In clinically node‐negative patients with early oral cavity cancer, 18Ffludeoxyglucose (FDG) positron emission tomography–computed tomography (PET‐CT) should be compared with sentinel node biopsy. ...Cost effectiveness is one of the important aspects for implementation of FDG/PET‐CT in clinical practice for this patient population.
Objectives
Opportunistic screening for osteoporosis using computed tomography (CT) examinations that happen to visualise the spine can be used to identify patients with osteoporosis. We sought to ...verify the diagnostic performance of vertebral Hounsfield unit (HU) measurements on routine CT examinations for diagnosing osteoporosis in a separate, external population.
Methods
Consecutive patients who underwent a CT examination of the chest or abdomen and had also received a dual-energy X-ray absorptiometry (DXA) test were retrospectively included. CTs were evaluated for vertebral fractures and vertebral attenuation (density) values were measured. Diagnostic performance measures and the area under the receiver operator characteristics curve (AUC) for diagnosing osteoporosis were calculated.
Results
Three hundred and two patients with a mean age of 57.9 years were included, of which 82 (27 %) had osteoporosis according to DXA and 65 (22 %) had vertebral fractures. The diagnostic performance for vertebral HU measurements was modest, with a maximal AUC of 0.74 (0.68 – 0.80). At that optimal threshold the sensitivity was 62 % (51 – 72 %) and the specificity was 79 % (74 – 84 %).
Conclusions
We confirmed that simple trabecular vertebral density measurements on routine CT contain diagnostic information related to bone mineral density as measured by DXA, albeit with substantially lower diagnostic accuracy than previously reported.
Key Points
•
We externally validated the value of vertebral trabecular bone attenuation for osteoporosis
•
These diagnostic performance measures were, however, substantially lower than previously reported
•
This information might be useful when considering the implementation of opportunistic osteoporosis screening
Purpose
To systematically review and meta-analyse published data on the diagnostic performance of
18
F-FDG PET/CT in detecting bone marrow involvement in patients with newly diagnosed diffuse large ...B-cell lymphoma (DLBCL).
Methods
PubMed/MEDLINE and Embase were systematically searched for relevant studies. The methodological quality of each study was assessed. Sensitivities and specificities of FDG PET/CT in individual studies were calculated and meta-analysed with a random effects model. A summary receiver operating characteristic curve (sROC) was constructed with the Moses-Shapiro-Littenberg method. Weighted summary proportions of discrepancies between the FDG PET/CT and (blind) bone marrow biopsy (BMB) results among all patients were calculated.
Results
Seven studies, with a total of 654 patients with newly diagnosed DLBCL, were included. Overall, the quality of the included studies was moderate. The sensitivity and specificity of FDG PET/CT for detecting bone marrow involvement ranged from 70.8 % to 95.8 % and from 99.0 % to 100 %, with pooled estimates of 88.7 % (95 % confidence interval, CI, 82.5 – 93.3 %) and 99.8 % (95 % CI 98.8 – 100 %), respectively. The area under the sROC curve was 0.9983. The weighted summary proportion of FDG PET/CT-negative patients with positive BMB findings among all patients was 3.1 % (95 % CI 1.8 – 5.0 %) and the weighted summary proportion of FDG PET/CT-positive patients with negative BMB findings among all patients was 12.5 % (95 % CI 8.4 – 17.3 %).
Conclusion
FDG PET/CT is accurate and complementary to BMB for detecting bone marrow involvement in patients with newly diagnosed DLBCL. A negative FDG PET/CT scan cannot rule out the presence of bone marrow involvement, but positive FDG PET/CT findings obviate the need for BMB for the detection of bone marrow involvement in these patients.
Purpose
CXCR4 (over)expression is found in multiple human cancer types, while expression is low or absent in healthy tissue. In glioblastoma it is associated with a poor prognosis and more extensive ...infiltrative phenotype. CXCR4 can be targeted by the diagnostic PET agent
68
GaGa-Pentixafor and its therapeutic counterpart
177
LuLu-Pentixather. We aimed to investigate the expression of CXCR4 in glioblastoma tissue to further examine the potential of these PET agents.
Methods
CXCR4 mRNA expression was examined using the R2 genomics platform. Glioblastoma tissue cores were stained for CXCR4. CXCR4 staining in tumor cells was scored. Stained tissue components (cytoplasm and/or nuclei of the tumor cells and blood vessels) were documented. Clinical characteristics and information on IDH and
MGMT
promoter methylation status were collected. Seven pilot patients with recurrent glioblastoma underwent
68
GaGa-Pentixafor PET; residual resected tissue was stained for CXCR4.
