Ken-ryu Han

Third‐generation cryosurgery for primary and recurrent prostate cancer

The development of third-generation cryosurgery included two more advances. Gas-driven probes were first described in 1997 by Wong et al. [6], followed shortly by Chin et al. [7]. This system signalled the transition from liquid nitrogen to gas-driven probes in which pressurized gas can be used to both freeze (argon gas) and actively thaw (helium gas) the organ, using the JouleThompson effect, in which different gases undergo unique temperature changes when de-pressurized, according to unique gas coefficients. This transition from liquid to gas permits the use of smaller diameter probes. This report presents a new technique using third-generation cryosurgery probes or ‘cryoneedles’ that allow for direct transperineal probe placement through a brachytherapy-like template, without using tract dilatation and insertion kits. Table 1 summarizes the history and development of cryosurgery for the prostate.

Epithelial Cell Adhesion Molecule (KSA) Expression Pathobiology and Its Role as an Independent Predictor of Survival in Renal Cell Carcinoma

Purpose: Epithelial cell adhesion molecule (EpCAM) is a widely expressed adhesion molecule in epithelial cancers. The purpose of this study is to determine the protein expression patterns of EpCAM in renal cell carcinoma (RCC) using tissue arrays linked to a clinicopathological database to evaluate both its predictive power in patient stratification and its suitability as a potential target for immunotherapeutic treatment strategies. Experimental Design: The University of California, Los Angeles kidney cancer tissue microarray contains specimens from 417 patients treated with nephrectomy. EpCAM protein expression in tumors and matched morphologically normal renal tissues was evaluated using anti-EpCAM immunohistochemistry. The resultant expression reactivity was correlated with clinicopathological variables. Results: EpCAM is consistently expressed in the distal nephron on normal renal epithelium. Clear cell RCCs show minimal and infrequent EpCAM expression, whereas chromophobe and collecting duct RCCs both demonstrate intense and frequent expression. Of 318 clear cell carcinomas used in the analysis, 10% were EpCAM positive in ≥50% of cells, and 8% of patients would be considered candidates for EpCAM-based therapy, based on high expression [≥moderate intensity and frequent (≥50%) expression] and the need for systemic treatment. EpCAM expression was an independent prognostic factor for improved disease-specific survival, with a multivariate hazard ratio of 0.63 (P = 0.017; 95% confidence interval, 0.43–0.92). Conclusions: EpCAM is a novel prognostic molecular marker in RCC patients, and its positive expression is an independent predictor associated with improved survival. However, high expression in morphologically normal renal tissues and minimal or absent expression in clear cell carcinomas will likely limit the utility of this epithelial marker in targeted treatments of this most common RCC type.

Positron emission tomography in urologic oncology.

BACKGROUND Positron emission tomography (PET) is an emerging imaging modality that is being investigated for use in urologic oncology. PET scanning using the radioactive glucose analog FDG has proven to be a highly accurate imaging test for diagnosing and staging a variety of non-urologic cancer types. This review was performed to determine the role of PET imaging in genitourinary malignancies. METHODS A review of the literature focusing on PET and urologic oncology was performed. The role of PET imaging was reviewed in prostate, bladder, renal, and testicular cancer. RESULTS In testicular cancer, PET has a higher diagnostic accuracy than computed tomography (CT) for both staging and re-staging and should be the test of choice for the assessment of a CT-visualized residual mass following chemotherapy. In prostate, renal, and bladder cancer, the current role of PET is still being defined, but it has a high positive predictive value and can be used for problem solving in patients with indeterminate findings on conventional imaging. Its role in the diagnosis and staging of prostate cancer is hampered by the generally low glycolytic rate of most prostate tumors and their metastases. It has shown promise for staging and re-staging patients with advanced-stage disease and aggressive tumors suspected by a high tumor grade and high prostate-specific antigen velocity. PET has also demonstrated success when applied to renal cell carcinoma in classifying indeterminate renal masses as well as residual renal fossa masses following nephrectomy, gauging response to therapy, and staging and re-staging patients with a known diagnosis of renal cell carcinoma. CONCLUSIONS PET imaging has demonstrated great potential in certain applications, but further investigations are necessary to determine its eventual place as an imaging modality in genitourinary malignancies.

