Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemotherapy: The Implications of Metabolic Nodal Response for Personalized Therapy.

Authors: Findlay, J.M., Bradley, K.M., Wang, L.M., Franklin, J.M., Teoh, E.J., Gleeson, F.V., Maynard, N.D., Gillies, R.S. and Middleton, M.R.

Journal: J Nucl Med

Volume: 58

Issue: 2

Pages: 266-275

eISSN: 1535-5667

DOI: 10.2967/jnumed.116.176313

Abstract:

UNLABELLED: Only a minority of esophageal cancers demonstrates a pathologic tumor response (pTR) to neoadjuvant chemotherapy (NAC). 18F-FDG PET/CT is often used for restaging after NAC and to assess response. Increasingly, it is used during therapy to identify unresponsive tumors and predict pTR, using avidity of the primary tumor alone. However, definitions of such metabolic tumor response (mTR) vary. We aimed to comprehensively reevaluate metabolic response assessment using accepted parameters, as well as novel concepts of metabolic nodal stage (mN) and metabolic nodal response (mNR). METHODS: This was a single-center retrospective U.K. cohort study. All patients with esophageal cancer staged before NAC with PET/CT and after with CT or PET/CT and undergoing resection from 2006 to 2014 were identified. pTR was defined as Mandard tumor regression grade 1-3; imaging parameters included metrics of tumor avidity (SUVmax/mean/peak), composites of avidity and volume (including metabolic tumor volume), nodal SUVmax, and our new concepts of mN stage and mNR. RESULTS: Eighty-two (27.2%) of 301 patients demonstrated pTR. No pre-NAC PET parameters predicted pTR. In 220 patients restaged by PET/CT, the optimal tumor ΔSUVmax threshold was a 77.8% reduction. This was as sensitive as the current PERCIST 30% reduction, but more specific with a higher negative predictive value (P < 0.001). ΔSUVmax and Δlength independently predicted pTR, and composite avidity/spatial metrics outperformed avidity alone. Although both mTR and mNR were associated with pTR, in 82 patients with 18F-FDG-avid nodes before NAC we observed mNR in 10 (12.2%) not demonstrating mTR. CONCLUSION: Current definitions of metabolic response are suboptimal and too simplistic. Composite avidity/volume measures improve prediction. mNR may further improve response assessment, by specifically assessing metastatic tumor subpopulations, likely responsible for disease relapse, and should be urgently assessed when considering aborting therapy on the basis of mTR alone.

https://eprints.bournemouth.ac.uk/34605/

Source: PubMed

Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemotherapy: The Implications of Metabolic Nodal Response for Personalized Therapy

Authors: Findlay, J.M., Bradley, K.M., Wang, L.M., Franklin, J.M., Teoh, E.J., Gleeson, F.V., Maynard, N.D., Gillies, R.S. and Middleton, M.R.

Journal: JOURNAL OF NUCLEAR MEDICINE

Volume: 58

Issue: 2

Pages: 266-275

eISSN: 1535-5667

ISSN: 0161-5505

DOI: 10.2967/jnumed.116.176313

https://eprints.bournemouth.ac.uk/34605/

Source: Web of Science (Lite)

Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemotherapy: The Implications of Metabolic Nodal Response for Personalized Therapy

Authors: Findlay, J.M., Bradley, K.M., Wang, L.M., Franklin, J., Teoh, E.J. and Gleeson, F.V.

Journal: Journal of Nuclear Medicine

Volume: 58

Issue: 2

Pages: 266-275

Publisher: Science Press

ISSN: 0161-5505

DOI: 10.2967/jnumed.116.176313

https://eprints.bournemouth.ac.uk/34605/

Source: Manual

Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemotherapy: The Implications of Metabolic Nodal Response for Personalized Therapy.

Authors: Findlay, J.M., Bradley, K.M., Wang, L.M., Franklin, J.M., Teoh, E.J., Gleeson, F.V., Maynard, N.D., Gillies, R.S. and Middleton, M.R.

Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine

Volume: 58

Issue: 2

Pages: 266-275

eISSN: 1535-5667

ISSN: 0161-5505

DOI: 10.2967/jnumed.116.176313

Abstract:

Only a minority of esophageal cancers demonstrates a pathologic tumor response (pTR) to neoadjuvant chemotherapy (NAC). 18F-FDG PET/CT is often used for restaging after NAC and to assess response. Increasingly, it is used during therapy to identify unresponsive tumors and predict pTR, using avidity of the primary tumor alone. However, definitions of such metabolic tumor response (mTR) vary. We aimed to comprehensively reevaluate metabolic response assessment using accepted parameters, as well as novel concepts of metabolic nodal stage (mN) and metabolic nodal response (mNR).

Methods

This was a single-center retrospective U.K. cohort study. All patients with esophageal cancer staged before NAC with PET/CT and after with CT or PET/CT and undergoing resection from 2006 to 2014 were identified. pTR was defined as Mandard tumor regression grade 1-3; imaging parameters included metrics of tumor avidity (SUVmax/mean/peak), composites of avidity and volume (including metabolic tumor volume), nodal SUVmax, and our new concepts of mN stage and mNR.

Results

Eighty-two (27.2%) of 301 patients demonstrated pTR. No pre-NAC PET parameters predicted pTR. In 220 patients restaged by PET/CT, the optimal tumor ΔSUVmax threshold was a 77.8% reduction. This was as sensitive as the current PERCIST 30% reduction, but more specific with a higher negative predictive value (P < 0.001). ΔSUVmax and Δlength independently predicted pTR, and composite avidity/spatial metrics outperformed avidity alone. Although both mTR and mNR were associated with pTR, in 82 patients with 18F-FDG-avid nodes before NAC we observed mNR in 10 (12.2%) not demonstrating mTR.

Conclusion

Current definitions of metabolic response are suboptimal and too simplistic. Composite avidity/volume measures improve prediction. mNR may further improve response assessment, by specifically assessing metastatic tumor subpopulations, likely responsible for disease relapse, and should be urgently assessed when considering aborting therapy on the basis of mTR alone.

https://eprints.bournemouth.ac.uk/34605/

Source: Europe PubMed Central

Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemotherapy: The Implications of Metabolic Nodal Response for Personalized Therapy

Authors: Findlay, J.M., Bradley, K.M., Wang, L.M., Franklin, J.M., Teoh, E.J. and Gleeson, F.V.

Journal: Journal of Nuclear Medicine

Volume: 58

Issue: 2

Pages: 266-275

ISSN: 0161-5505

https://eprints.bournemouth.ac.uk/34605/

Source: BURO EPrints