Paneth cell-like change and small cell carcinoma of the prostate. Two divergent forms of prostatic neuroendocrine differentiation

Paneth cell-like change of the prostate refers to collections of prostatic cells with eosinophilic cytoplasmic granules that bear a striking histological resemblance to normal intestinal Paneth cells. Paneth cell-like change in malignant prostatic epithelium usually represent neuroendocrine differentiation, with neuroendocrine granules confirmed by immunohistochemical and ultrastructural studies. We report the histopathological, immunohistochemical, and electron microscopic findings in a mixed adenocarcinoma with Paneth cell-like change and small cell undifferentiated carcinoma. This case illustrates two divergent forms of neuroendocrine differentiation occurring in a single prostatic neoplasm. The spectrum of neuroendocrine differentiation in the prostate should be expanded to include tumors with Paneth cell-like change in addition to carcinoid tumors and small cell undifferentiated carcinoma. These three distinct forms of prostatic neuroendocrine neoplasia appear to correlate with three size ranges of neuroendocrine granules seen by electron microscopy.

Prostatic tissue in mature cystic teratomas of the ovary

We report two examples of mature cystic teratomas of the ovary containing prostatic tissue. Both were incidental findings in teratomas that were otherwise typical at clinical and pathologic levels. The prostatic tissue contained ducts and acini in a simple branching pattern similar to that seen in the peripheral zone of the prostate gland. Transitional cell elements were present in both cases and compact acini resembling Cowper's gland were noted in one. No testicular or Wolffian duct tissue was noted. The immunohistochemical staining pattern of the glands was identical to that seen in normal prostate. In a literature review, four additional cases were identified. The presence of prostatic tissue in a 46XX tumor suggests induction by locally produced androgen. Some investigators have identified luteinized stromal cells and indicated these as the source of this androgen. Other possible androgenic origins include ovarian hilar cells, adrenal cortex, and tumor cells.

Prostate cancer presenting with malignant ascites: signet-ring cell variant of prostatic adenocarcinoma

A case of prostate cancer presenting with malignant ascites as the sole clinical manifestation is reported. The clinical course simulated occult gastrointestinal malignancy. At the histologic level, the tumor had a signet-ring morphology. Detailed immunocytochemical and ultrastructural studies, however, confirmed the prostatic origin of this neoplasm. Signet-ring carcinoma of the prostate is a rare aggressive form of prostatic cancer which may present with a malignant effusion and may mimic gastrointestinal cancer.

Mediastinal large-cell lymphoma

The records of 20 patients with pathologically diagnosed mediastinal large-cell lymphoma with sclerosis, a recently documented but uncommon subtype of mediastinal non-Hodgkin's lymphoma, were retrospectively reviewed to determine the clinical and radiologic features of the condition at the time of presentation. The disease was staged according to the Ann Arbor classification: 15 patients presented in clinical stage I or II and 5 in clinical stage III or IV. The patients, 6 women and 14 men, ranged in age from 15 to 63 years (mean = 31 years). Chest pain (experienced by 10 patients), dyspnea (by 9) and cough (by 7) were the most common clinical features. Obstruction of the superior vena cava occurred in seven patients. The mediastinal masses were large (the mean diameter was 10.8 cm) and located anteriorly (prevascularly). They contained low-attenuation areas and were often associated with other sites of mediastinal adenopathy. The initial pathologic diagnosis was incorrect for eight patients (40%). Mediastinal large-cell lymphoma can be added to the differential diagnosis of a large anterior mediastinal mass with obstruction of the superior vena cava.

