[PET-CT with intravenous contrast in the evaluation of patients with lymphoma. Contribution to diagnostic indications].
OBJECTIVE
To define the utility of intravenous contrast administration in the PET-CT (PET-CTc) in patients with lymphoma in order to determine its possible indications.


METHODS
78 patients with lymphoma were prospectively evaluated. All underwent simultaneous PET-CTc scans in a hybrid system for staging (8), evaluation of response to treatment (29), suspicion of recurrence (9) and complete remission control (48). The PET scan was acquired by a conventional method and the diagnostic CT scan was performed according to radiological protocol. Both examinations were evaluated blinded and independently, analyzing 28 anatomical locations in order to determine the degree of agreement. Final diagnosis was established by the clinician based on the histological study, results of other diagnostic techniques or clinical follow-up.


RESULTS
The final result of both techniques were concordant in 87/94 studies (92.5%). A total of 158 (36 FP) pathological locations were detected with PET-CT and 189 (71 FP) with CTc, with 72 locations being discordant between both techniques. Global sensitivity, specificity, PPV and NPV were 93%, 98%, 77% and 99%; and 94%, 97%, 62% and 99%, respectively.


CONCLUSIONS
Administration of intravenous contrast does not seem to provide any advantage in the determination of nodal and extranodal disease in lymphoma patients. The low prevalence of disease probably accounts for the limited PPV of both techniques. An increase of our sample size, with a greater homogeneity of the groups, should offer more reliable results.
Talavera Rubio
M P
MP
Servicio de Medicina Nuclear, Hospital General Ciudad Real, Ciudad Real, España. mdtalavera@sescam.jccm.es
García Vicente
A M
AM
Domínguez Ferreras
E
E
Calle Primo
C
C
Poblete García
V M
VM
Hernández Ruiz
B
B
Bellón Guardia
M
M
Palomar Muñoz
A
A
Cepedello Boiso
I
I
Pilkington Woll
P
P
González García
B
B
Cordero García
J M
JM
Molino Trinidad
C
C
Soriano Castrejón
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008223:Lymphoma / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult
D003287:Contrast Media