Clinical Usefulness of 18F-fluoride Bone PET

Purpose

¹⁸F-fluoride bone positron emission tomography (PET) has been reported as a useful bone imaging modality. However, no clinical bone PET study had been performed previously in Korea. The authors investigated the usefulness of ¹⁸F-fluoride bone PET in Korean patients with malignant or benign bone disease.

Methods

Eighteen consecutive patients (eight women, ten men; mean age, 55 ± 12 years) who had undergone ¹⁸F-fluoride bone PET for the evaluation of bone metastasis (n = 13) or benign bone lesions (n = 5) were included. The interpretation of bone lesions on ¹⁸F-fluoride bone PET was determined by consensus of two nuclear medicine physicians, and final results were confirmed using combination of all imaging studies and/or clinical follow-up. The analysis was performed on the basis of lesion group.

Results

Thirteen patients with malignant disease had 15 lesion groups, among which seven were confirmed as metastatic bone lesions and eight were confirmed as non-metastatic lesions. ¹⁸F-fluoride bone PET correctly identified six of seven metastatic lesions (sensitivity, 86%), and seven of eight non-metastatic lesions (specificity, 88%). On the other hand, five patients with benign conditions had five bone lesion groups; four were confirmed as benign bone diseases and the other one was confirmed as not a bone lesion. ¹⁸F-fluoride bone PET showed correct results in all the five lesion groups.

Conclusions

¹⁸F-fluoride bone PET showed promising potential for bone imaging in Korean patients with malignant diseases as well as with various benign bone conditions. Therefore, further studies are required on the diagnostic performance and cost-effectiveness of ¹⁸F-fluoride bone PET.     

Impact of Nonosseous Findings on 18F-NaF PET/CT in a Patient with Ductal Breast Carcinoma

¹⁸F-NaF was used as a bone-seeking PET tracer for skeletal imaging until the introduction of the widely available ^99mTc-labeled bone agents. However, there is renewed clinical interest in ¹⁸F-NaF since prior technical and logistic limitations to its routine use are no longer present, and, as a consequence, it is likely that uptake unrelated to bone and non-osseous findings will be encountered more frequently. As a result of tumoral necrosis, soft tissue metastases may demonstrate ¹⁸F-NaF avidity due to dystrophic calcification. On the other hand, all non-osseous findings, whether ¹⁸F-NaF avid or not, may provide important diagnostic information that may alter the course of the disease, including treatment options. Herein we present a patient with ductal carcinoma of the breast in whom findings unrelated to the skeletal system in ¹⁸F-NaF PET/CT altered the treatment strategy.     

Comparison of 18F-NaF PET/CT with Other Imaging Methods in the Detection of Bone Metastases in Patients with Medullary Thyroid Cancer: a Report of a Series of 31 Cases

PurposeTo compare the ¹⁸F-NaF PET/CT studies (¹⁸F-NaF) with other imaging methods in the detection of skeletal metastases (SM) in patients with medullary thyroid cancer (MTC).MethodsWe retrospectively analyzed 31 patients with MTC who performed ¹⁸F-NaF to assess SM. The results of the ¹⁸F-NaF were compared with other imaging methods performed for metastasis detection: ⁹⁹Tc-MDP bone scan (BS), magnetic resonance imaging (MRI), contrast-enhanced CT (CT), and ⁶⁸Ga-Dotatate and ¹⁸F-FDG PET/CT studies. A qualitative analysis comparing the ¹⁸F-NaF findings with the ones of the other methods was performed, and the results were classified as superior (>), equal (=), and inferior (<).ResultsEleven patients had no bone metastases detected on any of the imaging methods used. Twenty patients presented SM depicted on ¹⁸F-NaF. Of these 20 patients, 12 performed bone scan (in 9 ¹⁸F-NaF > BS and in 3 ¹⁸F-NaF = BS), 1 performed ¹⁸F-FDG (¹⁸F-NaF > ¹⁸F-FDG), 4 performed ⁶⁸Ga-Dotatate (in 2 ¹⁸F-NaF > ⁶⁸Ga-Dotatate and in 2 ¹⁸F-NaF = ⁶⁸Ga-Dotatate), 20 performed CT of at least one body segment (in 15 ¹⁸F-NaF = CT and in 5 ¹⁸F-NaF > CT), and 16 performed MRI of at least one body segment, and in all of them, the ¹⁸F-NaF was equal to the MRI. Beside this, the ¹⁸F-NaF detected SM in body segments not routinely scanned in MRI and CT.ConclusionIn patients with MTC, the ¹⁸F-NaF seems to be equal or superior to other imaging modalities in the detection of SM and allows the analysis of the whole skeletal in a single study.     

