Processing radical prostatectomies: an alternate-slice method is comparable with total embedding.

Receipt of radical prostatectomy specimens in the histopathology laboratory is quite common in academic centers and community hospitals. Despite numerous processing protocols, there is not an accepted standard method of processing. There are potential disadvantages of total sampling of the prostate; however, other alternatives have not been proven to show significant advantages. We present a partial sampling method (alternate slice) and compare its results to the total embedding method. Consecutive radical prostatectomy specimens were selected to compare both histologic sampling methods. The primary method of sampling was total embedding. Subsequently, alternate slice sections from the anterior, middle, and posterior thirds of the gland were reviewed. Seminal vesicle, bladder neck, and margins were similarly evaluated in both methods. Total sampling resulted in an average of 30 blocks compared with 18 in the alternate slice method. Gleason correlation was 87.5%; extraprostatic extension correlation was 97.9%. There was complete correlation in margin status and perineural invasion. Pathologic staging correlation was 97.9%. In summary, this alternate slice method compares very favorably with the total embedding method.

Case report: subcutaneous elemental mercury injection--clinical observations and implications for tissue disposal from the histopathology laboratory.

A 31-yr-old man presented to his general physician complaining of pain and swelling in the soft tissue of both hips. He initially denied knowledge of the etiology, but after elemental mercury droplets were expressed from the skin wounds by manual manipulation, he admitted that the source was self-administered sc injections. He did not provide a reason for this or give the time-frame of the injections. The areas of skin discoloration and soft tissue induration were completely excised and the wounds healed uneventfully. Blood levels of mercury declined gradually after excision. Examination of the resected skin and subcutis revealed subcutaneous abscesses containing droplets of elemental mercury, released easily when the abscesses were sectioned. Sections showed dark droplets of metallic mercury associated with necrosis and microabscess formation, with areas of foreign body giant cell reaction. Disposal of the residual tissues and mercury by incineration would release the volatile elemental mercury into the atmosphere, where it would subsequently be returned to earth in rain water, be converted to methyl mercury by microorganisms, and enter the food chain. The US Environmental Protection Agency has recommended caution in consuming foods containing methyl mercury and has provided guidelines for consuming foods believed to contain increased amounts of mercury. Mercury is readily available in the United States by over-the-counter sales to consumers, and in some cultures elemental mercury is used in ritualistic practices. Skin injection cases are infrequent, but histopathology laboratories should recognize this phenomenon and be prepared to dispose of Hg-contaminated tissues in an environmentally sound manner.

Gallbladder cystadenoma and common bile duct obstruction.

Cystadenomas are usually found in the extra-hepatic bile ducts in conjunction with multilocular cysts in the liver. Cystadenoma of the gallbladder itself is a rare finding, cited only once in the literature as the cause of extrinsic obstruction of the common bile duct (5). In this report, we describe the endoscopic retrograde cholangiopancreaticographic (ERCP) detection of intrinsic obstruction of the cystic duct and common bile duct by such a tumor in a 47-yr-old woman.

Cutaneous zygomycosis associated with urate panniculitis.

Cutaneous zygomycosis is being increasingly recognized as a serious and life-threatening infection in debilitated and immunosuppressed patients, including transplant patients. The organisms are morphologically distinct but difficult to grow in cultures from clinical samples. We report a case of cutaneous zygomycosis in a neonatal multi-visceral organ transplant patient, with subcutaneous panniculitis accompanied by extensive local acicular uric acid crystal deposition. Although the patient's serum uric acid was subsequently found to be in the normal range, transient hyperuricemia could not be excluded. Because we use a microwave-based processing system avoiding aqueous solutions, the crystals were maintained in the tissue sections and were shown by various methods to consist of monosodium urate. Early diagnosis combined with extensive debridement and prompt antifungal therapy resulted in a successful outcome. We have coined the term "urate panniculitis" to describe this phenomenon.

Sphenoid sinus chondromyxoid fibroma mimicking a mucocele.

