Esophageal Cancer: A Multimodality Approach to Detection and Staging, MBA Topic: Esophageal Cancer Imaging: A multimodality approach Conference: Society of Thoracic Imaging Location: Date/Time: March 14, 2014 14:00-14:20 Prepared & Presented by: Appreciation Note: Society of Thoracic Radiology (STR-2014) Scientific Committee Financial Disclosure: I have received no financial support in preparation p of this presentation. CME Objectives: 1. of role of PETCT in the initial work-up and subsequent management of Esophageal cancer., MBA Visiting Clinical Professor of Diagnostic Radiology & Nuclear Medicine University of California Davis Medical Center Sacramento, California Diagnostic Medical Imaging (DMI) Sutter Medical Group (SMG) Sacramento, California 2. Discussing limitations, technical issues and pitfalls, related to hybrid imaging in oncologic application of PETCT in Esophageal malignancies. 3. An update on current literature, comparing PETCT with CECT (contrast enhanced CT), MRI and EUS (Endoscopic Ultrasound). : Esophageal Cancer : Esophageal Cancer : Esophageal Cancer 2 min 10 min Radiation Therapy Planning 2 min 3 min Restaging & Recurrence 3 min : Esophageal Cancer: : Esophageal Cancer: US incidence: 1 in 200 ACC > SCC Worldwide: 10-100 x of US SCC > ACC 2 main subtypes: Location: Predisposing factor: Squamous cell carcinoma: Upper 2/3 rd Tobacco & Alcohol Adenocarcinoma: Lower 1/3 rd Reflux & Barrett's Poor 5 year survival (=5YS) Advanced at the time of Dx Main M i survival lfactor: Extent tat tthe time of fdx Confined: 5YS= 37 % Regional: 17 % Distant: 3 % Sensitivity for detecting the primary tumor: PET alone: 70-100% FNs: Small tumors (T1 -<5-8mm) CT alone: 65-90% Uptake values: Wieder et al-2011 Dehdashti &Siegel- 2004 Adenoca = Squamous CA Cannot be distinguished by SUVs Higher overall uptake: Worse prognosis SUV has prognostic value Supporting papers: Kato et al-2009 / Pan et al-2009 / Shenfine et al-2009 / Chez-Le rest et al-2008 Contradictory papers: Rizk et al-2009 / van Westreenen et al-2005 / Hatt et al-2011 407
: Esophageal Cancer: : Esophageal Cancer: Accuracy for staging: PET alone: 83% PETCT: 90% Specificity for staging: PET alone: 59% PETCT: 81% CT alone: Accuracy T-staging: 40-60% 40-75% 33% have occult metastasis CT provides info on: Wall thickening Mediastinal invasion/involvement Regional nodes Liver/lung/adrenal / d l/distant nodal l/ /peritoneal mets 1. T-staging: g No distal esophageal wall thickening + Hyper-metablic foci 2. Normal size node (CT) + Hyper-metabolism 3. No liver lesion seen on CT + Hyper-metabolic foci Yuan et al Jadvar et al PET alone: Detects almost 100% of esophageal cancers PET & CT: Limited sensitivity for regional (adjacent) node detection: marked activity of nearby primary focus Potential advantage of PETCT specificity over CT: Enlarged nodes with no activity (avoiding FP of CT)! PETCT is more accurate than CT for distant metastasis Clinical point: Regional nodes are resectable at surgery. Positive regional node doesnt preclude curative resection PETCT is not good dfor regional node detection: Who cares! PETCT is accurate for distant met detection: Which matters! : Esophageal Cancer: Distant met assessment: Accuracy PET: 80% PET- CT: 90% Some are hot but not big, some are big but not hot! : Esophageal Cancer: T-staging: Depends on Nuclear Grade Size Local extension Tis: In situ T1: Confined to Mucosa/Submucosa T2: Confined to Muscularis Propria T3: Adventitia Invasion T4: Nearby organ invasion PETCT changes the management in 22% over CT alone and PET alone: Finding CT anomalies after reviewing PET images! Better localization of PET activities Guiding endoscopy Preventing subsequent work ups with PET and CT PETCT contraindications to curative (radical) surgery: Liver Lung Bone Supraclavicular LN Peritoneal mets N0: No regional node N1: Regional node All other Ns are actually M1! M1a: Liver(35%) Lung(20%) Bone (9%) Peritoneal (2%) : Esophageal Cancer: : Esophageal Cancer: Definition of local node (N1): For Upper-esophageal esophageal cancer (cervical) Scalenous Internal Jugular Supraclavicular (M1b if T@Mid Thorax: Super poor prognosis) For Mid-esophageal cancer (Intra-thoracic) thoracic) Peri-esophageal Subcarinal Usually (75%) nodal spread is one step/chain at a time Skip nodal spread incidence: up to 25% Loco-regional nodal staging with PETCT (not that great): 51% (EUS+CT: 83%) Specificity: 84% For F Lower-esophageal esophageal cancer (GE Junction) Lower peri-esophageal Pulmonary ligament Diaphragmatic Retrocrural Rt l Pericardial L-gastric/Gastrohepatic (=resectable, important to DDX from celiac) (Celiac is irresectable=m1a) (M1a if T@lower thoracic & M1b if T@Mid thorax) Cervical node: (M1a of T@upper thorax & M1b if T@ Mid-thorax) 408
