Florid hyperplasia of mesonephric remnants involving prostate and periprostatic tissue. Possible confusion with adenocarcinoma.

Two cases of florid hyperplasia of mesonephric remnants occurring in the prostate are described. One case was originally interpreted as invasive adenocarcinoma on transurethral resection (TUR), resulting in radical prostatectomy. In the second case, a TUR specimen was diagnostic for adenocarcinoma, which was confirmed in the radical prostatectomy specimen. Florid mesonephric hyperplasia in the second case was an incidental finding. The TUR specimen in the first case and sections of the prostatectomy specimens in both cases contained a proliferation of tubules, which ranged from aggregates of microacini to dilated structures containing a characteristic colloid-like material. The location of these lesions in the base of the prostate gland and periprostatic soft tissue suggests that these may be mesonephric remnants that have become hyperplastic. This type of lesion shares many features with mesonephric hyperplasia occurring in the female genital tract, including the presence of eosinophilic intratubular material and a lobular arrangement of microacini lined by a single layer of epithelium with prominent nucleoli. However, the latter feature, along with the apparent permeation of the prostatic fibromuscular stroma, periprostatic soft tissue, and even neural spaces, closely mimicked prostatic adenocarcinoma. In both cases, the proliferating tubules reacted with keratin 903 and were negative for prostate-specific antigen and prostate acid phosphatase, thereby excluding the diagnosis of prostatic adenocarcinoma. We concluded that lobular hyperplasia of mesonephric remnants is a distinct histologic entity that may occur in the prostate and periprostatic soft tissues and closely mimic prostatic adenocarcinoma.

Metastatic transitional cell carcinoma simulating primary ovarian malignancy.

A case of metastatic transitional cell carcinoma (TCC) to the ovaries in a patient with prior grade I TCC of the bladder, which morphologically resembled a primary ovarian malignancy on computed tomography (CT), is described. Other tumors whose ovarian metastases can resemble primary ovarian tumors are also listed.

Prostate cancer: correlation of MR images with tissue optical density at pathologic examination.

To explain the variability in detection of prostate cancer with magnetic resonance (MR) imaging, the authors correlated preoperative MR findings in 28 patients with tissue optical density (TOD) measurements on whole-mount pathologic slides prepared from radical prostatectomy specimens. TOD was used as an indicator of the degree of tissue compactness or openness. TOD measurements from proved cancers and from pathologic regions corresponding to MR lesions (areas of low signal intensity seen at T2-weighted MR imaging) were compared with TOD measurements from adjacent, nonmalignant tissue. TOD measurements corresponding to MR lesions were higher than noncancerous tissue measurements in all cases (P less than .005). Although most of these lesions represented cancers (21 of 30), nine of 30 represented benign tissue that was composed mainly of densely packed fibromuscular stroma (30% false-positive results). Thus, signal intensity appeared to be related to TOD rather than to a specific histologic tissue type, and the finding of a peripheral zone lesion with low signal intensity did not necessarily indicate the presence of a cancer.

Carcinoma of the prostate: MR images obtained with body coils do not accurately reflect tumor volume.

MR imaging with a body coil is unreliable in directly demonstrating tumor spread through the prostatic capsule. However, the likelihood of extracapsular spread of prostatic cancer rises with increasing tumor volume. The aim of our study was to assess the accuracy of MR with a body coil in diagnosing capsular penetration indirectly via an estimation of prostatic tumor volumes. Twenty-six patients with proved prostatic cancer that was clinically confined to the gland underwent MR imaging before radical prostatectomy and whole-mount pathologic sectioning of the specimen. Twenty of 31 lesions prospectively outlined on the MR images corresponded to cancers outlined on the pathology slides, and tumor volumes were calculated by using a voxel summation technique. On MR, tumor volume was underestimated in 11 of 20 cases and overestimated in nine of 20 cases. Only two of 20 size estimates based on MR findings were within 10% of actual tumor volume. Overlap in MR tumor volumes was significant between lesions with and without capsular penetration at microscopy. Factors contributing to inaccuracies in measurements of tumor volume on MR images included the variable histologic make-up of the tumors. Our results show that, although knowledge of the size of a prostatic lesion is important in predicting the behavior of the tumor, MR imaging with a body coil is not reliable for accurate estimation of tumor volume.

Urothelial carcinoma occurring within an inverted papilloma of the ureter.

Only 5 cases of inverted papilloma of the ureter with a malignant component have been reported previously. We add case 6 to the literature. The incidence of concomitant malignancy in ureteral inverted papillomas is 3 times that found in similar lesions occurring in the bladder.

In vivo and in vitro MR imaging of renal tumors: histopathologic correlation and pulse sequence optimization.

