primary (CUP) syndrome

Transcription

1 Role of whole body magnetic resonance imaging with diffusion weighted imaging sequences (DWIBS) vs computed tomography-positron emission tomography (CTPET) in evaluation of patients with carcinoma of unknown primary (CUP) syndrome Poster No.: C-0775 Congress: ECR 2012 Type: Scientific Paper Authors: A. Cassarà, L. E. Guerra, S. Delli Passeri, M. Peveroni, M. Lombardi, E. Innamorato, A. Stecco, A. Carriero; Novara/IT Keywords: Oncology, MR-Diffusion/Perfusion, PET-CT, Imaging sequences, Metastases, Neoplasia DOI: /ecr2012/C-0775 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 14

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3 Purpose We have conducted a pilot study in order to evaluate the diagnostic accuracy of Whole Body- Diffusion-Weighted Imaging with Background body signal Suppression (WBDWIBS) in the detection of primary tumor in patients with Carcinoma of Unknown Primary (CUP) syndrome, who underwent the reference methods, represented by whole-body 18 Fluorodeoxyglucose Positron Emission Tomography - Computed Tomography (PETCT). Page 3 of 14

4 Methods and Materials We enrolled 20 consecutive patients that already underwent a PET-CT evaluation subsequent to the finding of a metastatic localization confirmed by cyto-histology, as inclusion criteria. All patients were studied with a superconducting 1.5 T MRI (Achieva, Philips, Best, Netherlands, release 2.1). We used the q-body coil, placing the patient "feet first", with a caudo-cranial entry in the gantry, with a table-patient with an anatomical coverage, based on the technology of the mobile table (MobiTrak, Philips). The focus was on the orbitomeatal plane. After a centering sequence, we acquired a DWIBS sequence (STIR Echo Planar, single shot) in the axial plane, repeated on at least continuous 4 stacks to cover all anatomical districts from head to femurs in order to trace the anatomical coverage of PET-CT and thus make the two methods comparable. The sequence was weighted with a double value of b (b = 0 and b = s/mm2 1000), using only the second for the reports. In this pilot study were also acquired conventional MRI sequences (such asse T1 and STIR) whole-body in addition to diffusion-weighted imaging. The acquisition time of this protocol was approximately 45 minutes for each individual patient. MIP rotational reconstructions were subsequently processed and MPR in coronal and sagittal plane were reconstructed as well. We applied Fisher and McNemar tests to evaluate the diagnostic accuracy of each methods in comparison with histology, considered as the gold standard, and to evaluate if the WB-MRI could be a better diagnostic procedure than the PET-CT. Furthermore sensitivity and specificity were obtained. Page 4 of 14

5 Results The analysis of our study showed that PET-CT is not always able to identify correctly the site of the tumor. WB-DWIBS identified primary lesions in 17/20 patients. In 3 cases WB-MRI resulted negative while PET-CT was positive: - A patient had a little pulmonary node site in the right parahilar field visualized with PETCT and was reported as an aspecific lymphoadenopathy by the WB-DWIBS. - A patient with a breast USexamination positive for an area of structural inhomogeneity in the upper-outer quadrant of the left breast. This finding in WB-MRI examination was interpreted as site of phlogosys because of the diffusion signal weakness while in the PET-CT investigation was detected a focal uptake highly suspect. - A patient, that showed in the PET-CT examination an abnormal uptake in the outer quadrants of the right breast, while in the WB-MRI examination no altered diffusion signal in that area was shown, was later histologically framed as anhidrosadenitis. In 4 cases we saw a perfect agreement between the two methods ( 1 larynx cancer, 2 lung cancer 2, and 1 true negative ); 6 were identified exclusively with the DWIBS (1 Krukenberg tumor, 1 testicular Seminona 1, 2 breast cancer, 2 liver cancer ), the 7 remaining cases remained true to the current CUP syndrome standards. Sensitivity and specificity are higher in DWIBS (100% and 90,9% vs 66,7% and 57%) as diagnostic accuracy (95% vs 60%) (table 1 and 2). In patients with positive histology the comparison of sensitivity between two methods (Fisher' test) was 0.06, instead in patients with negative histology the comparison of specificity (Fisher' test) was As the p-value was > 0.05, the difference has been considered not statistically significant. Not covered by the study design, but still of interest, we have researched the different detection ability of incidental lesions, those not attributable to a primary tumor (Figure 4 and Figure 5). When the lesion is too much little, WB-DWI is not always able to identify it (Figure 6). Page 5 of 14

