Histomorphometric changes in the vessel wall at the site of amputation in diabetic patients--do they influence healing of the stump?

PURPOSE: To predict healing of the stump by assessing the microscopic vascular changes at the amputation site. METHODS: A cohort study was conducted on 39 patients, 18 of them had below-knee amputation (group A) and 21 had ray amputation of a single toe (group B). Biopsies were taken from the anterior and posterior tibial arteries and the venae comitantes of group A patients. For group B patients, biopsies of the digital artery and dorsal vein of the toe were taken. RESULTS: In group A, 15 patients required no further amputation (group A1) and 3 underwent a further above-knee amputation (group A2). In group B, 16 required no further amputation (group B1) and 5 underwent a below-knee amputation (group B2). Lumen narrowing caused by intimal thickening of the arteries was significantly different between groups A1 and A2 (p<0.05). Lumen narrowing of the dorsal veins between groups B1 and B2 was also significantly different (p<0.05). The proportion of the vessel walls made up of intima and media was significantly different in both A1 and A2 as well as B1 and B2 groups. The proportion of total wall thickness over the total diameter of the vessel was not significantly different between both subgroups of A and B. CONCLUSION: Intimal thickening and medial thinning in the arteries can be used to predict the stump healing in patients who underwent below-knee amputation. For ray amputation patients, similar changes occurred in the dorsal veins, and this finding can also be used to predict the healing of the stump. However, intimal thickening occurred at the expense of the media; therefore, there is little change in the wall thickness.

Targeted intra-operative radiotherapy (Targit): an innovative method of treatment for early breast cancer.

INTRODUCTION: We believe that conservative treatment of early breast cancer may not require radiotherapy that encompasses the whole breast. We present here the clinico-pathological basis for this view, as well as a novel therapeutic approach that allows intra-operative radiotherapy to be safely and accurately delivered to the target tissues in a standard operating theatre. THE RATIONALE: Whole-organ analysis of mastectomy specimens reveals that 80% of occult cancer foci are situated remote from the index quadrant. In contrast, over 90% of local recurrences after breast conservative therapy occur near the original tumour, even when radiotherapy is not given. Therefore, the remote occult cancer foci may be clinically irrelevant and radiotherapy to the index quadrant alone might be sufficient. A NOVEL TECHNIQUE: The Photon Radiosurgery System (PRS) is an ingenious portable electron-beam driven device that can typically deliver intra-operative doses of 5-20 Gy, respectively, to 1 cm and 0.2 cm from the tumour bed over about 22 min. The pliable breast tissue--the target--wraps around the source, providing perfect conformal radiotherapy. Being soft X-rays, the dose attenuates rapidly (alpha approximately 1/r3), reducing distant damage. RESULTS: In our pilot study of 25 patients (age 30-80 years, T = 0.42-4.0 cm), we replaced the routine post-operative tumour bed boost with targeted intra-operative radiotherapy. There have been no major complications and no patient has developed local recurrence, although the median follow-up time is short, at 24 months. CONCLUSION: It is safe and feasible to deliver targeted intraoperative radiotherapy (Targit) for early breast cancer. We have begun a randomised trial--the first of its kind--comparing Targit with conventional six-week course of radiotherapy. If proven equivalent in terms of local recurrence and cosmesis, it could eliminate the need for the usual six-week course of post-operative radiotherapy.