Ruolo della PET/CT
dott. F. Giunta
18F-FDG PET/CT
❖ 18F-FDG tracciante positivo di glicolisi
❖ PET/CT imaging ibrido
Abdom Imaging. 2008 Jan-Feb;33(1):112-8.
PET-CT vs. CT alone in ovarian cancer recurrence.
Sebastian S1, Lee SI, Horowitz NS, Scott JA, Fischman AJ, Simeone JF, Fuller AF, Hahn PF.
BACKGROUND:
To compare fusion, positron emission tomography-computed tomography (PET-CT) with CT alone in detecting ovarian carcinoma recurrence.
METHODS:
Fifty-one consecutive patients underwent 53 restaging PET-CT scans with a concurrent diagnostic quality CT scan. Two body imaging radiologists independently assessed the CT's; each then teamed with a nuclear medicine specialist to review the PET-CT's. Two
teams conferred for consensus on the presence of disease in the chest, abdomen, and body overall with CT alone and with PET-CT, using a six-point reader confidence metric to determine accuracy and receiver operating characteristic (ROC) curves. Reader
agreement was compared using kappa. Recurrence was determined by two gynecologic oncologists reviewing clinical records from time of presentation to at least 13 months (mean 22.7) after imaging.
RESULTS:
Recurrence was based on histopathology in 17% (9/53). Seventy-two percent (38/53) cases had recurrence, with two cases showing isolated chest recurrence. PET-CT accuracy exceeded CT for body 92% (49/53) vs. 83% (44/53), chest 96% (51/53) vs. 89% (47/53), and abdomen 91% (48/53) vs. 79% (42/53). ROC curves for PET-CT dominated that for CT alone; this difference was statistically significant for abdomen and for body overall (P < 0.01). Interobserver agreement was better for PET-CT than for CT alone.
CONCLUSIONS:
PET-CT demonstrates greater accuracy and less interobserver variability than CT alone.
Better accuracy of PET-CT vs. CT alone in the restaging
setting
Gynecol Oncol. 2007 Apr;105(1):17-22. Epub 2007 Jan 10.
Clinical use of combined positron emission tomography and computed tomography (FDG-PET/CT) in recurrent ovarian cancer.
Thrall MM1, DeLoia JA, Gallion H, Avril N.
OBJECTIVE:
The aim of this study was to evaluate the use of co-registered PET/CT using F-18 fluorodeoxyglucose (FDG) for surveillance and follow-up of ovarian cancer patients to detect recurrent disease.
MATERIAL AND METHODS:
A retrospective chart review was performed on 39 ovarian cancer patients who underwent a total of 59 FDG-PET/CT scans. The following information was obtained: clinical indication for FDG-PET/CT, the results of FDG-PET/CT particularly with regard to the additional diagnostic information, the localization of disease and subsequent clinical patient management.
RESULTS:
Twenty-four FDG-PET/CT were performed in 22 patients with previously negative or indeterminate CT scans but rising CA-125 levels providing a sensitivity of 90% for localizing disease. Nine FDG-PET/CT in 8 patients with clinical symptoms of recurrence but normal CA-125 levels
detected all three patients who had recurrent disease confirmed within 6 months of follow-up. In addition, 4 FDG-PET/CT performed as routine follow-up with no clinical evidence of recurrent disease were true-negative in all cases. Fourteen FDG-PET/CT in 12 patients with recurrent disease already identified by conventional CT imaging were useful in guiding treatment decisions such as radiation therapy, surgery or
chemotherapy by confirming the recurrence and more precisely localizing the site(s) of disease. Of note, FDG-PET/CT helped to avoid surgery in four patients who had additional disease detected in unresectable anatomic areas. A total of 51 FDG-PET/CT were performed in the patients described above with an overall sensitivity and specificity of 94.5% and 100%, respectively. Eight FDG-PET/CT scans in five patients
performed for assessment of treatment response following chemotherapy or radiation were useful as the disease was not clearly visualized by conventional CT imaging at baseline.
CONCLUSIONS:
In our experience, FDG-PET/CT has the greatest utility in settings of suspected ovarian cancer recurrence, particularly in patients with rising CA-125 levels and negative conventional imaging. FDG-PET/CT was specifically helpful in
optimizing the selection of patients for site-specific treatment, including radiation treatment planning, and aided in the selection of optimal surgical candidates. The co-registered metabolic-anatomic information from combined FDG-PET/CT holds promise in replacing the single imaging procedures.