The Prognostic Value of 18F-FDG PET/CT for Early Recurrence in Operable Breast Cancer: Comparison with TNM Stage

Purpose

We evaluated whether the maximum standardized uptake values (SUV_max) of primary tumor from the initial staging by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) of patients with breast cancer could identify patients at risk for early recurrence within 2 years, particularly in comparison to the American Joint Committee on Cancer (AJCC) stage.

Methods

We reviewed the staging ¹⁸F-FDG PET/CT images of patients with primary breast cancer and their medical records. The SUV_max of the primary tumor was measured. The presence or absence of FDG uptake in the axillary lymph node (ALN) was also assessed. The patient’s pathologic primary tumor stage (pT), pathologic regional lymph node stage (pN), stage grouping, age, estrogen receptor (ER) and progesterone receptor (PR) status, and neoadjuvant chemotherapy history were evaluated with the FDG uptake parameters for recurrence within 2 years following the end of first-line therapy.

Results

Recurrence within 2 years was present in 9.1 % (n = 40) out of the 441 patients assessed. The FDG uptake in ALN, pT, pN, stage grouping and neoadjuvant chemotherapy history were prognostic for early recurrence, while primary tumor SUV_max, age, and ER or PR status were not significant on logistic regression. On multivariate analysis, only the stage grouping (odds ratio 2.79; 95 % CI 1.73, 4.48; p < 0.0001) and neoadjuvant chemotherapy history (odds ratio 2.70; 95 % CI 1.22, 5.98; p = 0.0141) could identify patients at increased risk for recurrence within 2 years.

Conclusions

Primary tumor FDG uptake measured by SUV_max, and visual assessment of FDG uptake in the ALN in the initial staging PET/CT of patients with breast cancer may not have additional prognostic value compared with the AJCC stage grouping for early recurrence.     

Breast Sparganosis Incidentally Detected by FDG PET/CT

Sparganosis is a rare, parasitic infection that is caused by the plercercoid tapeworm larvae of the genus Spirometra. Sparganosis is transmitted by ingestion of larvae-containing water or intermediate hosts, such as raw amphibians, and usually presented with a subcutaneous nodule in the abdominal wall, extremities, and genital organs. Among the various involved organs, the breast is a seldom encountered site for sparganosis. However, breast sparganosis has clinical importance, since it is generally presented with an indolent palpable mass that mimics malignancy, even without evidence of inflammation. Herein, we report a case of breast sparganosis that was detected incidentally by FDG PET/CT during staging work ups in a patient with gall bladder cancer.     

Inflammatory Pseudotumor in the Mediastinum: Imaging with 18F-Fluorodeoxyglucose PET/CT

Mediastinal inflammatory pseudotumor is a rare benign disease with its capability for local invasion and rapid growth. We present a case of middle-mediastinal inflammatory pseudotumor and report its contrast-enhanced chest computed tomography, ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography and pathologic findings.     

(18)F-FDG PET versus (18)F-FDG PET/CT for adrenal gland lesion characterization: a comparison of diagnostic efficacy in lung cancer patients.