6 Images for this section: Fig. 1: 47 years old female. PET-CT was negative (a) and WB-DWIBS demonstrated altered restriction in the right breast (b) and in a little axillary limphnode (c). The cytohistologic diagnosis was of infiltrating ductal carcinoma. Page 6 of 14

7 Fig. 2: 70 years old male. PET-CT demonstrated retroperitoneal limphnodes (a, b) and WB-DWIBS demonstrated areas of altered restriction at the lumbo-aortic lymph nodes, iliac and inguinal (c, d). The primary tumor was identified only at DWIBS and the cytohistologic diagnosis was testicular seminoma. Page 7 of 14

8 Fig. 3: 63 year old female. PET-CT positive only for the left supraclavicular lymph node and small axillary lymph nodes. DWIBS revealed areas of altered restriction even in the stomach, colon, mesentery and abdominal wall and at rachis. Moreover both ovaries and the inferior-medial wall of the uterus. These findings are consistent with metastatic spread of tumor departure from gastro-intestinal tract, so-called Krukenberg tumor confirmed at cyto-histologic diagnosis. Page 8 of 14

9 Table 1: PET-CT vs Gold standard (histology) Table 2: DWIBS vs Gold standard (histology) Page 9 of 14

10 Fig. 4: 70 years old male. DWIBS and PET-CT were both positive for altered restriction of the signal/uptake at the right VI rib and sternum, the latter identified only with DWI. Fig. 5: 49 years old female. Epatic lesions revealed only by WB-DWIBS in patient with breast cancer. Page 10 of 14

11 Fig. 6: 70 years old male. PET-CT positive for abnormal FDG uptake at the right adrenal gland. Page 11 of 14

12 Conclusion Nowadays WB-DWIBS is not able to replace the current PET-CT yet, but might become a possible reference imaging protocol for detection of the primitive tumors. This study is work in progress. Page 12 of 14

13 References 1. Bonadonna G,Robustelli della Cuna G(1994) Medicina oncologica, V edizione cap 55: Kwee TC, Kwee RM (2009) Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis. Eur Radiol 19: Kwee TC, Takahara T, Ochiai R et al (2008) Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS): features and potential applications in oncology. Eur Radiol 18(9): Pavlidis N, Fizazi K (2009) Carcinoma of unknown primary (CUP). Crit Rev Oncol Hematol 69: Pentheroudakis G, Briasoulis E, Pavlidis N (2007) Cancer of unknown primary site: missing primary or missing biology? Oncologist 12: Kwee TC, Takahara T, Ochiai R et al (2007) Complementary roles of wholebody diffusion-weighted MRI and 18F-FDG PET: the state of the art and potential applications. J Nucl Med 51(10): Nassenstein K, Veit-Haibach P, Stergar H et al (2007) Cervical lymph node metastases of unknown origin: primary tumor detection with wholebody positron emission tomography/computed tomography. Acta Radiol 48: Takahara T, Imai Y, Yamashita T et al (2006) Diffusion weighted whole body imaging with background body signal suppression (DWIBS): technical improvement using free breathing, STIR and high resolution 3D display. Radiat Med 22: Eustace S, Tello R, Decarvalho V et al (1997) A comparison of whole-body turbo short tau inversion recovery MR imaging and plan technetium 99m methylene diphosphonate scintigraphy in the evaluation of patients with suspected skeletal metastases. AJR Am J Roentgenol 169: Tai-fu Gu, Xin-lan Xiao, Fei Sun, Jian-hua Yin, Hai Zhao (2008) Diagnostic value of whole body diffusion weighted imaging for screening primary tumors of patients with metastases. Chinese Medical Sciences Journal 23,3: Page 13 of 14

14 Personal Information Page 14 of 14