Best accuracy with rising CA-125 levels and inconclusive CT or MRI
Eur J Radiol. 2009 Jul;71(1):164-74. doi: 10.1016/j.ejrad.2008.02.019. Epub 2008 Apr 18.
CA 125, PET alone, PET-CT, CT and MRI in diagnosing recurrent ovarian carcinoma: a systematic review and meta- analysis.
Gu P1, Pan LL, Wu SQ, Sun L, Huang G.
BACKGROUND AND PURPOSE:
Ovarian cancer is the commonest tumor in female patients with a propensity for recurrence even after primary chemotherapy in early stage. The accuracy of CA 125, PET alone, PET-CT, CT and MRI in diagnosing the recurrent ovarian carcinoma has never been systematically assessed, and present systematic review was aimed at this issue.
METHODS:
We searched for articles published from January 1995 to November 2007, inclusion criteria including: articles were reported in English or Chinese; CA 125, PET whether interpreted with or without the use of CT, CT or MRI was used to detect recurrent ovarian carcinoma; Histopathologic analysis and/or close clinical and imaging follow-up for at least 6 months. We extracted data to calculate sensitivity, specificity, SROC curves and AUC and to test for heterogeneity.
RESULT:
In 34 included studies, CA 125 had the highest pooled specificity, 0.93 (95% CI: 0.89-0.95); PET-CT had highest pooled sensitivity, 0.91 (95% CI:
0.88-0.94). The AUC of CA 125, PET alone, PET-CT, CT and MRI were 0.9219, 0.9297, 0.9555, 0.8845 and 0.7955, respectively. Results of pairwise comparison between each modality demonstrated AUC of PET, whether interpreted with or without the use of CT, was higher than that of CT or MR, p<0.05. The pooled sensitivity, pooled specificity and AUC showed no statistical significance between PET alone and PET-CT. There was heterogeneity among studies and evidence of publication bias.
CONCLUSION:
PET-CT might be a useful supplement to current surveillance techniques, particularly for those patients with an increasing CA 125 level and negative CT or MR imaging. However, regarding to diagnostic accuracy, interpreted CT images may have limited additional value on PET in detecting recurrent ovarian cancer.
Best accuracy with rising CA-125 and inconclusive CT or MRI
Nucl Med Commun. 2008 Dec;29(12):1046-51. doi: 10.1097/MNM.0b013e32831089cb.
18F-FDG PET/CT evaluation of patients with ovarian carcinoma.
Iagaru AH1, Mittra ES, McDougall IR, Quon A, Gambhir SS.
PURPOSE:
The role of F-FDG PET has been studied in ovarian carcinoma, but its sensitivity and specificity calculations are based on dedicated PET acquisition, not PET/CT in the majority of the published studies. Therefore, we were prompted to review our experience with PET/CT in the management of patients with ovarian carcinoma.
MATERIALS AND METHODS:
This is a retrospective study of 43 women with ovarian carcinoma, 27-80 years old (average: 53.9+/-7.8), who had whole-body PET/CT at our institution from 1 January 2003 to 31 August 2006. We reviewed the patients' outcomes from medical records and compared them to the interpretation of the PET/CT scans.
Sensitivity and specificity were calculated using a 2 x 2 table with pathology results (79.1% of the patients) or clinical follow-up (20.9% of the cases) as the 'gold standard'. Confidence interval (CI) estimations were performed using the Wilson score method.
RESULTS:
All patients had advanced stage ovarian cancer and the study was requested for re-staging. A total of 60 scans were performed: 30 patients had one scan, nine patients had two scans and four patients had three scans. The administered doses of F-FDG ranged from 381.1 to 769.6 MBq (average: 569.8+/-73.3). PET/CT had a sensitivity of 88.4% (95% CI: 75.1-95.4) and a specificity of 88.2% (95% CI: 64.4-97.9) for detection of ovarian cancer. The SUV max of the detected lesions ranged from 3 to 27 (average: 9.4+/-5.9). The CA-125 tumor marker ranged from 3 to 935 kU/ml (average: 265.2) in patients with positive scans and 4-139 kU/ml (average: 17.1) in patients with negative scans. This difference was statistically significant (P value: 0.0242).
CONCLUSION:
This study confirms the good results of F-FDG PET/CT for identification of residual/recurrent ovarian cancer, as well as for distant metastases localization. PET/CT should be an integral part in evaluation of patients with high-risk ovarian cancer or rising values of tumor markers
(CA-125), prior to selection of the most appropriate therapy.
Better SE in extrapelvic sites
Radiology. 2004 Nov;233(2):433-40.
Integrated FDG PET/CT in patients with persistent ovarian cancer: correlation with histologic findings.