OBJECTIVE: The aim of this study was to assess the diagnostic efficacy of integrated PET/CT using fluorodeoxyglucose (FDG) for the differentiation of benign and metastatic adrenal gland lesions in patients with lung cancer and to compare the diagnostic efficacy with the use of PET alone. MATERIALS AND METHODS: Sixty-one adrenal lesions (size range, 5-104 mm; mean size, 16 mm) were evaluated retrospectively in 42 lung cancer patients. Both PET images alone and integrated PET/CT images were assessed, respectively, at two-month intervals. PET findings were interpreted as positive if the FDG uptake of adrenal lesions was greater than or equal to that of the liver, and the PET/CT findings were interpreted as positive if an adrenal lesion show attenuation > 10 HU and showed increased FDG uptake. Final diagnoses of adrenal gland lesions were made at clinical follow-up (n = 52) or by a biopsy (n = 9) when available. The diagnostic accuracies of PET and PET/CT for the characterization of adrenal lesions were compared using the McNemar test. RESULTS: Thirty-five (57%) of the 61 adrenal lesions were metastatic and the remaining 26 lesions were benign. For the depiction of adrenal gland metastasis, the sensitivity, specificity, and accuracy of PET were 74%, 73%, and 74%, respectively, whereas those of integrated PET/CT were 80%, 89%, and 84%, respectively (p values; 0.5, 0.125, and 0.031, respectively). CONCLUSION: The use of integrated PET/CT is more accurate than the use of PET alone for differentiating benign and metastatic adrenal gland lesions in lung cancer patients.     

Multifocal Colonic Lesions Detected by 18F-FDG PET/CT: Correlation with Histopathology and Gross Specimen

A 73-year-old man underwent ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) for the staging of colon cancer. The ¹⁸F-FDG PET/CT revealed three colonic lesions. The histopathologic examination of the postoperative gross specimen revealed a tubular adenoma, a tubulovillous adenoma and an adenocarinoma. The maximal standardized uptake value (SUVmax) of a tubulovillous adenoma was much higher than that of adenocarcinoma. This patient could be considered as a representative case highlighting that SUVmax is not a reliable indicator for discriminating colon cancer from colonic adenomas.     

Pulmonary Actinomycosis Imitating Lung Cancer on 18F-FDG PET/CT: A Case Report and Literature Review

Here we report a case of 41-year-old man with a soft tissue density mass at right upper lung and palpable abscesses at right upper backside and right wrist. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography demonstrated a 7.8 × 5.0 cm mass with soft-tissue density in the upper lobe of the right lung with high metabolic activity. The infiltrative mass extended to adjacent chest wall soft tissue. Final diagnosis of pulmonary actinomycosis with multiple abscesses was made. The patient responded well to antibiotics treatment.     

Primary Malignant Fibrous Histiocytoma in Mediastinum: Imaging with 18F-FDG PET/CT

Malignant fibrous histiocytoma (MFH) is the most common soft tissue tumor which often occurs in the extremities and the retroperitoneum. Primary mediastinal MFH is rare; thus, findings on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) of mediastinal MFH have not been reported yet. We report herein the case of a 64-year-old man who was presented with a superior mediastinal mass. The mass showed intense ¹⁸F-FDG uptake with central metabolic defect on PET/CT. The maximum standardized uptake value was 17.4. After tumor removal via median sternotomy, an MFH of the storiform-pleomorphic type was diagnosed on histopathologic examination. We present the first report of ¹⁸F-FDG PET/CT imaging of MFH in the superior mediastinum.     

The Clinical Usefulness of 18F-FDG PET/CT for the Evaluation of Lymph Node Metastasis in Periorbital Malignancies

Objective

The aim of this study was to assess the clinical role of ¹⁸F-FDG PET/CT for the evaluation of lymph node metastasis in periorbital malignancies, compared with CT alone.

Materials and Methods

We analyzed eighteen PET/CT and CT scans in 15 patients with biopsy-proven periorbital malignancies. We compared the diagnostic capabilities of PET/CT and CT with regard to nodal metastasis by level-by-level analysis and by N staging prediction. The reference standards were surgical pathology (n = 7) from dissected lymph node specimens and the results from radiological follow-up (n = 11, mean 20.5 months; range 10-52 months). Moreover, any changes in patient care as prompted by PET/CT were recorded and compared with treatment planning for CT alone.

