoscintigraphy (LS) to the detection of the sentinel lymph node (SLN) in breast cancer. Methods: This prospective study included 164 breast lesions in 161 consecutive patients (160 women, mean age 57.5 years). Patients with tumor >5 cm, multicentric, palpable nodes, axillary involvement, previous surgery, lymphadenectomy, radio or chemotherapy were not included. All patients underwent preoperative LS before surgery. DP immediately after injection of [99mTc]Nanocolloid followed by early and delayed planar images (EPI and DPI) were acquired. Results: SLN was detected in 162/164 lesions (98.8%). In 115 (71%) DP showed no lymph node uptake and the SLN was identified only by EPI and DPI. A focal uptake by at least one lymph node was observed in DP in the remaining 47 lesions (29%). Although in 30/74 lesions DP did not provide additional information to EPI and DPI, nevertheless in 17 cases (10.5%) DP was essential to identify correctly the SLN. Conclusion: We concluded that DP, by allowing a better interpretation of the lymphatic drainage pattern, provides unique information to distinguish the correct SLN from other lymph nodes and is recommended as the first part of LS.

[Evaluation of bone scintigraphy and (18)F-FDG PET/CT in bone metastases of lung cancer patients]. / Evaluación de la gammagrafía ósea y la (18)F-FDG PET/TAC en las metástasis óseas del cáncer de pulmón.

OBJECTIVE: To compare the bone scintigraphy (BS) findings and PET/CT scintigraphy with FDG (FDG PET/CT) in the detection of bone metastases in lung cancer. MATERIAL AND METHODS: We studied 32 patients with lung cancer who underwent FDG PET/CT and BS in a period of 15.9±18.6 days. The results of both techniques were compared with the histology, where available, radiological structural techniques and the clinical follow-up. In 30 patients, a definitive diagnosis was reached with the scintigraphic findings. No final diagnosis was obtained in 2 patients. RESULTS: BS was positive in 25/30 patients (83.3%) and negative in 5 patients. FDG PET/CT was positive in 21/30 patients (70%) and negative in 9. The BS and the FDG PET/CT were positive in 19/30 patients (63.3%) for the detection of bone metastases. In 6/19, both techniques showed the same number of bone lesions. In 10/19, FDG PET/CT showed a greater number of bone metastases than BS. In 3/19 patients, BS showed more lesions than FDG PET/CT and in 2/30 patients (6.6%), the BS was normal and the FDG PET/CT showed bone lesions which were confirmed as metastasis. In 6/30 patients (20%), the FDG PET/CT was negative and the BS was positive. BS and FDG PET/CT scan were normal in 3/30 patients (10%). CONCLUSIONS: In patients with lung cancer, FDG PET/CT scan detected more metastatic bone lesions than BS. It also identified bone metastasis in negative BS. In our experience, when the BS was positive and the FDG PET/CT scan was negative, the lesions observed were mostly related with degenerative bone conditions and bone fractures. In the clinical practice, the FDG PET/CT and BS have a complementary role for the assessment of bone status in lung cancer patients.