: Esophageal Cancer: Resection 5YS: 37% : Esophageal Cancer: T-staging: Depends on Nuclear Grade Size Local extension Tis: In situ T1: Confined to Mucosa/Submucosa T2: Confined to Muscularis Propria T3: Adventitia Invasion T4: Nearby organ invasion Endoscopic US > CT > PET Resection + Chemo Resection + Chemo + RTx 17% 3% N0: No regional node N1: Regional node All other Ns are actually M1! Endoscopic US > CT > PET Palliative: Resection Chemo RTx Once is T4 or M1a/b M1a: Endoscopic US < CT < PETCT Liver(35%) Lung(20%) Bone (9%) Peritoneal (2%) MRI : Esophageal Cancer: M M1a: Non Liver(35%) ( ) Lung(20%) Bone (9%) Peritoneal (2%) : Esophageal Cancer: This is the main utility of PET-CT in Esophageal cancer imaging PETCT CT-alone 67% 37-67% Specificity: 97% Change in management: 5-8% of cases (Mayers et al-2007) : Esophageal Cancer: : Esophageal Cancer: Synchronous malignancy incidence: 1-5% DNA defect Exposed environmental factors Common co-incidental cancers: Multifocal Esophagus (Adeno) (Barrett's) Esophagus (Squamous) + H&N cancers (Smokers) Esophagus (Adeno) + Colon Esophagus (Squamous) + Lung (Squamous) Checklist: Lung Thyroid Colon Breast Uterus Parotid Pancreas Renal Bladder Skin Lymphoma Result: Nodal involvement: CT PETCT 11% < 30% Specificity: 95% > 90% Accuracy: 83% = 82% FP: 28 nodes 56 nodes Mediastinal 11 23 Hilar 4 32 Abdominal 13 1 Conclusion: In Esophageal Squamous cancer Nodal met : PETCT > CT Specificity: PETCT < CT!!!! high FP of PET for hilar nodes PET overcalls hilar node involvement. 409
: Esophageal Cancer: 11C-Choline PET better sensitivity than FDG and CT for mediastinal node assessment. 11C-Cholice Cholice PET: marked hepatic activity: not useful for upper abdominal nodal assessment : Esophageal Cancer: PET improves the accuracy of RT Planning CT shows the radial extension of tumor Radiation Planning PET: More accurate nodal assessment (except those nearby primary lesion) More accurate assessment of longitudinal extension of tumor If endoscopy is limited due to stricture: PET can assess the distal extent accurately Marked impact on GTV & PTV 56% planning change by PETCT! : Esophageal Cancer: Fact: 50-60% failure of response to Neoadjuvent CTx Great need for a tool for early response assessment! : Esophageal Cancer: 1. PETCT is not particularly reliable modality to assess response to therapy in the primary lesion Not tf for Treassessment! 2. If done during therapy: New foci may be found: Up-stage the cancer 8-17% new met can develop during the course of therapy! Many y of them are occult to conventional imaging gmodalities. Able to re-assess for N and M OK for N-& M-reassessment 3. Post neoadjuvent /RT: fat planes become blurry Limited value of CT in accurate assessment PETCT may be more useful than CECT alone : Esophageal Cancer: 1. PETCT is not particularly reliable modality to assess response to therapy in the primary lesion Not N tfor Treassessment! Used U d criteria i (controversial): Residual SUVmax > 4: SUVmax drop > 35-60% Poor survival Better px : Esophageal Cancer: Best time to image (Controversial): CTx/RTx can induce inflammation: usually causing increase in FDG avidity. Time of onset of Post-Tx esophagitis: 14-35 day So best time would be before onset of esophagitis, limiting FP results Within 2 weeks of initiation of therapy Upon completion of therapy (CTx/RTx) repeat scan can provide insight for prognosis: Hi-residual activity: Non-responder: Poor prognosis Best time for scanning: Post RTX: 2 months Post P tctx: 1 month 410
: Esophageal Cancer: : Esophageal Cancer: Data: Brucher et al: (n=27) Those with 52% SUV drop in post-tx: 1- Differentiate Responders from Non-responders 100% Specificity: 55% 2- Shorter 5 year survival Flamen et al: (n=36) 3-4 weeks post-tx 80% drop Tumor/Liver ratio: Differentiate Responders from Non-responders 71% Specificity: 82% For response to therapy: Sensitivity Specificity CT: 33-55% 50-71% EUS: 50-100% 36-100% PETCT: 71-100% 100% 55-100% Downey et al: (n=17) Post-CTx 60% drop in max SUV: 2 year survival: 67% vs 38% Swisher et al: (n=103) Post-CTx max SUV threshold of 4: 18 month survival: maxsuv > 4: 34% maxsuv<4: 77% 67 YM Esophageal cancer Initial PETCT: Avid GEJ esophageal ca (SUV: 9) +No met seen 3 mon post CTx: Rd Reduction of fsuvt to 5.6 56 +No met seen Dx: Good response to therapy. Favorable prognosis. : Esophageal Cancer: Re-staging (R/O: Recurrence) Comparable results between PETCT versus CT (w/wo EUS) Data: PETCT CECT Sensitivity y for recurrence detection: 87-100% = 81-100% Specificity: 57-95% < 84-98% Part of problem: peri-anastomosis area: hot on PETfor longtime: cause of overcall on PET (FP): leading to lower specificity in comparison to CT Thank you for your attention. Bijan Questions & Comments 411