Preoperative predictors of cancerous involvement of the neurovascular bundles in patients with localized prostate cancer

BACKGROUND: The purpose of this study was to identify preoperative variables that would be useful in objectively selecting prostate cancer patients for nerve-sparing prostatectomy. METHODS: Twenty-six patients with clinical T1c-T2c cancers were evaluated for cancerous involvement in the region of the neurovascular bundles (NVB) from prostatectomy specimens. Preoperative prostate-specific antigen (PSA) and pathologic features in systematic biopsy specimens also were reviewed. RESULTS: A total of eight (31%) patients had cancerous involvement in the region of the NVB, including four on the right side, three on the left side and one on both sides. The percentage of each biopsy specimen occupied by the cancer was scored from zero to four and defined as the positive biopsy score. Preoperative PSA (P = 0.046), mean positive biopsy score (total sum of positive biopsy score divided by number of biopsy specimens; P = 0.001), number of cores containing cancer (P = 0.011), percentage of cores involved (P = 0.036) and maximum positive biopsy score (P < 0.001) were significant for predicting cancerous involvement in the NVB region using univariate analysis. However, only the mean positive biopsy score was independently significant according to multivariate analysis. To predict cancerous involvement in the region of each NVB, we found that ipsilateral mean positive biopsy score (total sum of corresponding positive biopsy score divided by number of ipsilateral biopsy specimens), number of cores involved on the ipsilateral side, percentage of cores involved on the ipsilateral side and maximum positive biopsy score on the ipsilateral side were significant predictive variables: the ipsilateral mean positive biopsy score being most appropriate for clinical practice. CONCLUSION: Ipsilateral mean positive biopsy score in systematic biopsy specimens can be an appropriate variable for selecting patients with localized prostate cancer for nerve-sparing prostatectomy.     

Longitudinal study on occlusal force distribution in lower distal-extension removable partial dentures with circumferential clasps

In this study, longitudinal changes of the occlusal force distribution ratio were examined in lower distal extension removable partial dentures with cast circumferential clasps. Occlusal force applied to the denture base and forces transmitted to the retainers were measured on several separate occasions from the insertion of new dentures to about 4 months after. Two rates of loading were chosen. One was simulated mastication (fast loading rate) and the other was 10 Ns-1 (slow loading rate). Location of the loading points were first premolar (P1), second premolar (P2) and first molar (P3) of the denture. The occlusal force distribution ratio to the retainers was calculated when a load of 20N was applied to the loading point. The results are summarized as follows: (1) The occlusal force distribution ratio at fast loading rate on P1 and P2 was changed until 1 or 1 1/2 months after the insertion of the new dentures, and then became constant. This constant value was 30% on P1, 20% on P2 and 10% on P3. (2) Slow loading rate produced a greater ratio than the fast loading rate on P2 and P3 while there were no remarkable differences in the ratio between both loading rates on P1.     

Echographic Diagnosis of Soft Tissue Tumors in Extremity and Trunk: --Its Clinical Application in Orthopedic Surgery--

In the field of orthopedics, the echographic examination ofsoft tissue tumors by B-mode contact compound scanning is auseful clinical modality. Characteristics of the tumor, suchas whether it is cystic or solid, its border regular or irregular,and delineation of tumor size in three dimensions can be determined.The relationship between the tumor mass and the skin, musclelayer, connective tissue and periosteum can be defined preoperatively.Furthermore, it can be used for an echographic evaluation oftumor regression during antineoplastic treatment with chemotherapyor radiation therapy. Typical echograms of liposarcoma, chordoma,neurinoma, desmoid tumor, rhabdomyosarcoma and gluteal tumor,metastatic lesions from melanoma, lung and skin were demonstrated.The usefulness of this technique in the field of orthopedicsurgery is discussed with a review of literature.     

Renal cell carcinoma in dialysis patients: A single center experience

AIM: Renal cell carcinoma (RCC) is a life-threatening complication of end-stage renal disease with an unclear pathogenesis. We evaluated RCC developing in patients undergoing dialysis. METHODS: In 2624 patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis at our hospital between July 1993 and March 2004, we performed annual screening for RCC using abdominal computed tomography and ultrasonography. Patients diagnosed with RCC underwent radical nephrectomy as well as clinical and pathologic evaluation. RESULTS: RCC was detected in 44 patients (1.68%; 31 males and 13 females). The age of RCC patients was 55.5 +/- 11.1 years. Dialysis duration before RCC diagnosis was 11.2 +/- 7.2 years. Most RCC were early stage and low stage by TNM classification, 43 patients had N0M0 RCC, whereas one had N1M0. Tumor size was 2.9 +/- 1.9 cm. The predominant histological type of RCC was common or conventional cell-type carcinoma (clear cell carcinoma and granular cell carcinoma). Of patients, 5(11.4%) had bilateral RCC, and satellite tumor lesions in RCC were detected in 13 (29.5%). In 36 patients (81.8%) RCC was accompanied by acquired cystic disease of the kidney. These patients had longer dialysis durations (P = 0.01) and smaller tumors (P = 0.048). RCC metastasized postoperatively in 4 patients (9.1%), while one (2.3%) died of cancer. CONCLUSIONS: Our dialysis patients showed a higher incidence of RCC than the general population. Prognosis was favorable because tumors were detected by screening when they were small. Therefore, periodical screening for RCC seems very important in dialysis patients.     

Longitudinal study on occlusal force distribution in lower distal-extension removable partial dentures with conus crown telescopic system

The purpose of this study was to examine longitudinal changes of the occlusal force distribution in lower distal-extension removable partial dentures with the conus crown telescopic system. Occlusal force applied to the denture and forces transmitted to the retainers were measured on several separate occasions from the insertion of new dentures to about 3 months after. The occlusal force distribution ratio to the retainers was calculated when a load of 20N was applied to the denture.
The results are summarized as follows:

• (i)

    The more posterior the loading point of occlusal force, the smaller was the ratio. When the occlusal force was applied to the most anterior artificial tooth, the ratio was 65-100% of the occlusal force.
• (ii)

    As the denture wearing time proceeded, the ratio was decreased. The smaller the ratio, the greater was the rate of its decrease.