ULTRASOUND DIAGNOSIS OF SPLENIC LYMPHOMA - ROC ANALYSIS OF MULTIDIMENSIONAL SPLENIC INDEXES

To assess the efficacy of splenic size in the sonographic diagnosis of lymphomatous involvement of the spleen, the authors studied 31 patien ts with splenic lymphoma (Hodgkin's disease, 17 and non-Hodgkin's lymp homa, 14) and 218 individuals without evidence of splenic disease. All subjects were studied with both a linear and a sector transducer. The longitudinal, transverse and diagonal diameters of the spleen were me asured, and two- and three-dimensional splenic indices were calculated . The analysis of the diagnostic performance of these criteria, compar ed by means of receiver-operating characteristic (ROC) curves, reveale d that diagnosis of splenic involvement by malignant lymphoma was cons iderably more reliable with a sector than with a linear scanner. If th e longitudinal diameter was measured with a sector scanner, sensitivit ies were 66% and 74%, at specificities of 95% and 90% respectively (cu t-off points: 12.5 cm and 11.3 cm, respectively). For the sector scann er, there was no advantage in using other diameters or multidimensiona l indices. Additional ROC analysis of recently published data indicati ng excellent discrimination capacity of a computed tomography index re vealed that these results were largely owing to patient selection. In contrast, our data suggest that the potential of current non-invasive assessment of splenic lymphoma is limited. However, ultrasound may eve ntually help to eliminate staging laparotomy in selected cases, e.g. i n patients with low risk of abdominal disease and with increased surgi cal risk.