Results

PET/CT had a sensitivity of 100%, while CT had a sensitivity of 57% (p = 0.03) for nodal metastasis by level-by-level analysis. PET/CT had a specificity of 97%, positive predictive value of 93%, negative predictive value of 100%, and diagnostic accuracy of 98%, while the CT values for these same parameters were 97%, 89%, 82%, and 84%, respectively. PET/CT correctly predicted N staging with an accuracy of 100%, while CT was only 83% accurate (p = 0.01). Regarding the impact on patient care, the extent of surgery for regional lymph nodes and the treatment decision were modified by PET/CT in 39% of patients.

Conclusion

PET/CT could provide useful information in the management of regional lymph node metastases in patients with periorbital malignancies.     

Usefulness of <Superscript>18</Superscript>F-FDG PET/CT to Detect Metastatic Mucinous Adenocarcinoma Within an Inguinal Hernia

Metastatic mucinous adenocarcinoma in an inguinal hernia is a rare disease and the image findings of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) are little known. Here, we introduce a 57-year-old man with metastatic mucinous adenocarcinoma in an inguinal hernia. On initial ¹⁸F-FDG PET/CT, hypermetabolism was observed in mucinous adenocarcinoma of the cecum, and adenocarcinomas of the transverse and ascending colon, respectively. Follow-up ¹⁸F-FDG PET/CT revealed newly developed multiple hypermetabolism in peritoneal seeding masses and nodules in the pelvic cavity and scrotum. Peritoneal carcinomatosis in the right pelvic side wall was extended to the incarcerated peritoneum and mesentery in the right inguinoscrotal hernia.¹⁸F-FDG PET/CT was useful to reveal unexpected peritoneal seeding within the inguinal hernia. Also, this case demonstrated that metastatic mucinous adenocarcinomas had variably intense FDG uptake.     

Retroperitoneal Bronchogenic Cyst Presenting Paraadrenal Tumor Incidentally Detected by 18F-FDG PET/CT

A follow-up ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET/CT scan of a 57-year-old asymptomatic male who had undergone total thyroidectomy for thyroid cancer revealed a 5.0 × 4.0-cm, well-defined, ovoid-shaped mass around the left adrenal gland without definite FDG uptake. On the adrenal CT scan, the left paraadrenal tumor showed high attenuation on the precontrast scan without enhancement. The average Hounsfield unit (HU) was 58.1 on the precontrast scan and 58.4 on the postcontrast scan. The patient underwent laparoscopic adrenalectomy for resection of the left paraadrenal tumor. The final histopathologic examination revealed a bronchogenic cyst. Although retroperitoneal bronchogenic cysts are rare, they should be considered in the differential diagnosis of retroperitoneal cystic tumors. The preoperative diagnosis is difficult, but a contrast-enhanced CT scan or ¹⁸F-FDG PET/CT scan may be useful for differentiating hyperattenuated cysts from other soft tissue masses.     

Direct comparison of [18F]FDG PET/CT with PET alone and with side-by-side PET and CT in patients with malignant melanoma

Purpose

The purpose of this retrospective, blinded study was to evaluate the additional value of [¹⁸F]FDG PET/CT in comparison with PET alone and with side-by-side PET and CT in patients with malignant melanoma (MM).

Methods

A total of 127 consecutive studies of patients with known MM referred for a whole-body PET/CT examination were included in this study. PET alone, side-by-side PET and CT and integrated PET/CT study were independently and separately interpreted without awareness of the clinical information. One score each was applied for certainty of lesion localisation and for certainty of lesion characterisation. Verification of the findings was subsequently performed using all available clinical, pathological (n?=?30) and follow-up information.

Results

The number of lesions with an uncertain localisation was significantly (p?p?p?=?0.057) compared versus PET alone. Respectively, PET, side-by-side PET and CT and PET/CT showed a sensitivity of 86%, 89% and 91%, a specificity of 94%, 94% and 94%, a positive predictive value of 96%, 96% and 96% and a negative predictive value of 80%, 83% and 87%.

Conclusion

Integrated PET/CT offers a significant benefit in lesion localisation and an improvement in lesion characterisation compared with PET alone or with side-by-side PET and CT. The benefit is not as great as that reported for other tumour entities, which may be due to the high avidity of MM for [¹⁸F]FDG.     