Magnetic resonance (MR) imaging has given mixed results in the detection of renal masses. To identify the reasons for this and to determine the optimal pulse sequences for evaluating renal tumors, the authors imaged 12 primary renal tumors in vivo and 17 in vitro at 0.35 T. Histopathologic findings for each specimen were closely correlated with the MR images. Four of seven solid tumors imaged in vivo were isointense with surrounding normal renal parenchyma at all pulse sequences. The other three tumors were hyperintense in vivo at T2-weighted sequences. At heavily T2-weighted sequences eight solid tumors were hyperintense in vitro and four were hypointense. There was no correlation between signal intensity and specific tissue type or histologic pattern for solid tumors. The five cystic tumors were well seen both in vivo and in vitro on T2-weighted images. However, the signal intensity of the cyst fluid was an unreliable indicator of benignancy. SE MR imaging at 0.35 T has significant limitations in the detection of solid renal masses.

Periarticular fibrosis associated with idiopathic retroperitoneal fibrosis.

We describe a previously unreported association of retroperitoneal fibrosis with biopsy proven periarticular inflammatory fibrosis. Histologic features were strikingly similar at the 2 sites. Plasma levels of a platelet derived growth factor, connective tissue activating peptide III, were found to be elevated and may play a role in pathogenesis. A dramatic response of the periarticular process to corticosteroids correlated with improvement of other variables of disease activity.

Ibuprofen-associated renal dysfunction. Pathophysiologic mechanisms of acute renal failure, hyperkalemia, tubular necrosis, and proteinuria.

Ibuprofen-associated, acute, reversible renal failure with hyperkalemia, tubular necrosis, and proteinuria developed in a patient who had no predisposing underlying disease. A renal biopsy specimen revealed mesangial hypercellularity without glomerular crescent formation. A profound interstitial nephritis with focal inflammatory cell infiltrates of predominantly mononuclear cells and neutrophils as well as focal tubular destruction was seen. Vasculitis was not observed. Ultrastructural studies confirmed the light microscopic diagnosis of a tubulointerstitial nephritis and, in addition, indicated the presence of electron-dense mesangial and subepithelial deposits. Direct immunofluorescence examination showed diffuse mesangial IgM and C3 deposition as well as vascular C3 deposition. Renal failure rapidly resolved after discontinuation of ibuprofen therapy and initiation of steroid therapy, with return to normal levels of serum creatinine, urea nitrogen, potassium, and sodium. Proteinuria also resolved.

Chemical ablation of the canine kidney using sodium tetradecyl sulfate (Sotradecol). A histopathologic study.

We studied the histopathologic effect of intraarterial Sotradecol (Elkins-Sinn, Inc., Cherry Hill, NJ) on the kidney and examined the mechanism for destruction of renal parenchyma by Sotradecol. Sotradecol was injected into one renal artery distal to an occlusion balloon catheter in six dogs, and the kidneys were removed for histologic examination; four dogs within 20 minutes, and one each at 12 and 24 hours after embolization. The contralateral kidney of each dog underwent the same procedure but was injected with normal saline, and served as control. Histologic examination of the control kidneys was unremarkable. The embolized kidneys revealed extensive endothelial denudation and mural necrosis of the arteries and coagulation necrosis of the renal parenchyma. The changes were evident as early as 20 minutes after embolization, and necrosis became complete by 24 hours. The arteries were filled with red blood cell sludge. Sotradecol produces extensive tissue necrosis and complete renal parenchymal destruction through its direct cytotoxic action on the arterial wall, blood cell elements, and renal parenchyma.

Alveolar soft part sarcoma of the uterine cervix.

Alveolar soft part sarcoma is a histologically distinctive neoplasm of uncertain histogenesis. Since its initial description in 1952, more than 200 cases have been reported. The extremities are most often the sites of involvement; the tongue, bones, and the orbit have been less commonly involved. The present paper describes a case of alveolar soft part sarcoma which was present only within the uterine cervix of a 37-year-old woman. Histologically, the tumor cells were arranged in the characteristic alveolar pattern; diagnostic PAS-positive diastase-resistant needle-shaped crystals were observed within the cytoplasm of the tumor cells. After the initial biopsy, the patient underwent a radical hysterectomy and pelvic lymph node dissection. Although no residual tumor was found within the cervix, a microscopic focus of tumor was detected in an obturator lymph node. The patient is at present clinically free of disease.

Computed tomography of renal oncocytomas.

A retrospective analysis of 5 renal oncocytomas studied with CT was performed. Oncocytomas appeared as rounded hypodense solid masses with sharp margination from the normal renal parenchyma. They showed uniform homogeneous enhancement on CT scans performed after drip infusion of urographic contrast. One oncocytoma studied with dynamic CT scanning demonstrated a stellate (spoke-wheel) pattern of enhancement. No evidence of involvement of adjacent renal parenchyma, perinephric fat, renal veins or regional lymph nodes was present at CT and the findings were confirmed at surgery. Although the differential diagnosis between renal oncocytoma and hypernephroma may not be possible, preoperative awareness of a potentially benign lesion may guide the surgeon to attempt renal preserving surgery instead of the customary nephrectomy.