Sironi S1, Messa C, Mangili G, Zangheri B, Aletti G, Garavaglia E, Vigano R, Picchio M, Taccagni G, Maschio AD, Fazio F .
PURPOSE:
To prospectively evaluate the accuracy of integrated positron emission tomography (PET) and computed tomography (CT) for depiction of persistent ovarian carcinoma after first-line treatment, with use of histologic findings as the reference standard.
MATERIALS AND METHODS:
Thirty-one women (mean age, 55.9 years) with ovarian carcinoma treated with primary cytoreductive surgery and followed up with platinum regimen chemotherapy were included. All 31 patients were scheduled for surgical second-look. Before surgical second-look, all patients underwent fluorodeoxyglucose (FDG) PET/CT. At PET/CT, three main categories of persistent disease were considered for data analysis: lymph nodal lesion, peritoneal lesion, and pelvic lesion. In all patients, imaging findings were compared with results of histologic examination after surgical second-look to determine the diagnostic accuracy of PET/CT in the evaluation of disease status.
The kappa statistic (Cohen kappa) was used for statistical analysis.
RESULTS:
Seventeen (55%) of 31 patients had persistent tumor at histologic analysis after surgical second-look, and fourteen (45%) had no histologically proved tumor. The total number of lesions that was positive for tumor cells at histologic analysis was 41 (lymph nodes, n
= 16; peritoneal lesions, n = 21; pelvic lesions, n = 4); maximum diameter of these lesions was 0.3-3.2 cm (mean, 1.7 cm). A correlation was found between PET/CT and histologic analysis (kappa = 0.48). The overall lesion-based sensitivity, specificity,
accuracy, positive predictive value, and negative predictive value of PET/CT were 78%, 75%, 77%, 89% and 57%, respectively.
In the detection of a tumor, a size threshold could be set at 0.5 cm, as this was the largest diameter of a lesion missed at PET/
CT.
CONCLUSION:
Integrated PET/CT depicts persistent ovarian carcinoma with a high positive predictive value.
Low SE and NPV in microlesions
5 mm!!!
Oncology. 2008;75(3-4):152-8. doi: 10.1159/000159266. Epub 2008 Oct 1.
A treatment selection protocol for recurrent ovarian cancer patients: the role of FDG-PET/CT and staging laparoscopy.
Fagotti A1, Fanfani F , Rossitto C, Lorusso D, De Gaetano AM, Giordano A, Vizzielli G, Scambia G.
OBJECTIVE:
To investigate the best diagnostic and staging strategy for recurrent ovarian cancer.
METHODS:
The negative predictive value, specificity, positive predictive value, sensitivity, and accuracy rates of the fluorine-18-fluorodeoxyglucose positive emission tomography computed tomography (FDG-PET/CT) and staging laparoscopy in identifying surgically treatable/untreatable patients are assessed in a consecutive series of 70 recurrent ovarian cancer cases. Moreover, the diagnostic performance of each staging procedure in the evaluation of the number of nodules is analyzed.
RESULTS:
The negative predictive value of the FDG-PET/CT was 83.3%, whereas the positive predictive value was 76.9%. Specificity was 55.6%, whereas sensitivity was 93.0%. Accuracy rate was 78.6%. Negative predictive value, specificity, positive predictive value, sensitivity, and accuracy rate of staging laparoscopy were 88.9, 64.0, 80.8, 95.0 and 83.1%, respectively.
Combined radiological and laparoscopic evaluation showed a negative predictive value of 88.9%, a specificity of 59.3%, a positive predictive value of 78.8%, a sensitivity of 95.3%, and an accuracy rate of 81.4%. The number of nodules identified by FDG-PET/CT corresponded in only 23 patients (40.3%) at laparotomy, whereas 15 of 30 patients were correctly diagnosed (50.0%) by staging
laparoscopy.
CONCLUSIONS:
The combination of FDG-PET/CT and staging laparoscopy has a significant effect on the multimodal approach to the
population of patients with recurrent ovarian cancer. Such techniques should be considered complementary, because of the potential of each one to identify a different setting of the disease.
Low SE and NPV for micro lesions
false negatives at PET were
lesions less than 7mm
Eur J Nucl Med Mol Imaging. 2008 Aug;35(8):1439-48. doi: 10.1007/s00259-008-0776-3. Epub 2008 Apr 17.
Performance of integrated FDG-PET/contrast-enhanced CT in the diagnosis of recurrent ovarian cancer:
comparison with integrated FDG-PET/non-contrast-enhanced CT and enhanced CT.