Sclerosing adenosis of the prostate gland. A lesion showing myoepithelial differentiation

Sclerosing adenosis of the prostate is a rare lesion characterized by the proliferation of variably sized glands in a cellular stroma. We report light microscopic, immunohistochemical, and ultrastructural studies in 22 examples from 15 patients. Two cases were identified in 100 consecutive prostates embedded by a whole organ method, giving a prevalence of 2%. Antibodies directed against the following antigens were used: high-molecular-weight cytokeratin (CKH; 34 beta E12); cytokeratin (CK; AE1/AE3), prostatic acid phosphatase (PAP), prostate-specific antigen (PSA), S-100 protein, muscle-specific actin (HHF35), and vimentin (Vim). Cells within the glandular component demonstrated positive reactivity for CK, CHH, PSA, and PAP, indicating a prostatic epithelial origin. In addition, a distinct population of cells reacting for muscle-specific actin and S-100 protein was identified within this glandular element. Adequate material for ultrastructural study was available in five cases; all showed the presence of flattened cells located between the basement membrane and secretory epithelial cells, which had features typical for myoepithelial differentiation. Although the prostate gland does not normally contain myoepithelial cells, we have documented their consistent presence in this unusual lesion; we believe these cells arise by a metaplastic process from the prostatic basal cells.

Adenomatous hyperplasia of the rete testis. A clinicopathologic study of nine cases

Adenomatous hyperplasia of the rete testis is an uncommon lesion that has recently been described. Nine cases of adenomatous hyperplasia were identified in two institutions from 1980 to 1989. At diagnosis the nine patients ranged in age from 30 to 74 years (mean, 59 years; median, 66 years). Three patients presented with a grossly identifiable solid or cystic testicular hilar mass. In six cases adenomatous hyperplasia was an incidental microscopic finding--five from orchiectomy specimens and one from an autopsy specimen. Microscopically, the hyperplasia consisted of a tubulopapillary epithelial proliferation of rete testis. The lining cells were cuboidal to low columnar and lacked nuclear pleomorphism or mitotic figures. The involvement of the rete testis was predominantly diffuse. In seven cases the seminiferous tubules showed atrophic changes. Ultrastructural and immunohistochemical (keratin, epithelial-membrane antigen: positive; vimentin, muscle-specific actin, desmin, and S-100: negative) studies done on one case showed similar features to those of nonhyperplastic rete testis epithelium. No patient with adenomatous hyperplasia showed local recurrence or metastasis. Possible pathogeneses include hormonal imbalance or stimulatory influence that remains as yet unidentified.

In situ adenocarcinoma ex pleomorphic adenoma of the lacrimal gland

We report a unique case of in situ adenocarcinoma ex pleomorphic adenoma of the lacrimal gland. The patient is alive and disease-free 2 1/2 years after complete local excision of the tumour. The current clinicopathologic status of this unusual tumour is discussed in the context of the reported experience to date.

Basal epithelial cells of human prostate gland are not myoepithelial cells. A comparative immunohistochemical and ultrastructural study with the human salivary gland

The hypothesis that basal epithelial cells of the human prostate are of myoepithelial origin was investigated using immunohistochemical and ultrastructural methodologies. The immunohistologic analyses show significant phenotypic differences between prostatic basal cells and myoepithelial cells of the salivary gland. Although both cell types stain intensely with the 312C8-1 monoclonal antibody, only true myoepithelial cells demonstrated significant amounts of muscle-specific actin as decorated by the HHF35 monoclonal antibody. Furthermore, using double-labeling experiments, the prostatic basal cells were strongly decorated with a fluorescein-tagged basal cell-specific keratin but were negative with the rhodamine-tagged phalloidin, a chemical that binds specifically to actin microfilaments. Ultrastructural studies also showed an absence of thin microfilament bundles, dense bodies, and micropinocytotic vesicles in the prostatic basal cells. The current investigations show that the prostatic acini do not have a basal myoepithelium. Although some authors have suggested a stem cell role for prostatic basal cells, the weight of experimental work argues against this hypothesis. The exact role of the basal epithelial cells of the prostate is not known, although they may serve endocrine, paracrine, or other regulatory functions and may be involved in modulating signals between prostatic stroma and epithelium.

