title: Significant impact of transient deterioration of renal function on dosimetry in PRRT.
abstract: Peptide receptor radionuclide therapy (PRRT), with (90)Y-DOTATOC and (177)Lu-DOTATATE as most clinically used radiopeptides, is widely used in the management of metastatic neuroendocrine tumors. With respect to radiation dosimetry, the kidneys are the critical organ for (90)Y-DOTATOC. Renal irradiation is significant because of reabsorption of the radiopeptide from the proximal tubuli and the resulting retention in the interstitium, mainly in the inner cortical zone. The high energy and consequently wide range in tissue of the yttrium-90 beta particle result in high absorbed doses to the kidney cortex and medulla. Accurate renal dosimetry can help minimizing radiation nephropathy. We report a case of a 69-year-old candidate for PRRT with an acceptable kidney function at the time of screening. When performing (111)In-octreotide pretreatment dosimetry 3 weeks later, we observed a drastic deterioration in kidney function, caused by undisclosed non-steroidal anti-inflammatory drug intake. The calculated kidney biological effective dose (BED) was 153 Gy after four projected cycles. PRRT was canceled as our full-course BED limit is 37 Gy and the patient was switched to morphine analgesics. Renal function normalized after 3 months and repeated dosimetry yielded an acceptable kidney BED of 28 Gy after four projected cycles (7 Gy/cycle). This case emphasizes that acute kidney insufficiency can yield toxic kidney doses in a single therapy cycle, with an inherent risk of persistent renal insufficiency. All clinical factors which might influence kidney function should be verified at screening and before PRRT administration.
authors.affiliation: Department of Nuclear Medicine, University Hospitals Leuven, Belgium.
authors.forename: Sofie
authors.initials: S
authors.lastname: Van Binnebeek
authors.forename: Kristof
authors.initials: K
authors.lastname: Baete
authors.forename: Christelle
authors.initials: C
authors.lastname: Terwinghe
authors.forename: Bert
authors.initials: B
authors.lastname: Vanbilloen
authors.forename: Karin
authors.initials: K
authors.lastname: Haustermans
authors.forename: Luc
authors.initials: L
authors.lastname: Mortelmans
authors.forename: Ivan
authors.initials: I
authors.lastname: Borbath
authors.forename: Eric
authors.initials: E
authors.lastname: Van Cutsem
authors.forename: Chris
authors.initials: C
authors.lastname: Verslype
authors.forename: Felix M
authors.initials: FM
authors.lastname: Mottaghy
authors.forename: Alfons
authors.initials: A
authors.lastname: Verbruggen
authors.forename: Christophe M
authors.initials: CM
authors.lastname: Deroose
mesh_terms: D000368:Aged; D006801:Humans; D007414:Intestinal Neoplasms / Q000503:physiopathology / Q000532:radiotherapy; D007668:Kidney / Q000502:physiology* / Q000528:radiation effects*; D008297:Male; D018358:Neuroendocrine Tumors / Q000503:physiopathology / Q000532:radiotherapy; D015282:Octreotide / Q000009:adverse effects / Q000031:analogs & derivatives / Q000378:metabolism / Q000627:therapeutic use; D009942:Organometallic Compounds / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use; D058958:Organs at Risk / Q000528:radiation effects*; D011874:Radiometry; D011878:Radiotherapy / Q000009:adverse effects*; D018000:Receptors, Peptide / Q000378:metabolism*; D013997:Time Factors
chemical_list: D009942:Organometallic Compounds; D018000:Receptors, Peptide; C496730:90Y-octreotide, DOTA-Tyr(3)-; C447941:lutetium Lu 177 dotatate; D015282:Octreotide