Results
Two large mRNA datasets (
N
= 284;
N
= 540) were assesed. Of the 191 glioblastomas, 426 cores were analyzed using immunohistochemistry. Seventy-eight cores (23 tumors) were CXCR4 negative, while 18 cores (5 tumors) had both strong and extensive staining. The remaining 330 cores (163 tumors) showed a large inter- and intra-tumor variation for CXCR4 expression; also seen in the resected tissue of the seven pilot patients—not directly translatable to
68
GaGa-Pentixafor PET results. Both mRNA and immunohistochemical analysis showed CXCR4 negative normal brain tissue and no significant correlation between CXCR4 expression and IDH or
MGMT
status or survival.
Conclusion
Using immunohistochemistry, high CXCR4 expression was found in a subset of glioblastomas as well as a large inter- and intra-tumor variation. Caution should be exercised in directly translating ex vivo CXCR4 expression to PET agent uptake. However, when high CXCR4 expression can be identified with
68
GaGa-Pentixafor, these patients might be good candidates for targeted radionuclide therapy with
177
LuLu-Pentixather in the future.
Objective
Sentinel lymph-node (SLN) mapping for early-stage oral squamous cell carcinoma (OSCC) is comprehensive and consequently time-consuming and costly. This study evaluated the clinical value of ...several SLN imaging components and analyzed the accuracy for SLN identification using a streamlined SLN imaging protocol in early-stage OSCC.
Materials and methods
This retrospective within-patient evaluation study compared both number and localization of identified SLNs between the conventional SLN imaging protocol and a streamlined imaging protocol (dynamic lymphoscintigraphy (LSG) for 10 min directly post-injection and SPECT-CT at ~ 2 h post-injection). LSG and SPECT-CT images of 77 early-stage OSCC patients, scheduled for SLN biopsy, were evaluated by three observers. Identified SLNs using either protocol were related to histopathological assessment of harvested SLNs, complementary neck dissection specimens and follow-up status.
Results
A total of 200 SLNs were identified using the streamlined protocol, and 12 additional SLNs (
n
= 212) were identified with the conventional protocol in 10 patients. Of those, 9/12 were identified on early static LSG and 3/12 on late static LSG. None of the additionally identified SLNs contained metastases; none of those in whom additional SLNs were identified developed regional recurrence during follow-up. Only inferior alveolar process carcinoma showed a higher rate of additionally identified SLNs with the conventional protocol (
p
= 0.006).
Conclusion
Early dynamic LSG can be reduced to 10 min. Late static LSG may be omitted, except in those with a history of oncological neck treatment or with OSCC featuring slow lymphatic drainage. Early static LSG appeared to be contributory in most OSCC subsites.
Purpose
To compare sentinel lymph node (SLN) identification using
68
GaGa-tilmanocept PET/CT lymphoscintigraphy to
99m
TcTc-tilmanocept lymphoscintigraphy (including SPECT/CT) in early-stage oral ...cancer. Furthermore, to assess whether reliable intraoperative SLN localization can be performed with a conventional portable gamma-probe using
99m
TcTc-tilmanocept without the interference of
68
GaGa-tilmanocept in these patients.
Methods
This prospective within-patient comparison pilot study evaluated SLN identification by
68
GaGa-tilmanocept PET/CT lymphoscintigraphy compared to conventional lymphoscintigraphy using
99m
TcTc-tilmanocept (~ 74 MBq) in 10 early-stage oral cancer patients scheduled for SLN biopsy. After conventional
99m
TcTc-tilmanocept lymphoscintigraphy, patients underwent peritumoral administration of
68
GaGa-tilmanocept (~ 10 MBq) followed by PET/CT acquisition initiated 15 min after injection. Intraoperative SLN localization was performed under conventional portable gamma-probe guidance the next day; the location of harvested SLNs was correlated to both lymphoscintigraphic images in each patient.
Results
A total of 24 SLNs were identified by
99m
TcTc-tilmanocept lymphoscintigraphy, all except one were also identified by
68
GaGa-tilmanocept PET/CT lymphoscintigraphy.
68
GaGa-tilmanocept PET/CT lymphoscintigraphy identified 4 additional SLNs near the injection site, of which two harbored metastases. Lymphatic vessels transporting
68
GaGa-tilmanocept were identified by PET/CT lymphoscintigraphy in 80% of patients, while draining lymphatic vessels were visualized by
99m
TcTc-tilmanocept lymphoscintigraphy in 20% of patients. Of the 33 SLNs identified by
68
GaGa-tilmanocept PET/CT lymphoscintigraphy, 30 (91%) were intraoperatively localized under conventional gamma-probe guidance.
Conclusion
68
GaGa-tilmanocept PET/CT lymphoscintigraphy provided more accurate identification of SLNs and improved visualization of lymphatic vessels compared to
99m
TcTc-tilmanocept lymphoscintigraphy. When combined with peritumoral administration of
99m
TcTc-tilmanocept, SLNs detected by
68
GaGa-tilmanocept PET/CT lymphoscintigraphy can be reliably localized during surgery under conventional gamma-probe guidance.
