Trial Information

Whole Body Diffusion MRI for Non-invasive Lesion Detection and Therapy Follow-up: Study With Patients With Ovarian Cancer and Peritoneal Metastasis

BACKGROUND OF THE STUDY

Ovarian cancer is a gynecological cancer with a high risk of mortality. This is because the
diagnosis is often been made in an advanced cancer stage with metastases throughout the
peritoneum. The standard treatment for this condition till now consisted of primary
debulking surgery where the tumor, the uterus and both the ovaries were removed, followed by
a minimum of six treatments with platinum-based chemotherapy. This operation is often
accompanied by serious complications such as for example bleedings, embolic events,
infections and in extreme cases, even mortality. An international study led by Prof. Dr.
Ignace Vergote (Gynaecological Oncology) showed for the first time that patients in such an
advanced stage of ovarian cancer who received first three neoadjuvant platinum-based
chemotherapy regimens followed by interval debulking surgery, and in turn followed by at
least 3 treatment with platinum-based chemotherapy, had fewer complications than patients
treated with primary debulking surgery followed by chemotherapy. Moreover, the final
survival rate in both groups seemed to be similar. The most important prognostic marker
appeared to be whether patients with primary or interval surgery no longer had a visible
residual tumor after the treatment. Patients who had only small metastases in the
peritoneum, seemed to be better treated with primary surgery (neoadjuvant Vergote I, et al
Chemotherapy or Primary Surgery in Stage IIIC or IV Ovarian Crystallising, N Engl J Med 363
(1910): 943 - 953).

Each patient with suspected advanced ovarian cancer should undergo a preoperative evaluation
where they assess which of the two treatments is the best option. This should of course, for
each individual patient, take into account comorbidity, cancer stage, number and location of
the metastases etc. Currently,[18F] FDG-PET/CT, CT and conventional MRI are being used for
staging, detecting recurrence and metastasis and for evaluating therapy response. These
techniques have some disadvantages. A PET study takes a long time to perform and makes use
of radioactive material. The addition of CT also gives rise to additional radiation. [18F]
FDG accumulates in inflammatory cells in the tumor. This can explain the difficulties
concerning early evaluation of treatment response. Although CT allows high resolution images
of the entire body, sometimes the technology lacks sufficient sensitivity or specificity.
Although conventional MRI has the highest sensitivity for detection of liver metastases, the
lack of efficient whole-body imaging for staging a disadvantage when assessing systemic
tumor spread and metastasis. Small peritoneal metastases are therefore often missed with
this technique.

Diffusion-weighted imaging (DWI) is an emerging technology that is currently being uses in
cancer imaging. Here the difference in movement of water molecules provides information
about the integrity of cellular membranes. DWI has the advantage that no contrast material
is required and there is also no need for exposure to ionizing radiation. Further
developments in technology allowed for an acceptable time in whole body conducting research,
so we should be able to image gastrointestinal tumors with this whole body technique.

AIM OF THE STUDY

The aim of the study is to assess whole body diffusion weighted imaging (WB-DWI) as a
non-invasive method, in patients with confirmed ovarian cancer in the presence of peritoneal
metastases. This is to assess which of the two treatments (primary debulking surgery
followed chemotherapy versus platinum-based neoadjuvant chemotherapy followed by interval
debulking surgery, followed in turn by chemotherapy) is the best option for a particular
type of patient.