No abstract

Primary benign vascular lesions of the kidney are uncommonly encountered in routine surgical pathology practice. They can, however, mimic malignancy or be an incidental finding adjacent to a malignancy. Fifteen specimens harboring 16 primary benign renal lymphatic/vascular lesions were identified from our files from 1999 to 2011 and subjected to a detailed pathologic evaluation and clinicopathologic correlation. Clinical and demographic data were available for all the 15 cases. There were ten males and five female patients with age range of 33-74 years (mean 54 years). Lesions ranged from 0.5 cm to 40 cm (average, 6.6 cm). There were six arteriovenous malformations (AVMs), four hemangiomas, three anastomosing hemangiomas, two lymphangiomas, and one solid intravascular papillary endothelial hyperplasia (IPEH). Five AVMs were located in the kidney parenchyma and one in the pelviureteric system. Additional associated lesions ranged from renal stones to renal cell carcinoma in two cases (one lymphangioma and one AVM). One AVM was associated with a capillary hemangioma in the vicinity, and another with a history of renal cell carcinoma in the contralateral kidney. Capillary hemangiomas and lymphangiomas were noninfiltrative and lacked cytological atypia and mitotic activity. Except for a renal pelvic AVM, all other renal AVMs radiologically mimicked malignancy. The patients had undergone partial or radical nephrectomies except for the renal pelvic AVM which was laparoscopically excised. To the best of our knowledge, none of the cases had any syndromic/systemic associations. Benign vascular lesions of the kidney are rarely seen in routine surgical pathology practice, partly because a vast majority of them are medically treated by embolization. However, lesions mimicking renal malignancy are subjected to surgery. They may exist as isolated lesions or coexist with malignant lesions either in the ipsilateral or the contralateral kidney.

We report the results of a large series of chain transplantations that were facilitated by a multicenter US database in which 57 centers pooled incompatible donor/recipient pairs. Chains, initiated by nondirected donors, were identified using a computer algorithm incorporating virtual cross-matches and potential to extend chains. The first 54 chains facilitated 272 kidney transplants (mean chain length = 5.0). Seven chains ended because potential donors became unavailable to donate after their recipient received a kidney; however, every recipient whose intended donor donated was transplanted. The remaining 47 chains were eventually closed by having the last donor donate to the waiting list. Of the 272 chain recipients 46% were ethnic minorities and 63% of grafts were shipped from other centers. The number of blood type O-patients receiving a transplant (n = 90) was greater than the number of blood type O-non-directed donors (n = 32) initiating chains. We have 1-year follow up on the first 100 transplants. The mean 1-year creatinine of the first 100 transplants from this series was 1.3 mg/dL. Chain transplantation enables many recipients with immunologically incompatible donors to be transplanted with high quality grafts.

We suggest that a general definition of fat poor angiomyolipoma should be the failure of imaging to reveal fat within a lesion, thus, making it unsuspected at surgery. A pathological definition should be less than 25% fat per high power field, which to our knowledge is a formerly undefined quantity. Not all cases are hyperdense on nonenhanced computerized tomography. These lesions cannot be reliably identified by imaging and they should be managed like all enhancing renal masses.

Larger kidney volumes calculated using 3-dimensional computerized tomography with volume calculating software are correlated with lower recipient nadir and 1-year serum creatinine levels.