Basal epithelial cells of human prostate gland are not myoepithelial cells. A comparative immunohistochemical and ultrastructural study with the human salivary gland

The hypothesis that basal epithelial cells of the human prostate are of myoepithelial origin was investigated using immunohistochemical and ultrastructural methodologies. The immunohistologic analyses show significant phenotypic differences between prostatic basal cells and myoepithelial cells of the salivary gland. Although both cell types stain intensely with the 312C8-1 monoclonal antibody, only true myoepithelial cells demonstrated significant amounts of muscle-specific actin as decorated by the HHF35 monoclonal antibody. Furthermore, using double-labeling experiments, the prostatic basal cells were strongly decorated with a fluorescein-tagged basal cell-specific keratin but were negative with the rhodamine-tagged phalloidin, a chemical that binds specifically to actin microfilaments. Ultrastructural studies also showed an absence of thin microfilament bundles, dense bodies, and micropinocytotic vesicles in the prostatic basal cells. The current investigations show that the prostatic acini do not have a basal myoepithelium. Although some authors have suggested a stem cell role for prostatic basal cells, the weight of experimental work argues against this hypothesis. The exact role of the basal epithelial cells of the prostate is not known, although they may serve endocrine, paracrine, or other regulatory functions and may be involved in modulating signals between prostatic stroma and epithelium.

Transrectal fine-needle aspiration and truecut needle biopsy of the prostate: a blinded comparison of accuracy

Transrectal needle aspiration biopsy and core biopsy of the prostate were performed simultaneously on 88 men with prostatic nodules. Cytologic and histologic assessments were made in a blinded, independent fashion, and the results were compared. All patients with positive findings on aspiration also had positive findings on core biopsy, for a positive predictive value for aspiration of 100%. However, five negative and six "insufficient" results obtained by aspiration were positive on core biopsy, for a negative predictive value for aspiration of 88%. This experience support the use of needle aspiration as an initial diagnostic maneuver in the assessment of prostatic nodules.

Small-acinar patterns in the prostate gland with emphasis on atypical adenomatous hyperplasia and small-acinar carcinoma

A number of anatomic structures and pathophysiologic processes can mimic small-acinar carcinoma of the prostate gland. Seminal vesicles, ejaculatory ducts, and Cowper's glands can, at times, enter into the differential diagnosis of adenocarcinoma. Likewise atrophy, postatrophic hyperplasia, and some variants of central nodular hyperplasia can present a troubling small-acinar pattern. Another common proliferation referred to as atypical adenomatous hyperplasia lies on a morphologic continuum with low-grade acinar carcinoma and is thought by many investigators to be premalignant. Its distinction from minimal-deviation adenocarcinoma is made on the basis of both architectural and somewhat arbitrary nuclear criteria. When encountered alone, atypical adenomatous hyperplasia alerts the pathologist to examine all tissue, as it is a frequent accompaniment of well-differentiated adenocarcinoma. Once a diagnosis of low-grade acinar carcinoma has been made, accurate pathologic staging, especially in conjunction with clinically unsuspected disease (stage A), is extremely important in treatment planning and prognostication.

Atypical spindle cell lesions of the prostate

This report is a review of the spectrum of prostatic spindle cell lesions that are usually benign, but have morphologic features suggestive of high-grade malignancy. The problem is complicated further by the extreme rarity and heterogeneity of such lesions. Sixteen cases of atypical prostatic spindle cell proliferations are reported, and the differential diagnosis with malignancy is reviewed.

Selected ultrastructural aspects of urothelial and prostatic tumors

Ultrastructural techniques have been widely applied in the study of urothelial and prostatic tumors. In the common proliferative diseases affecting the lower urogenital tract, electron microscopy has provided us with a greater understanding of the pathobiology and morphology of these disease processes. Specific diagnostic application, however, has been limited. In the unusual tumors affecting urothelium and prostate such as neuroendocrine carcinoma, carcinosarcoma, and sarcomas, electron microscopy has provided some practical diagnostic information of value in patient management. This paper provides a survey of the fundamental and practical contributions of ultrastructural studies in the prostatic and urothelial areas.

