Common and uncommon histologic subtypes of renal cell carcinoma: imaging spectrum with pathologic correlation

Coexistence of Different Histotypes of Renal Carcinoma: Our Experience and Literature Review

The coexistence of multiple, synchronous primary tumors of different histology within the same kidney is a rare condition. We report herein a series of five patients with two tumors of different histology involving synchronously the same kidney.

Materials and Methods

We reviewed the pathology reports of a series of 381 patients who underwent surgery for primary renal tumors at our institution from 2000 to 2007. In the files of all patients with synchronous tumors of different histology, special attention was given to the results of imaging studies.

Results

Five out of 381 patients (1.37%) had coexistence of two primary tumors of different histology within the same kidney. Four patients had ultrasonography as the first imaging procedure, one patient had ultrasonography as the second imaging procedure; all had preoperative CT of the abdomen. Both lesions were detected by preoperative CT in 4/5 of the cases; in the remaining one, the smaller lesion was not visible, even in retrospect.

Conclusions

The coexistence of multiple and synchronous primary tumors of different histology within the same kidney has been only rarely described. To the best of our knowledge, in literature there are only case reports with the exception of a case of renal oncocytoma with evolving papillary RCC. We believe that this condition could be more frequent if the radiologist and the anatomopathologist try to find it.

Neoplastic and non-neoplastic proliferative disorders of the perirenal space: cross-sectional imaging findings

The perirenal space, located between the anterior and the posterior renal fasciae, is shaped like an inverted cone with an apex that extends into the iliac fossa. Perirenal tumors and pseudotumors primarily originate either from the kidney or as part of a systemic disease process and have characteristic histopathologic features and biologic behavior. The lesions may be classified on the basis of their distribution and imaging features as solitary soft-tissue masses (renal cell carcinoma, lymphangioma, hemangioma, and leiomyoma), rindlike soft-tissue lesions (lymphoma, retroperitoneal fibrosis, and Erdheim-Chester disease), masses containing macroscopic fat (angiomyolipoma, liposarcoma, myelolipoma, and extramedullary hematopoiesis), and multifocal soft-tissue masses (metastases, plasma cell tumors). Because of overlap in imaging findings among these diverse perirenal lesions, a definitive diagnosis in most cases can be established only at histopathologic analysis. However, an imaging pattern-based approach may facilitate the diagnosis and optimal management of perirenal tumors and pseudotumors.

Achados da tomografia computadorizada em metástases pancreáticas do carcinoma de células renais

OBJETIVO: Apresentar os achados da tomografia computadorizada observados em quatro pacientes submetidos a nefrectomia radical por carcinoma de células renais e que apresentaram metástases pancreáticas. MATERIAIS E MÉTODOS: Os quatro pacientes foram submetidos a nefrectomia radical por carcinoma de células renais, estádios T1 (n=2) e T3a (n=2). O intervalo médio entre a nefrectomia e a detecção das metástases foi de oito anos. Dois pacientes apresentaram metástase pancreática solitária (confinada ao pâncreas) e dois apresentaram metástases pancreáticas única e múltiplas, respectivamente, ambos com recorrência tumoral no rim contralateral. RESULTADOS: As metástases pancreáticas foram visualizadas, na tomografia computadorizada, como lesões hipervascularizadas, solitária (n=2), única (n=1) ou múltiplas (n=1). Foi realizada pancreatectomia parcial em dois pacientes com metástase solitária. Estes pacientes estão livres da doença quatro e dois anos após a cirurgia, respectivamente. CONCLUSÃO: Metástases pancreáticas de carcinoma de células renais são raras, podendo ocorrer muitos anos após a apresentação inicial. Metástases pancreáticas múltiplas e metástases pancreáticas associadas a recorrência tumoral no rim contralateral são incomuns. À tomografia computadorizada, as metástases pancreáticas aparecem como lesões hipervascularizadas e solitárias, simulando tumores das ilhotas celulares. O tratamento cirúrgico das lesões solitárias deve ser considerado.

Safety and efficacy of CT-guided percutaneous cryoablation for renal cell carcinoma

PURPOSE

Image-guided percutaneous cryoablation is a treatment alternative for selected patients with renal cell carcinoma (RCC). The objective of the present study was to present the safety and efficacy of percutaneous cryoablation.

MATERIALS AND METHODS

The study included 51 lesions in 46 consecutive patients treated with computed tomography (CT)-guided percutaneous cryoablation. Results were based on 40 RCCs with follow-up. Patients had baseline history and physical and laboratory examinations and renal CT or magnetic resonance (MR) imaging and were followed every 3 months. Biopsy of all lesions was performed before or at the time of the procedure. Efficacy was defined as a complete lack of enhancement on follow-up contrast agent-enhanced CT or MR imaging. Lesion size was also followed and correlated with lack of enhancement. Short- and long-term complications were tabulated.

RESULTS

The technical success rate was 100%, with 20% of cases requiring some form of thermal protection of an adjacent organ. During follow-up (median, 28 weeks; range, 4-81 weeks), the efficacy rate was 100% for lesions smaller than 7 cm. The incidence of significant complications was 18% (8% CTAE), mostly (10%) intercostal or genitofemoral nerve injury. All patients with complications recovered fully, and there were no mortalities. There was no change in creatinine levels, and no patient developed renal failure as a result of cryoablation.

CONCLUSIONS

CT-guided percutaneous cryoablation resulted in complete response for lesions as large as 4 cm. It may also be a viable alternative for nonsurgical candidates with lesions as large as 7 cm. It has a high efficacy rate, and its modest complications are not only comparable to those of other treatment modalities, but also appear to be reversible.

Synchronous primary tumors of the kidney and the ovaries: Imaging findings

The simultaneous presence of primary carcinomas in the same patient is uncommon and synchronous primary tumors involving the kidney and ovary are extremely rare. There are a few reports in the English literature of synchronous primary malignancies of the kidney and the ovaries, but no data regarding their imaging features. We present a case of an elderly woman, diagnosed with bilateral ovarian clear cell carcinomas and a simultaneous clear cell carcinoma of the right kidney, evaluated by multidetector CT and MR imaging.