We report the case of a 44-year-old man who presented with a chondromyxoid fibroma (CMF) of the sphenoid sinus, which filled the sinus and clinically and radiologically resembled a mucocele. Chondromyxoid fibromas are the least common cartilaginous neoplasms of bone, typically occurring in the metaphysis of long bones. They have occasionally been described in the facial bones, usually the mandible and maxilla, and rarely involve the paranasal sinuses. Chondromyxoid fibroma displays a relatively unique histological appearance, with characteristic lobulation, with spindle to stellate cells embedded in a myxoid or chondroid matrix. The periphery of the lobules tends to be more cellular than the center. Despite having been described nearly 60 years ago, the histogenesis of CMF remains controversial. Although CMFs are generally regarded as benign neoplasms, they may show an infiltrative pattern and may recur, particularly when they are in locations where complete surgical excision may be difficult or impossible.

Low-grade fibromyxoid sarcoma: a brief review.

Low-grade fibromyxoid sarcomas are uncommon deep soft tissue neoplasms first described by Evans in 1987. They exhibit a deceptively benign appearance, with a whorled or linear arrangement of spindle-shaped cells showing few to absent mitoses. A characteristic, but not specific, feature is the presence of areas of myxoid stroma. Recurrences are common, and late metastases have been recorded. A closely related but morphologically distinct tumor, the so-called hyalinizing spindle cell tumor with giant rosettes, has also been described; both neoplasms share the same cytogenetic abnormality, a balanced translocation resulting in a FUS/CREB3L2 fusion gene. Because of similar clinical behavior and the common cytogenetic abnormality, some authors prefer to consider both lesions as a single entity within the spectrum of low-grade sarcomas.

Angiotropism of human melanoma: studies involving in transit and other cutaneous metastases and the chicken chorioallantoic membrane: implications for extravascular melanoma invasion and metastasis.

Melanoma cell migration along the outside of vessels has been termed "extravascular migratory metastasis" (EVMM), as distinct from intravascular dissemination. Previous studies in both human and experimental melanoma models have shown angiotropism of melanoma cells, suggesting EVMM. Our objectives are to study the mechanism of dissemination of human melanoma cells in the chick chorioallantoic membrane (CAM) and to compare the histopathology in the CAM with that of patients with in transit and other cutaneous melanoma metastases. Human and murine melanoma cells were inoculated onto the CAM and observed over a 10-day period for tumor dissemination. Both human melanoma specimens from 26 patients and melanoma cells growing on the CAM showed the presence of tumor cell angiotropism at the invasive front of the tumor and at some distance from the tumor mass. In addition, a clear progression of melanoma cells spreading on the CAM was observed along the abluminal surface of vessels, where they occupied a perivascular location. By day 10 after injection, small micrometastases had developed along vessels, in a pattern similar to that in transit and other cutaneous melanoma metastases. In addition, the results suggested that the number of micrometastases directly correlated with increasing tumor volume. Taken together, these data suggest that the CAM is a relevant model for studying tumor cell dissemination, and that EVMM may be a mechanism by which some melanoma cells spread to nearby and even distant sites.

Angiotropism of human prostate cancer cells: implications for extravascular migratory metastasis.

OBJECTIVES: To report several samples of invasive human prostate cancer showing angiotropism, and to use human prostate cancer cells stably expressing green fluorescence protein (GFP) in in vitro and in vivo models to assess the dissemination pathway of prostate cancer cells. MATERIALS AND METHODS: Malignant melanoma and prostate carcinoma cells can migrate along anatomical structures such as nerves; previous studies showed that melanoma cells can be perivascular, on the outside of the endothelium, i.e. they are angiotropic, which suggests the hypothesis that melanoma cells also may migrate along vascular channels, termed 'extravascular migratory metastasis' (EVMM). Thus we examined histologically 10 human prostatic carcinoma specimens for the presence of angiotropism. In vitro, the PC-3 prostate cancer cells were co-cultures with capillary-like structures. In vivo, PC-3 cells were implanted on the chick chorio-allantoic membrane (CAM). RESULTS: Histologically, in all 10 cases, angiotropism was detected at least focally within the tumour or at the advancing front of the tumour. In vitro, the PC-3 cells spread along the external surface of the vascular tubules; in vivo, PC-3 cells formed a cuff around some vessels a few millimetres beyond the tumour, showing angiotropism. Histopathology of the CAM confirmed the perivascular location of tumour cells and the absence of tumour cells within the vessel lumina. CONCLUSION: The presence of angiotropic tumour cells in human invasive prostate cancers, associated with the angiotropism of GFP prostate cancer cells cultivated in vitro and in vivo in angiogenic models, raises the possibility that some prostate tumour cells may migrate along the external surface of vessels as a mechanism of spread, i.e. EVMM.