Incidence Of Local Metastasis Research Articles

Low local metastatic rate may widen indication of nephron-sparing surgery for renal cell carcinoma

To explore the rationale for renal-sparing surgery as an alternative method to radical nephrectomy in the treatment of renal cell carcinoma (RCC), we analyzed clinical data from 94 patients diagnosed as having RCC. They were divided into 3 groups based on the maximum diameter of their tumor specimens. Group A had tumors size ranging from 0 to 4 cm, group B had tumors size ranging from 4 to 7 cm, and group C had tumors size greater than 7 cm. Tissue samples (5 cm) were taken from the upper pole side, lower pole side, and renal pelvic side of the tumor pseudocapsule; if the tumor was located on 1 pole of the kidney, samples were collected from 2 directions. The specimens were then embedded in paraffin and cut serially at segments 0 to 1, 1 to 3, and 3 to 5 cm. Staining with hematoxylin and eosin, anti-pancytokeratin, and vimentin was performed to determine tumor type and tumor infiltration. From the 94 patients analyzed, 2 patients in group A had RCC metastasis within 1 cm of tissue around the pseudocapsule, and 4 patients in groups B and C had lymph node metastasis without metastasis in the tissue 1 cm outside the pseudocapsule in all 3 directions described. There was no statistical significant difference found between the incidence of local metastasis of the various tumor sizes, suggesting that local metastasis of RCC is not associated with the size of the tumor. Based on the observation that incidences of local metastasis were low in early-stage RCC, we came to the conclusion that pseudocapsule of RCC tumor might have growth-limiting effect on the tumor enclosed. It is theoretically a safer and better surgical option for patients with RCC with a smaller size of tumor and indications for radical nephrectomy to undergo renal-sparing surgery with an excision margin of 1 cm of normal tissue around the pseudocapsule of the tumor.

LOCAL METASTASIS AT THE TIME OF INITIAL DIAGNOSIS OF THYROID CANCER.542

Differentiated thyroid cancer is relatively uncommon in pediatrics and had a peak incidence around 1955. This peak is generally thought to be due to prior external beam radiation treatment. In 1960, Winship and Rosvoll reported data from 341 patients ≤ 15 years of age with thyroid cancer; 76% had local metastases (LM) at diagnosis. The current study was performed to determine if the frequency of LM at diagnosis might be lower in more contemporary patients. We reviewed the records of 120 thyroid cancer patients (diagnosed between 1953 and 1994) from the Department of Defense Centralized Tumor Registry. These patients were all ≤ 21 years of age at diagnosis. Histology revealed 83% papillary and 17% follicular. Of these, 50 (41.6%; 95% CI: 32.8 - 51.0%) had LM at diagnosis. We then excluded patients from our series who were over 15 years of age or diagnosed before 1970. Of the remaining 27 patients, 12 (44%; 95% CI: 25.7-64.0%) had LM at diagnosis. When compared to the study by Winship and Rosvoll, the incidence of LM in our series was significantly less(p=0.0008). In addition, when all of our data were analyzed according to the year of diagnosis, there was a trend (p=0.056) for decreased LM from 1953 to 1994. These data suggest the incidence of LM at the time of diagnosis of thyroid cancer may be declining in the pediatric age group. This could be due to less frequent exposure to ionizing radiation or to increased awareness and earlier detection.