Clinical Trial: Ga-68-DOTATOC -PET in the Management of Pituitary Tumours

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: Ga-68-DOTATOC -PET in the Management of Pituitary Tumours

Brief Summary:

Title: Gallium (GA) -68-DOTATOC -PET (positron emission tomography) in the management of pituitary tumours Medical product: Ga-68-DOTATOC in PET/computer tomography (CT) Route of administration: Intravenously Diseases of interest: Pituitary tumours Aim: To study the detection of pituitary tumours with Ga-68-DOTATOC -PET (Ga-PET) and to correlate the tracer expression to somatostatin receptor (sst) occurrence Study design: Prospective non-randomised case-control study with open design with GA-PET before and after pituitary surgery in patients with pituitary tumours Study population: patients with acromegaly (n=10), Cushing's' disease of pituitary origin (n=10), TSH (thyreotropin) producing tumours (TSHomas) (n=5) and non-functioning pituitary adenomas (NFPA) (n=20) Number of patients: 45 Inclusion criteria: Adult man or woman (over 18 years) and naïve, unoperated pituitary tumour with growth hormone (GH) or adrenocorticotrophic hormone (ACTH)) or TSH production or NFPA without treatment with somatostatin analogues (SSA) or dopamine agonists.

Exclusion criteria: Patient who may not attend to the protocol according to the investigators opinion. Pregnancy or lactating. Isolated prolactin producing tumours. Overproduction of gonadotropins. Carcinoids ie ectopic corticotrophin realising factor (CRF) production. Known or suspected allergy to the trial product or related products.

Controls: Adult patients with Thyroid associated ophthalmopathy (TAO) before iv steroid infusion (part of another study see this protocol)- Study variables: Tumour detection, Tracer uptake as Standardised uptake value (SUV) max (SUVmax), SUV hotspot and SUV mean in regions of interests (ROIs) Time schedule: Recruitment of patients 2015-2017. Study termination 3 years later


Detailed Summary:

Background The most common cause to pituitary insufficiency is the pituitary adenoma (PA). PA may be divided into hormone producing PAs and non-functioning PAs (NFPA). Normal pituitary tissue, as well as tissues from PAs, expresses somatostatin receptors (sst). Five subtypes of sst receptors has been characterized.

Magnetic resonance tomography (MRI) presents anatomy, while in vivo diagnostics with somatostatin receptor scintigraphy (SRS) or position emission tomography (PET) reflect the functional properties of the tissue. The SRS have earlier been evaluated for diagnostics of pituitary diseases and has low discriminative ability to differ tumor tissue from normal pituitary tissue even though some secretory tumors and NFPA are seen. The superiority of the PET in diagnostics compared to the SRS is based on higher spatial resolution and a higher tumor to background ratio. Therefore it is of large interest to study Gallium 68 DOTATOC (Ga-PET) i small tumours that exhibit sst, such as in the pituitary, where high resolution is essential to discriminate from normal tissue and to evaluated residual tumor tissue postoperatively.

Aim with the project

To evaluate Ga-PET in the management of pituitary tumors and to seek the answer to the following questions:

  1. Is the method of value in primary diagnostics in PAs? Does Ga-PET contribute with more functional information than that given from an conventional MRI?
  2. Is the method of value in the follow-up, the detection of residual tumor tissue, and increase the possibility to differ scar tissue from true tumor?
  3. Can relapses of PA be detected earlier with Ga-PET than with conventional MRI? Sponsor: Göteborg University

    Current Primary Outcome:

    • SUV max in GA-68 DOTATOC in pituitary tumours in comparison to normal pituitary [ Time Frame: Baseline ]
      Maximum Standardized Uptake Value
    • SUV max in GA-68 DOTATOC in pituitary tumours in comparison to normal pituitary [ Time Frame: measured at 6 months +/- 2 weeks from baseline ]
      Maximum Standardized Uptake Value
    • SUV max in GA-68 DOTATOC in pituitary tumours in comparison to normal pituitary [ Time Frame: measured at 36 months +/- 2 weeks from baseline ]
      Maximum Standardized Uptake Value


    Original Primary Outcome: Same as current

    Current Secondary Outcome:

    • Ga-PET uptake in correlation to sst expression in pituitary tumours, measured as SUVmax which is then used to establish statistical relationship with a cell membrane-based sst-immunohistochemistry (IHC) score" [ Time Frame: Baseline ]
    • Ga-PET uptake in correlation to sst expression in pituitary tumours, measured as SUVmax which is then used to establish statistical relationship with a cell membrane-based sst-immunohistochemistry (IHC) score" [ Time Frame: measured at 6 months +/- 2 weeks from baseline ]
    • Ga-PET uptake in correlation to sst expression in pituitary tumours, measured as SUVmax which is then used to establish statistical relationship with a cell membrane-based sst-immunohistochemistry (IHC) score" [ Time Frame: measured at 36 months +/- 2 weeks from baseline ]
    • Adverse event registration in association to Ga-68 PET [ Time Frame: Baseline ]
    • Adverse event registration in association to Ga-68 PET [ Time Frame: measured at 6 months +/- 2 weeks from baseline ]
    • Adverse event registration in association to Ga-68 PET [ Time Frame: measured at 36 months +/- 2 weeks from baseline ]
    • Detection of tumour recurrence with Ga-PET [ Time Frame: measured at 6 months +/- 2 weeks from baseline ]
    • Detection of tumour recurrence with Ga-PET [ Time Frame: measured at 36 months +/- 2 weeks from baseline ]


    Original Secondary Outcome: Same as current

    Information By: Göteborg University

    Dates:
    Date Received: January 19, 2015
    Date Started: January 2015
    Date Completion: December 2019
    Last Updated: February 1, 2017
    Last Verified: February 2017