Purpose
To evaluate whether quantitative
18
FFDG-PET/CT assessment, including radiomic analysis of
18
FFDG-positive thyroid nodules, improved the preoperative differentiation of indeterminate ...thyroid nodules of non-Hürthle cell and Hürthle cell cytology.
Methods
Prospectively included patients with a Bethesda III or IV thyroid nodule underwent
18
FFDG-PET/CT imaging. Receiver operating characteristic (ROC) curve analysis was performed for standardised uptake values (SUV) and SUV-ratios, including assessment of SUV cut-offs at which a malignant/borderline neoplasm was reliably ruled out (≥ 95% sensitivity).
18
FFDG-positive scans were included in radiomic analysis. After segmentation at 50% of SUV
peak
, 107 radiomic features were extracted from
18
FFDG-PET and low-dose CT images. Elastic net regression classifiers were trained in a 20-times repeated random split. Dimensionality reduction was incorporated into the splits. Predictive performance of radiomics was presented as mean area under the ROC curve (AUC) across the test sets.
Results
Of 123 included patients, 84 (68%) index nodules were visually
18
FFDG-positive. The malignant/borderline rate was 27% (33/123). SUV-metrices showed AUCs ranging from 0.705 (95% CI, 0.601–0.810) to 0.729 (0.633–0.824), 0.708 (0.580–0.835) to 0.757 (0.650–0.864), and 0.533 (0.320–0.747) to 0.700 (0.502–0.898) in all (
n
= 123), non-Hürthle (
n
= 94), and Hürthle cell (
n
= 29) nodules, respectively. At SUV
max
, SUV
peak
, SUV
max
-ratio, and SUV
peak
-ratio cut-offs of 2.1 g/mL, 1.6 g/mL, 1.2, and 0.9, respectively, sensitivity of
18
FFDG-PET/CT was 95.8% (95% CI, 78.9–99.9%) in non-Hürthle cell nodules. In Hürthle cell nodules, cut-offs of 5.2 g/mL, 4.7 g/mL, 3.4, and 2.8, respectively, resulted in 100% sensitivity (95% CI, 66.4–100%). Radiomic analysis of 84 (68%)
18
FFDG-positive nodules showed a mean test set AUC of 0.445 (95% CI, 0.290–0.600) for the PET model.
Conclusion
Quantitative
18
FFDG-PET/CT assessment ruled out malignancy in indeterminate thyroid nodules. Distinctive, higher SUV cut-offs should be applied in Hürthle cell nodules to optimize rule-out ability. Radiomic analysis did not contribute to the additional differentiation of
18
FFDG-positive nodules.
Trial registration number
This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014),
https://clinicaltrials.gov/ct2/show/NCT02208544
.
Purpose
Sentinel lymph node (SLN) biopsy has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC).
99m
TcTc-tilmanocept may be of benefit in OSCC ...with complex lymphatic drainage patterns and close spatial relation to SLNs.
Methods
A prospective within-patient evaluation study was designed to compare
99m
TcTc-tilmanocept with
99m
TcTc-nanocolloid for SLN detection. A total of 20 patients with early-stage OSCC were included, who underwent lymphoscintigraphy with both tracers. Both lymphoscintigraphic images of each patient were evaluated for SLN detection and radiotracer distribution at 2–4 h post-injection.
Results
The injection site’s remaining radioactivity was significantly lower for
99m
TcTc-tilmanocept (29.9%), compared with
99m
TcTc-nanocolloid (60.9%;
p
< 0.001). Radioactive uptake in SLNs was significantly lower for
99m
TcTc-tilmanocept (1.95%) compared with
99m
TcTc-nanocolloid (3.16%;
p
= 0.010). No significant difference was seen in SLN to injection site ratio in radioactivity between
99m
TcTc-tilmanocept (0.066) and
99m
TcTc-nanocolloid (0.054;
p
= 0.232). A median of 3.0 and 2.5 SLNs were identified with
99m
TcTc-tilmanocept and
99m
TcTc-nanocolloid, respectively (
p
= 0.297). Radioactive uptake in higher echelon nodes was not significantly different between
99m
TcTc-tilmanocept (0.57%) and
99m
TcTc-nanocolloid (0.86%) (
p
= 0.052). A median of 2.0 and 2.5 higher echelon nodes was identified with
99m
TcTc-tilmanocept and
99m
TcTc-nanocolloid, respectively (
p
= 0.083).
Conclusion
99m
TcTc-tilmanocept had a higher injection site clearance, but at the same time a lower uptake in the SLN, resulting in an SLN to injection site ratio, which was not significantly different from
99m
TcTc-nanocolloid. The relatively low-radioactive uptake in SLNs of
99m
TcTc-tilmanocept may limit intraoperative detection of SLNs, but can be overcome by a higher injection dose.
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