Pathobiology and prognosis of chromophobe renal cell carcinoma

OBJECTIVES To analyze pathobiology and prognosis of chromophobe renal cell carcinoma (CRCC). PATIENTS AND METHODS We studied 124 patients with CRCC who underwent nephrectomy from 1989 to 2006 at two institutions. Clinicopathological characteristics and survival were compared with 1,693 consecutive patients with clear-cell RCC. RESULTS Compared with clear cell RCC, patients with CRCC presented with less advanced tumors, but had a higher prevalence of concomitant sarcomatoid features (15% vs. 6%, P < 0.001). Metastatic CRCC showed a high incidence of sarcomatoid features (50%) and a predilection for liver metastases. The 5-year DSS rate for all patients with CRCC was 78% compared with 60% for patients with clear-cell RCC (P = 0.008). When adjusted for metastatic status, this survival difference disappeared. Nonmetastatic RCCs had similar prognosis (P = 0.157), whereas survival of metastatic CRCC was inferior to that of patients with metastatic clear-cell tumors (median: 6 vs. 19 months, P = 0.0095). In multivariate analysis, ECOG PS, symptomatic presentation, T stage, N stage, M stage, nuclear grade, and presence of sarcomatoid features, but not histological sub-type, were independent prognostic factors of DSS. Ten patients received immunotherapy, none of whom were responders. CONCLUSIONS Compared with clear-cell RCC, patients with CRCC present with less advanced tumors, which lead to better survival rates on the whole. However, adjustment for metastatic status negates this difference. Patients with metastatic CRCC show a high prevalence of sarcomatoid features, predilection for liver metastases, no response to immunotherapy, and exhibit poor prognosis.

Cystic renal cell carcinoma: biology and clinical behavior.

The purpose of the study was to evaluate unilocular and multilocular cystic renal cell carcinoma (cRCC). These tumors are a rare entity, comprising approximately 1 to 2% of all renal tumors, and their true biologic behavior is not well-known. Initial review of renal cell carcinoma (RCC) cases treated at our institution between 1989 and 2001 identified 39 cases of cRCC. However, histopathologic review of these cases by 2 pathologists revealed that only 18 cases met the criteria that all tumors have a cystic component that constitutes at least 75% of the total lesion without evidence of necrosis. These cases were compared to 614 conventional clear cell RCC cases with regards to clinical outcomes. All 18 patients presented with localized (N0M0) disease. Thirteen (72%) of the tumors were Fuhrman Grade 1, while the remaining 5 (28%) were Fuhrman Grade 2. By comparison, only 60% of the clear cell RCC tumors were Grade 1 or 2. Similarly, 83% of cRCC were pT1 tumors compared to only 35% of conventional clear cell tumors. Mean tumor size for the cRCC tumors was 4.9 cm compared to 7.4 cm for conventional clear cell tumors. Cystic RCC patients had an 82% four-year disease-specific survival (DSS). Unilocular and multilocular cRCC is a distinct subtype of clear cell RCC. Its biology appears to be more favorable with regards to important prognostic factors such as metastatic presentation, Fuhrman grade, 1997 T stage, and tumor size. These findings suggest that cRCC patients may benefit from nephron sparing surgery.

Prognostic factors and molecular markers for renal cell carcinoma.

Renal cell carcinoma is the most common cancer in the kidney, affecting nearly 30,000 Americans every year and is associated with over 12,000 deaths annually. If detected early, renal cell carcinomas can be cured surgically. However, once metastatic disease develops the prognosis for long-term survival is poor. Unfortunately, one-third of patients have metastatic disease at the time of diagnosis and approximately 50% of the patients undergoing surgical resection for less advanced disease eventually relapse. This review examines the clinical and molecular prognostic tools currently available or under investigation for kidney cancer.

Behçet's syndrome with left ventricular aneurysm and ruptured renal artery pseudoaneurysm.

A 21-year-old man with Behçets syndrome presented with both a left ventricular aneurysm and a left renal artery pseudoaneurysm. After successful embolization of the ruptured pseudoaneurysm, the patient underwent successful repair of the left ventricular aneurysm. Although multiple aneurysms have been reported previously, we believe this to be the first reported case of both a ventricular aneurysm and a renal artery pseudoaneurysm afflicting a patient with Behçets syndrome.

Emerging technologies in uroradiologic imaging

Advances in imaging technologies have readily been incorporated into the practice of urology and have led to important advances in patient care and outcomes. In the area of oncology, advances in radiologic imaging are improving the ability of the urologist to diagnose and monitor urologic malignancies. Some of these technologies include positron emission tomography (PET), intraoperative ultrasound (IUS), 3-dimensional computerized tomography (3D-CT), and magnetic resonance spectroscopy (MRS). We provide an overview of these four emerging imaging modalities and their potential applications and limitations in the diagnosis and management of urologic malignancy.