Nonfunctioning endocrine pancreatic tumor examined with 18F-FDG PET/CT

A 71-year-old woman with type 2 diabetes mellitus complained of generalized fatigue. A 36-mm tumor in the pancreatic tail was detected with ultrasonography. The tumor was found to have marked hypervascularity with contrast-enhanced computed tomography (CT) and magnetic resonance. Combined ¹⁸F-fluorodeoxyglucose positron emission tomography and CT (¹⁸F-FDG PET/CT) showed ¹⁸F-FDG by the tumor with a maximal standardized uptake value of 2.98 at 50 min and 3.29 at 100 min following injection of ¹⁸F-FDG. ¹⁸F-FDG PET/CT suggested no extrapancreatic spread of the tumor. The patient had no pancreatic hormone-associated symptoms. Distal pancreatectomy was performed, and a well-differentiated endocrine tumor was diagnosed. The resected specimen showed neither infiltration of adjacent structures nor metastasis to regional lymph nodes. The present case suggests that ¹⁸F-FDG PET/CT is a reliable modality for staging endocrine pancreatic tumors.     

Hypermetabolic Axillary Mass on 18F FDG PET/CT: Breast Cancer Arising from Accessory Breast Tissue

Differential diagnosis among several causes of axillary malignant mass is important. The most common cause of palpable malignant axillary mass is metastatic lymphadenopathy. Although carcinoma arising from ectopic breast tissue is rare, the diagnosis should be kept in mind when evaluating malignant axillary mass. In this report we present a case with carcinoma arising from ectopic breast tissue. ¹⁸F FDG PET/CT was performed for the purpose of localizing primary breast cancer lesion and systemic evaluation. PET/CT showed hypermetabolic lesions only in the right axilla. There is no evidence of malignancy in both breasts. When nuclear physicians encounter a hypermetabolic axillary mass indicating malignant lesion without evidence of primary breast malignant lesion, carcinoma arising from ectopic breast tissue should be included in the differential diagnosis.     

Breast MRI and<Superscript>18</Superscript>F FDG PET/CT in the management of breast cancer

GOALS: 18F FDG PET/CT is used for diagnosis, staging and establishing the response to therapy in various malignancies, including breast cancer (BC). Dedicated breast MRI (BMRI) is gaining a role in the management of BC patients (pts), demonstrating high sensitivity and specificity for detection of small lesions. We were therefore prompted to review our experience with PET and BMRI in BC. METHODS: This is a retrospective study of 21 women with BC, 30-76 years old, who had BMRI and whole-body FDG PET/CT at our institution from Jun 2002 to May 2005. A total of 6 patients (group A) had BMRI and PET/CT in the preoperative period and 15 patients (group B) had BMRI and PET/CT after surgery. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed. RESULTS: For group A, BMRI identified breast lesions in 4 patients, while PET/CT was able to identify breast lesions in 5 patients. All these were proven to be malignancy on pathology examination. In group B, BMRI detected recurrent breast lesions in 8 patients, with 88.9% sensitivity and 83.3% specificity. In the same patient population, PET/CT was 33.3% sensitive and 91.7% specific. As a whole body examination, PET/CT revealed metastatic disease in 6 patients (100% sensitive and 90% specific). Overall, sensitivities and specificities for breast disease detection were 85.7% and 85.7% for BMRI, and 75% and 92.3% for 18F FDG PET/ CT. CONCLUSIONS: As expected, BMRI is more sensitive than PET/CT in the detection of breast lesions. However, PET/CT as a whole-body examination changed the management of disease by detection of distant lesions in 6 of the 21 patients. Our study suggests that 18F FDG PET/CT and BMRI should be considered as complimentary imaging tools in the pre- and postoperative work-up of patients diagnosed with breast cancer.     

Prognostic Value of Primary Tumor Uptake on F-18 FDG PET/CT in Patients with Invasive Ductal Breast Cancer

Purpose

To determine the prognostic implications of pretreatment F-18 FDG PET/CT in patients with invasive ductal breast cancer (IDC), we evaluated the relationship between FDG uptake of the primary tumor and known prognostic parameters of breast cancer. Prognostic significance of tumoral FDG uptake for the prediction of progression-free survival (PFS) was also assessed.

