Cytoreductive nephrectomy in metastatic renal cell carcinoma

Use of Sorafenib in Two Metastatic Renal Cell Cancer Patients with End-Stage Renal Impairment Undergoing Replacement Hemodialysis

Patients with renal cell carcinoma (RCC) may exhibit renal impairment as a more or less direct consequence of their primary disease. Renal impairment may become a severe complication and alter the normal pharmacokinetic and pharmacodynamic behavior of treatment drugs, thus increasing the risk of side effects. We will discuss the cases of two advanced RCC patients with end-stage renal impairment submitted to dialysis who were treated with sorafenib tosylate in our center.

Our experience confirms the scarce literature data available so far that indicate that sorafenib can be used in patients undergoing dialysis. Dialysis cannot be considered per se a contraindication to sorafenib therapy, which can be effective. However, patients must be carefully selected and monitored, since sorafenib administration unquestionably increases the risk of side effects in patients affected by several conditions.

Potent anticarcinoma activity of the humanized anti-CD70 antibody h1F6 conjugated to the tubulin inhibitor auristatin via an uncleavable linker

PURPOSE

The antitubulin agent monomethyl auristatin F (MMAF) induces potent antitumor effects when conjugated via protease cleavable linkers to antibodies targeting internalizing, tumor-specific cell surface antigens. Humanized 1F6 (h1F6) is a humanized monoclonal antibody targeting CD70, a member of the tumor necrosis factor family that is expressed on hematologic malignancies and carcinomas. Here, we tested h1F6-maleimidocaproyl (mc) MMAF conjugates, consisting of an uncleavable mc linker, for their ability to interfere with the growth of CD70-positive carcinomas.

EXPERIMENTAL DESIGN

To evaluate the optimal drug per antibody ratio, we conjugated either four or eight MMAF molecules to the cysteines that comprise the interchain disulfides of h1F6 and determined antitumor activities in vitro and in xenografted mice. The tumor types tested included glioblastoma, patient-derived renal cell carcinoma (RCC) cell isolates, and standard RCC tumor cell lines.

RESULTS

All h1F6-mcMMAF conjugates potently interfered with the growth of all carcinomas in vitro and resulted in complete responses of RCC tumors implanted orthotopically or s.c. in mice. In vitro, h1F6-mcMMAF(8) was generally more potent than h1F6-mcMMAF(4). However, h1F6-mcMMAF(4) displayed equal or better efficacy than h1F6-mcMMAF(8) when administered to tumor-bearing mice.

CONCLUSIONS

We showed that h1F6-mcMMAF conjugates inhibited the growth of human carcinomas and that increased drug loading, while improving potency in vitro, did not substantially affect the pharmacodynamic and pharmacokinetic properties in vivo. Based on these findings, h1F6-mcMMAF(4), designated SGN-75, has been identified as a potential antibody-drug conjugate for clinical development.

[Neoadjuvant therapy for renal cancer]

A 73-year-old man presented with renal cell carcinoma of the left kidney. Despite the absence of metastases, primary nephrectomy was not performed immediately due to the large tumour volume and the presence of large lymph node extension. The patient was treated with sunitinib for 10 months. Computed tomography at the end of treatment showed a significant reduction of the size of the tumour and the volume of lymph node extension. Radical nephrectomy was then performed. On histological evaluation, the primary renal tumour and, to a lesser degree, the lymph nodes were predominantly necrotic.