Kitajima K1, Murakami K, Yamasaki E, Domeki Y , Kaji Y , Fukasawa I, Inaba N, Suganuma N, Sugimura K.
PURPOSE:
The aim of this study was to evaluate the accuracy of integrated positron emission tomography and computed tomography (PET/CT) using (18)F-fluorodeoxyglucose with IV contrast for depiction of suspected recurrent ovarian cancer and to assess the impact of PET/
contrast-enhanced CT findings on clinical management, compared with PET/non-contrast-enhanced CT and CT component.
METHODS:
One hundred thirty-two women previously treated for ovarian cancer underwent PET/CT consisting of non-enhanced and contrast- enhanced CT for suspected recurrence. PET/contrast enhanced CT, PET/non-contrast-enhanced CT, and enhanced CT were interpreted by two experienced radiologists by consensus for each investigation. Lesion status was determined on the basis of histopathology, radiological imaging, and clinical follow-up for longer than 6 months.
RESULTS:
Patient-based analysis showed that the sensitivity, specificity, and accuracy of PET/contrast-enhanced CT were 78.8% (52 of 66), 90.9% (60 of 66), and 84.8% (112 of 132), respectively, whereas those of PET/non-contrast-enhanced CT were 74.2% (49 of 66), 90.9% (60 of 66), and 82.6% (109 of 132), respectively, and those of enhanced CT were 60.6% (40 of 66), 84.8% (56 of 66), and
72.7% (96 of 132), respectively. Sensitivity, specificity, and accuracy differed significantly among the three modalities (Cochran Q test:
p = 0.0001, p = 0.018, and p < 0.0001, respectively). The findings of PET/contrast-enhanced CT resulted in a change of management for 51 of the 132 patients (39%) and had an effect on patient management in 16 patients (12%) diagnosed by enhanced CT alone and three patients (2%) diagnosed by PET/non-contrast-enhanced CT.
CONCLUSION:
Integrated PET/contrast-enhanced CT is an accurate modality for assessing ovarian cancer recurrence and led to changes in the subsequent appropriate therapy.
Advantage of PET-CECT
Gynecol Oncol. 2006 Oct;103(1):271-6. Epub 2006 Apr 19.
The impact of PET/CT in the management of recurrent ovarian cancer.
Simcock B1, Neesham D, Quinn M, Drummond E, Milner A, Hicks RJ .
OBJECTIVES:
To evaluate the impact of PET/CT on the restaging and management of recurrent ovarian cancer.
METHODS:
From January 2002 to July 2003, all women undergoing either surveillance or investigation of possible recurrent ovarian cancer at the Centre for Molecular Imaging, The Peter MacCallum Cancer Centre, were invited to take part in a prospective evaluation of the clinical impact of PET/
CT.
RESULTS:
Fifty-six women having 66 scans were available for analysis.
All patients had at least 12months follow-up after the PET/CT unless they died before that time. Apart from one equivocal scan, all scans performed in women with a CA125 higher than 35IU/ml had a positive PET/CT. PET/CT altered the known disease distribution in 40 scans (64%). Overall, PET/CT showed less disease in six scans (9%) and more disease in 34 scans (52%). Regardless of the value of CA125, PET/CT identified a sub group of women with apparently localized disease or no definite evidence of disease. This group showed improved survival compared with women shown to have systemic disease.PET/CT resulted in a major change of management plan in 34 patients (58%).
CONCLUSION:
PET/CT modifies the assessment of the distribution of recurrent ovarian cancer and alters patient management in a substantial proportion of patients. PET/CT appears to offer prognostic information.
Change of management managemen Change of
t in
58% of pts
18F-FDG PET-CT in Recurrent Cervical Cancer
249 patients previously treated for cervical cancer
Detection of recurrence:
SE: 90%
SP: 76%
high FP rate
patien
ts were asym
ptomatic early
recurrence PET, not PET/
CT
Gynecol Oncol. 2007 Mar;104(3):529-34. Epub 2006 Oct 16.
Clinical impact of integrated PET/CT on the management of suspected cervical cancer recurrence.
Chung HH1, Jo H, Kang WJ, Kim JW, Park NH, Song YS, Chung JK, Kang SB, Lee HP.
OBJECTIVES:
To assess the value and clinical impact of integrated PET/CT using (18)F-FDG in the diagnosis and management of women with suspected cervical cancer recurrence.
