DOI: 10.1007/s00259-017-3856-4Pages: 1-10

Immunohistochemical evaluation of molecular radiotherapy target expression in neuroblastoma tissue

1. University College London Hospitals NHS Foundation Trust, Department of Oncology

2. Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Pathology

3. University of Birmingham, Cancer Research UK Clinical Trials Unit

Correspondence to:
Mark N. Gaze
Tel: 020 3447 9088
Email: mgaze@nhs.net

Close

Abstract

Purpose

Neuroblastoma may be treated with molecular radiotherapy, 131I meta-Iodobenzylguanidine and 177Lu Lutetium DOTATATE, directed at distinct molecular targets: Noradrenaline Transporter Molecule (NAT) and Somatostatin Receptor (SSTR2), respectively. This study used immunohistochemistry to evaluate target expression in archival neuroblastoma tissue, to determine whether it might facilitate clinical use of molecular radiotherapy.

Methods

Tissue bank samples of formalin fixed paraffin embedded neuroblastoma tissue from patients for whom clinical outcome data were available were sectioned and stained with haematoxylin and eosin, and monoclonal antibodies directed against NAT and SSTR2. Sections were examined blinded to clinical information and scored for the percentage and intensity of tumour cells stained. These data were analysed in conjunction with clinical data.

Results

Tissue from 75 patients was examined. Target expression scores varied widely between patients: NAT median 45%, inter-quartile range 25% - 65%; and SSTR2 median 55%, interquartile range 30% – 80%; and in some cases heterogeneity of expression between different parts of a tumour was observed. A weak positive correlation was observed between the expression scores of the different targets: correlation coefficient = 0.23, p = 0.05. MYCN amplified tumours had lower SSTR2 scores: mean difference 23% confidence interval 8% - 39%, p < 0.01. Survival did not differ by scores.

Conclusions

As expression of both targets is variable and heterogeneous, imaging assessment of both may yield more clinical information than either alone. The clinical value of immunohistochemical assessment of target expression requires prospective evaluation. Variable target expression within a patient may contribute to treatment failure.

To access the full text, please Sign in

If you have institutional access, please click here

  • Accepted: Oct 9, 2017
  • Online: Oct 17, 2017

Article Tools

eanm
EJNMMI Ad