The role of intraabdominal pressure in venous blood drainage from the prostate into the vertebral vein system

Correlation of Peripheral Vein Tumour Marker Levels, Internal Iliac Vein Tumour Marker Levels and Radical Prostatectomy Specimens in Patients with Prostate Cancer and Borderline High Prostate-Specific Antigen: A Pilot Study

PURPOSE

To correlate prostate-specific antigen (PSA), free to total PSA percentage (fPSA%) and prostatic acid phosphatase (PAP) levels from peripheral and pelvic venous samples with prostatectomy specimens in patients with prostate adenocarcinoma and borderline elevation of PSA.

MATERIALS AND METHODS

In this prospective institutional review board approved study, 7 patients with biopsy proven prostate cancer had a venous sampling procedure prior to prostatectomy (mean 3.2 days, range 1-7). Venous samples were taken from a peripheral vein (PVS), the right internal iliac vein, a deep right internal iliac vein branch, left internal iliac vein and a deep left internal iliac vein branch. Venous sampling results were compared to tumour volume, laterality, stage and grade in prostatectomy surgical specimens.

RESULTS

Mean PVS PSA was 4.29, range 2.3-6 ng/ml. PSA and PAP values in PVS did not differ significantly from internal iliac or deep internal iliac vein samples (p > 0.05). fPSA% was significantly higher in internal iliac (p = 0.004) and deep internal iliac (p = 0.003) vein samples compared to PVS. One of 7 patients had unilateral tumour only. This patient, with left-sided tumour, had a fPSA% of 6, 6, 6, 14 and 12 in his peripheral, right internal iliac, deep right internal iliac branch, left internal iliac and deep left internal iliac branch samples respectively. There were no adverse events.

CONCLUSION

fPSA%, unlike total PSA or PAP, is significantly higher in pelvic vein compared to peripheral vein samples when prostate cancer is present. Larger studies including patients with higher PSA values are warranted to further investigate this counterintuitive finding.

Extraglandular and intraglandular vascularization of canine prostate

The literature on the vascularization of the canine prostate is reviewed and the clinical significance of prostate morphology is described. Scanning Electron Microscopy (SEM), combined with improved corrosion casting methods, reveal new morphological details that promise better diagnostics and treatment but also require expansion of clinical nomenclature. A proposal is made for including two previously unnamed veins in Nomina Anatomica Veterinaria (NAV). The canine prostate has two lobes with independent vascularization. Each lobe is supplied through the left and right a. prostatica, respectively. The a. prostatica sprouts three small vessels (cranial, middle, and caudal) towards the prostate gland. A. prostatica is a small-size artery whose wall structure is similar to the arteries of the muscular type. V. prostatica is a small-size valved vein. The canine prostate has capsular, parenchymal, and urethral vascular zones. The surface vessels of the capsule are predominantly veins and the diameter of arterial vessels is larger than that of the veins. The trabecular vessels are of two types: direct and branched. The prostate parenchyma is supplied by branches of the trabecular vessels. The periacinary capillaries are fenestrated and form a net in a circular pattern. The processes of the myoepithelial cells embrace both the acins and the periacinar capillaries. In the prostate ductal system. there are spermatozoa. The prostatic part of the urethra is supplied by an independent branch of a. prostatica. The prostatic urethral part is drained by v. prostatica, the vein of the urethral bulb and the ventral prostate veins. M. urethralis begins as early as the urethral prostatic part. The greater part of the white muscle fibers in m. urethralis suggest an enhanced anaerobic metabolism.

Myelophthisis as a solitary manifestation of failure from rectal carcinoma. A Batson phenomenon?

Rectal carcinoma is uncommonly associated with systemic metastases in the absence of liver metastases, reflecting the predilection for spread via the portal system. Occasionally, isolated lung metastases are seen, which are usually attributed to spread via the portosystemic anastomoses in the distal rectum. However, myelophthisis is an unreported complication of rectal cancer as an isolated form of systemic failure. We present a case of fatal myelophthisis associated with otherwise localized rectal carcinoma secondary to metastatic rectal cancer. This observation led to the hypothesis that spread to the bone marrow occurred via a "third circulation," the Batson plexus, a network of deep pelvic veins with rich anastomoses to the vertebral plexus.

Pattern of prostate cancer metastasis to the vertebral column

We examined 34 thoracic and lumbar vertebrae in eight patients with prostate cancer to elucidate the pattern of metastasis to the vertebral column. Computed tomography of thoracic and lumbar vertebrae was performed before treatment for the prostate cancer. Metastatic lesions were confirmed both by the recognition of osteoblastic and/or osteolytic lesions on CT and by histological identification at autopsy. Localized metastatic lesions were observed mostly in the peripheral rather than the central part of the vertebral body. There were no differences in distribution of lesions between the anterior and posterior parts of the vertebral body. There was no primary involvement of tumor in the spinous and transverse processes. These findings indicated that the major metastatic pathway to the vertebral column is via the vertebral venous system, and it appears that prostate cancer cells first metastasize to the vertebral body and then spread secondarily to the processes or other vertebrae.