Retrospective, 52 patients
SE: 90% SP:81% Acc:86%
neg PET/CT: 2yrPrognostic value:s disease free survival: 85%
pos PET/CT: 2yr
s disease free survival: 10%
Sarker et al (metaanalysis 1150 pts)
Clin Nucl Med. 2015 Oct 23 ePub. (in staging setting
)
Change of management 23%
CONCLUSIONS:
In patients with a suspected recurrence of cervical cancer, integrated PET/CT using (18)F-FDG provides good anatomic and functional localization of suspicious lesions, and the better diagnostic interpretation has an impact not only on clinical management and treatment planning of patients, but also on disease-free survival.
Pte 63 anni
Ca squamoso cervice uterina Trattata con CT-RT
Ristadiazione per evidenza di reperti dubbi alla TC (nodulazioni in sede
mesenteriale, celiaca, iliaca comune sx)
FDG PET/TC:
assenza di reperti ipermetabolici
Tumori della cervice uterina RISTADIAZIONE
Tumori della cervice uterina RISTADIAZIONE
Pte 38 anni
Ca squamoso cervice uterina Trattata con chirurgia esclusiva (Stadio IA1)
Ristadiazione per comparsa di dolore all’arto inf sx ed edema.
Presenza alla TC di tessuto solido disomogeneo a livello dei vasi iliaci interni
FDG PET/TC:
Anomalo accumulo di radiofarmaco in sede iliaca int sx, in corrispondenza del reperto TC.
Non ulteriori localizzazioni.
Tumori della cervice uterina RISTADIAZIONE
Pte 72 anni
Ca squamoso cervice uterina Trattata con CT-RT
Ristadiazione per incremento dei markers tumorali
FDG PET/TC:
Plurime adenopatie iperfissanti in sede ilare epatica,
peripancreatica, retrocrurale,
pre- e retrocavale, interaortocavale e lomboaortica bilaterale
Ulteriore focalità in ambito epatico
(S6)
10.2 Detection of relapsed disease
Annex 7 shows an algorithm for the detection of relapsed disease.
CT or MRI is more easily available, cheaper and in symptomatic patients is better than PET at differentiating metastatic complications from post-treatment complications,177 for example, insufficiency fractures of the pelvis.
There is some evidence supporting the use of intravenous contrast in post-therapy MRI scans in symptomatic and asymptomatic patients to differentiate fibrosis post-radiotherapy from recurrent tumour.56 There is evidence from a small study (19 patients) that PET-CT scans may be more accurate than either postcontrast CT or MRI in differentiating post-treatment fibrosis from recurrent disease.178 Evidence level 2++
A whole body PET or PET-CT scan is a sensitive post-therapy surveillance modality for the detection of recurrent and persistent cervical carcinoma in both asymptomatic and symptomatic patients.64,81,179-181 Evidence level 2++, 2+, 4
There is little evidence to support the optimal timing or frequency of post-therapy scans.179 In several studies whole body PET scans were generally performed no sooner than three months post primary treatment to avoid false positives associated with post-surgical or radiotherapy oedema or inflammatory response in the pelvis. A PET scan at nine months would be expected to detect the majority of recurrences, whether or not patients are symptomatic.181-183 Recurrence may still occur before and after nine months, but rarely after 30 months. A study of 152 patients showed that early persistent post-therapy fdg-PET uptake may be predictive of tumour recurrence and death from cervical cancer.182 Evidence level 2++
PET is more accurate in the detection of metastatic or nodal disease than CT or MRI.81 At the time of publication PET-CT imaging combined is the modality of choice rather than PET scans alone. CT, CT-PET or MRI are more accurate in the detection of recurrent disease than clinical examination alone. Evidence level 2++
If fdg-PET uptake is positive only in the pelvis and cross-sectional imaging has not been performed, CT or MRI is still required to assess resectibility.64,85 Evidence level 2++
If performed prior to pelvic exenteration, a whole body PET or PET-CT scan can improve selection of operable patients and potentially improve their survival rates,180,184 and can eliminate unnecessary morbidity associated with salvage procedures in unsuitable patients.180,181,184,185 Evidence level 2++, 2+
There is no evidence to demonstrate that prior radiotherapy or chemotherapy alters the sensitivity of detection of recurrence.
C
MRI or CT should be considered initially to assess potential clinical recurrence in symptomatic patients.
B
A whole body PET scan or PET-CT should be performed on all patients in whom recurrent or persistent disease has been demonstrated on MRI or CT and in whom salvage therapy (either pelvic exenteration or radiotherapy) is being considered.
A PET-CT scan at nine months of follow up is recommended in women who have had chemoradiotherapy.
SIGN 99: MANAGEMENT OF CERVICAL CANCER
