Pseudomyxoma peritonei: role of 18F-FDG PET in preoperative evaluation of pathological grade and potential for complete cytoreduction.
BACKGROUND
For pseudomyxoma peritonei (PMP), survival depends on pathological grade and completeness of cytoreductive surgery. The aim of the study was to assess the ability of preoperative 18F-FDG PET to determine these 2 prognosis indicators.


METHODS
In this prospective single centre study, all patients presenting with PMP were included. They underwent a preoperative 18F-FDG PET with a double radiological evaluation and an explorative laparotomy with the objective of optimal cytoreduction followed by a hyperthermic intra-operative intraperitoneal chemotherapy (HIPEC). Patients with non resectable disease underwent debulking surgery without HIPEC. The Completeness of Cytoreduction was assessed by CC score.


RESULTS
Thirty-four patients were included. PET scanning was positive for 19 patients with grade II (hybrid form) or III (Peritoneal Mucinous Carcinomatosis) and for 2 patients with grade I (disseminated peritoneal adenomucinosis), and negative for 3 patients with grade II - III and for 10 patients with grade I. PET scanning was positive for 6 patients with CC score 2 - 3 and for 16 patients with CC score 0, and negative for 2 patients with CC score 2 - 3 and for 10 patients with CC score 0. The 18F-FDG PET interpretation distinguished 2 patients groups (grade I and grade II - III) with a sensitivity of 90% and a specificity of 77%. Moreover, probability of complete cytoreduction when PET was negative was over 80%.


CONCLUSIONS
Preoperative 18F-FDG PET may predict pathological grade and completeness of cytoreduction which are the two main prognostic factors in patients with PMP.
Passot
G
G
Department of oncologic surgery, Centre Hospitalier Lyon Sud, Pierre Bénite, France.
Glehen
O
O
Pellet
O
O
Isaac
S
S
Tychyj
C
C
Mohamed
F
F
Giammarile
F
F
Gilly
F N
FN
Cotte
E
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D007813:Laparotomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010534:Peritoneal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D049268:Positron-Emission Tomography / Q000379:methods*; D011300:Preoperative Care / Q000379:methods*; D011379:Prognosis; D011446:Prospective Studies; D011553:Pseudomyxoma Peritonei / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D019275:Radiopharmaceuticals
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18