Carcinosarcoma of bladder. Evaluation by electron microscopy and immunohistochemistry.

A case of carcinosarcoma of the urinary bladder characterized by electron microscopy and immunohistochemistry is described. The use of these studies in poorly differentiated bladder neoplasms and in suspected cases of carcinosarcoma is encouraged. Increased accuracy in characterizing these tumors will permit a better understanding of their natural history and response to therapy.

Incidental adenocarcinoma of the prostate: the role of repeat transurethral resection in staging.

Accurate staging of patients with incidental prostatic adenocarcinoma (A1 vs A2) is crucial to the selection of appropriate treatment. To evaluate the potential sampling error in specimens obtained by transurethral resection, repeat resection was performed on 31 patients pathologically staged as A1 (five or less chips with tumor). Second specimens showed no tumor in 22 (71%), stage A1 in six (20%), and stage A2 in three (9%). The weight of tissue removed at reresection was greater in patients found to have more extensive involvement (P less than 0.005). No patient with initial Gleason score 2, 3, or 4 had stage A2 at reresection. Repeat resection is not routinely necessary, but may be helpful when the tumor is high grade but of minimal extent, in an anxious younger patient who may wish therapy if disease persists, or where some suspicion of an incomplete resection exists.

Prolactin and growth hormone-producing pituitary adenomas. An immunohistochemical and ultrastructural study.

Thirteen prolactin and five growth hormone-producing pituitary adenomas were studied by immunohistochemistry and electron microscopy. The immunohistochemical localization of prolactin and growth hormone correlated well with elevated serum levels of pituitary hormones in all cases. Ultrastructural characterization by granule density and secretory activity was studied in relation to the serum levels of pituitary hormones and the sizes of the tumors. This indicated that markedly elevated serum hormone levels were related to larger tumors with high secretory activity, as indicated by abundant endoplasmic reticulum and well-developed Golgi complexes rather than to the numbers of cytoplasmic granules in the tumors. Two patients with prolactin-producing adenomas had been treated with bromocryptine before surgery. Both tumors showed evidence of degeneration, including cytoplasmic vacuolization. In one case the tumor had an increased number of secretory granules, while in the other case there were few viable cells and an abundance of amyloid deposits. The effects of bromocryptine therapy on pituitary tumor morphology in these two cases include an increased number of pituitary granules, and cellular degenerative changes.

Forensic aspects of the highway crash.

It can be stated that patterns of injury in highway crashes can often be related to specific design and damage features of the vehicle. The restraint systems designed to attenuate injury may also, under severe crash circumstances, produce trauma. Problems may arise as to identification of vehicular drivers. It behooves the pathologist concerned with the necropsy of crash victims and the physician responsible for treating crash victims to become familiar with the pathogenesis of injuries. Such knowledge can be utilized in the recommendation for improvement of vehicles to render them more crashworthy. Awareness of the various mechanisms of injury in vehicle crashes also enhances the diagnostic skill of the initial treating physician when he or she is confronted with a crash victim in the emergency department. Ideally, when the victim arrives at the hospital, the emergency room physician should be supplied with the details of the crash including the type of vehicle, position within the vehicle, use or nonuse of restraint systems, and the direction of the impact. When a fatality results from a car crash, ideally the autopsy pathologist should inspect the vehicle or at least view pictures of the exterior and interior of the vehicle to help establish the pathogenesis of injury in a specific collision. Unfortunately, because of time constraints, this ideal is not always achieved. Because of the considerable volume of civil and criminal litigation resulting from highway crashes, there is a need for competent medical expertise to help both the plaintiff and the defendent. The pathologist involved in forensic work and the treating physician play a particularly important role in the judicial arena.

Familial hyperuricemia and renal disease.

Information on a familial syndrome of hyperuricemia and renal disease with or without gout was obtained on 33 of 41 blood relatives: Nine had renal disease; abnormalities of the urinary sediments were minimal; serum uric acid levels were elevated in seven and were not measured in two. Hyperuricemia was noted in three additional family members without evidence of renal disease. Goulty arthritis (three patients) did not precede renal disease. One individual had hyperuricosuria. The following erythrocyte purine enzyme levels were normal: adenine phosphoribosyltransferase, hypoxanthine-guanine phosphoribosyltransferase, phosphoribosylpyrophosphate, synthetase, adenosine deaminiase, and purine nucleoside phosphorylase. Renal biopsy specimens showed focal global and segmental sclerosis of glomeruli, occasional hypercellularity, foci of atrophic tubules, chronic interstitial inflammation, and folding and wrinkling of glomerular basement membrane without electron-dense deposits. There were no immunofluorescent abnormalities.