Ultrasound as a tool to evaluate remission of cutaneous Kaposiʼs sarcoma

Abstract

To evaluate ultrasound measurement of Kaposi's sarcoma (KS) tumour volume for follow-up during therapy. Two-dimensional evaluation of size and description of gross alteration (for example, colour, nodularity, resolution) was used to assess treatment of KS. Flattening of palpable cutaneous KS lesions during anti-KS therapy has not been quantified objectively by a reliable method. In six patients with advanced AIDS and KS, a total of 17 cutaneous lesions were evaluated prospectively by ultrasound and surface measurements. KS lesions were examined histologically before and after 12 weeks of chemotherapy with liposomal doxorubicin. In comparison with size reduction, volume measurement showed a more pronounced reduction of tumour volume. The mean tumour volume was reduced by 94% from 451 mm3 +/- 655 mm3 to 66 mm3 +/- 165 mm3 at week 12 (P < 0.001). Histological evaluation of lesions no longer detectable by ultrasound after therapy showed abundant siderophages but no increase in spindle cells and no mitoses. Our findings suggest that ultrasound is a useful method with which to follow growth and remission of cutaneous KS. In contrast, pigmentation due to iron deposition is unaffected by chemotherapy because, despite histological remission, pigmentation can persist. Though ultrasound cannot replace histologic evaluation for complete response, we suggest the use of ultrasound assessment, thus introducing a more objective criterion than subjective rating of nodularity.