Dynamic contrast-enhanced MRI coupled with a subtraction technique is useful for treatment response evaluation of malignant melanoma hepatic metastasis

PURPOSE

To determine whether contrast-enhanced MRI including subtraction sequences can predict the treatment response of melanoma liver metastasis.

RESULTS

High precontrast T1 signal intensity (SI) of melanoma lesions obscured detection of enhancement after contrast injection. It was impossible to determine whether or not enhancement occurred in the majority of lesions (85.4%, n = 35/41) without including the subtraction technique. Positive enhancement was identified in 14.6% (n = 6/41) of patients without subtraction images, but increased to 68.3% (n = 28/41) by including subtraction images. Follow-up studies determined lesion progression in 34.1% (n = 14/41) of patients. Positive enhancement on the subtraction image (odds ratio = 12.1, P = 0.048) and intermediate high T2 SI (odds ratio = 8.16, P = 0.040) were significantly associated with higher risk of lesion progression.

MATERIALS AND METHODS

Patients who underwent MRI for melanoma liver metastases between January 2007 and February 2015 were enrolled. The study analyzed 41 liver metastases in 15 patients [11 male and four female; median age 56 years (range 21-81)] for size, lesion enhancement with and without subtraction images, and T2 SI. Follow-up imaging studies were used to determine treatment response. Data were analyzed with generalized estimating equations.

CONCLUSIONS

MRI including the subtraction technique is useful for determining the treatment response of melanoma liver metastases. Lesion contrast enhancement and intermediate high T2 SI increased the risk of lesion progression.

Liver resection and ablation for metastatic melanoma: A single center experience

BACKGROUND

The median survival for patients with stage IV metastatic melanoma is usually limited to approximately 1 year. In the case of liver metastasis, resection and ablation can achieve long-term survival. This study aimed to describe the outcomes after liver resection or ablation for metastatic melanoma to the liver and identify preoperative prognostic factors.

METHODS

Forty eight patients who underwent liver resection (n = 32) or percutaneous ablation (n = 16) were identified from the 1,523 patients with melanoma liver metastases evaluated between January1993 and January 2013.

RESULTS

Median OS was 25.9 months. Median OS was not different after ablation (18 months) and resection (26 months; P > 0.2). Patients in the ablation group more often presented with extrahepatic disease (EHD) (P = 0.008) and received more frequently systemic therapy before ablation (P = 0.005). Patients without EHD tended to have longer OS (26.5 vs. 12 months; P = 0.076) and PFS (13 vs. 5 months; P = 0.11) in the whole cohort. EHD was significantly associated with a worse OS in the resection group (P = 0.034).

CONCLUSION

Liver resection is associated to prolonged survival over 24 months and should be considered only in selected patients with metastatic disease confined to the liver. In patients not candidate for surgery, tumor ablation can be considered.