Isolated nodular metastases in perirenal space: our experience of nine cases and review of the literature.

AIM: The aim of this paper was to report authors' experience and review of the literature on rare isolated perirenal space metastases from different primary tumors.

METHODS

From January 2004 to August 2008 we evaluated retrospectively 9 patients with isolated nodular neoplastic lesions of the perirenal space with computed tomography (CT) imaging and we reported the follow-up after relapse of disease.

RESULTS

All the masses resulted being of secondary tumor involvement (melanoma (2/9 cases 22.22%), esophagus-gastric tract adenocarcinoma (3/9 cases 33.33%), gynecological tumor (2/9 cases 22.22%) and gastrointestinal tumor (2/9 cases, 22.22%), diagnosed by biopsy CT-guided (2 cases), or histological post-surgical examination (1 case), or clinical and instrumental follow-up (4 cases) or postmortem examination (2 cases). The lesions were bilateral in 3 cases and monolateral in 6 cases, isolated in four cases and multiple in five cases; they have demonstrated partially necrotic parenchymal density as soft tissues masses, with frequently hypervascularization, with portal venous enhancement. The dimensions of lesions resulted to be between minimal value of about 7-8 mm and maximum value of about 50 mm (mean 29 mm). The patients had generally poor prognosis (death for disease ‑ DOD ‑ in 5 cases; life with disease - LWD ‑ in four cases).

CONCLUSION

Isolated perirenal metastases are unusual site of relapse of disease. Our study confirms the utility of CT evaluation of metastatic localization of perirenal space; this technique can also be used for focused biopsies and follow-up. This site of isolated metastases had a poor prognosis.