Materials and Methods

Fifty-five female patients with IDC who underwent pretreatment F-18 FDG PET/CT were enrolled. The maximum standardized uptake value of the primary tumor (pSUVmax) was compared with clinicopathological parameters including tumor size, grade, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor2 (HER2), axillary lymph node (LN) metastasis, and stage. The prognostic value of pSUVmax for PFS was assessed using the Kaplan-Meier method.

Results

A high pSUVmax was significantly related to a higher stage of tumor size (P < 0.05), grade (P < 0.001), and stage (P < 0.001). pSUVmax was significantly higher in ER-negative tumors (P < 0.001), PR-negative tumors (P < 0.001), and positive LN metastasis (P < 0.01), but not different according to HER2 status. pSUVmax was significantly higher in patients with progression compared to patients who were disease-free (10.6 ± 5.1 vs. 4.7 ± 3.5, P < 0.001). A receiver-operating characteristic curve demonstrated a pSUVmax of 6.6 to be the optimal cutoff for predicting PFS (sensitivity; 86.7%, specificity; 82.5%). The patients with a high pSUVmax (more than 6.6) had significantly shorter PFS compared to patients with a low pSUVmax (P < 0.0001).

Conclusions

pSUVmax on pretreatment F-18 FDG PET/CT could be used as a good surrogate marker for the prediction of progression in patients with IDC.     

PET/CT在乳腺癌中的应用

乳腺癌是女性最常见的恶性肿瘤,如能得到早期诊断并早期治疗可明显地改善患者的预后情况甚至可以完全治愈。近年来正电子发射断层显像(PET)以及18F-FDG的广泛应用极大地改善了肿瘤患者的诊断和分期问题,及时改变了相应的治疗方法,而单纯的PET显像由于解剖定位欠清,有时正常生理性摄取与异常病理性摄取可能会难以鉴别,PET/CT的出现弥补了上述缺点,使FDGPET/CT在乳腺癌的分期与再分期、疗效监测、术前评估、原发病灶的诊断以及治疗方案的制订中都体现出自身独特的优势。     

Relations Between Pathological Markers and Radioiodine Scan and 18F-FDG PET/CT Findings in Papillary Thyroid Cancer Patients With Recurrent Cervical Nodal Metastases

Purpose

The aim of this study was to investigate relationships between the immunohistochemical results and radioiodine scan and ¹⁸F-FDG PET findings in papillary thyroid cancer (PTC) patients with recurrent cervical nodal metastases.

Methods

A total of 46 PTC patients who had undergone a radioiodine scan and/or ¹⁸F-FDG PET/CT and a subsequent operation on recurrent cervical lymph nodes were enrolled. Twenty-seven patients underwent ¹⁸F-FDG PET/CT, 8 underwent radioiodine scans, and 11 underwent both scans. In all surgical specimens, the immunoexpressions of thyroglobulin (Tg), sodium-iodide symporter (NIS), glucose transporter 1 (Glut-1), and somatostatin receptor 1 and 2A (SSTR1 and SSTR2A) were assessed, and associations between these expressions and radioiodine scan and ¹⁸F-FDG PET findings were evaluated.

Results

Of the 38 patients who underwent ¹⁸F-FDG PET/CT, all patients with weak Tg expression had positive ¹⁸F-FDG uptake, while only 45 % of the patients with moderate or strong Tg expression showed positive uptake (p = 0.01). The proportion of patients with positive ¹⁸F-FDG uptake increased as the degree of Glut-1 expression with luminal accentuation increased. Of the 19 patients who underwent a radioiodine scan, the proportion with positive radioiodine uptake was greater among patients with strong NIS and SSTR2A expression than among patients expressing these markers at weak levels (p = 0.04 for all). All three patients with weak Tg expression were negative for radioiodine uptake.

Conclusion

The ¹⁸F-FDG uptakes of recurrent cervical nodes are related to strong Glut-1 expression with luminal accentuation and weak Tg expression, whereas radioiodine uptake is related to the strong expressions of NIS and SSTR2A.