The ultrastructure and histogenesis of male germ neoplasia with emphasis on seminoma with early carcinomatous features

The range of ultrastructural morphology was studied in 107 male germ cell neoplasm to assess relationships among tumor subtypes and to consolidate diagnostic criteria. Eighty-three pure-pattern neoplasms including 47 seminomas, 26 embryonal carcinomas, 10 endodermal sinus tumors, and 24 mixed germ cell tumors were analyzed. In the seminoma category, 4 cases showing cell surface specialization in keeping with early carcinomatous transformation were noted. The finding suggested a closer link between seminoma and nonseminomatous germ cell tumors than had been traditionally recognized and was in keeping with other clinical, histologic, biochemical, and xenograft observations. Subtypes of nonseminomatous germ cell tumors also exhibited a continuum of ultrastructural morphology with some types such as embryonal carcinoma and endodermal sinus tumor often blending together. At a practical level, electron microscopy has been of value in selected differential diagnoses such as seminoma versus lymphoma.

Diagnostic electron microscopy of male genital tract tumors

As illustrated in this review, neoplasms of the male genital tract are markedly heterogenous, reflecting their complex embryologic derivation and histogenetic classification. Transmission electron microscopy has greatly increased our understanding of the structure of these tumors, and in doing so has greatly improved our light microscopy. Additionally, in a number of selected situations, TEM also provides important practical diagnostic information. Currently, light microscopy in conjunction with clinical information is the central tool of tumor taxonomy. However, TEM with histochemistry, immunohistology, analytic cytometry, and molecular biology provide practical and useful information in some situations. In all cases, the application of these techniques has greatly increased our overall understanding of tumor structure, pathobiology, and classification.

Diffuse epithelial mesothelioma: a review of the ultrastructural spectrum

Traditionally, diffuse epithelial mesotheliomas are mainly identified at the ultrastructural level by the numerous, long, wavy-appearing surface microvilli. By electron microscopy of a series of diffuse mesotheliomas of varying subtype (epithelial, biphasic, sarcomatous, and poorly differentiated), it can be demonstrated that the differentiation of this specialized surface organelle is quite variable even in well-differentiated lesions. The presence of only a few, scattered, short microvilli does not exclude a diagnosis of epithelial mesothelioma, particularly if historical, surgical, and radiologic findings support this diagnostic conclusion. Indeed, even the complete absence of surface microvilli is compatible with a diagnosis of diffuse epithelial mesothelioma. It is important to become aware of the spectrum of tumor cell differentiation in serosal tumors, as all of the fine structural diagnostic criteria in mesotheliomas are expressed to varying degrees in individual cases.

Clear cell cribriform hyperplasia of prostate. Report of 10 cases

We report 10 patients with clear cell cribriform hyperplasia of the prostate. Their ages ranged from 62 to 87 years, with a mean of 72 years. The clinical diagnosis in all patients was benign nodular hyperplasia; all the patients are alive and have shown no evidence of recurrent disease. Follow-ups ranged from 1 month to 7 years (median: 12.5 months; mean: 24.6 months). Pathologically, this lesion has a cribriform arrangement of clear cells with a complex papillary growth simulating the cribriform pattern of prostatic carcinoma. In fact, in five of the 10 cases, the referring diagnosis was either carcinoma or possible carcinoma. Cytologically, however, there is no nuclear atypia, mitosis, or prominent nucleoli, and typically there is a double epithelial cell layer at the periphery of the involved acini. In summary, clear cell cribriform hyperplasia is a benign hyperplastic process with a complex papillary-cribriform structure and should not be confused with prostatic carcinoma. The key feature for the diagnosis is the preservation of nodular configuration with a bland cytology and double cell layer lining the involved acini.

Nucleic acid cytometry of homosexual-associated lymphoproliferative disease

Twenty-six reactive lymph nodes and 5 malignant lymphomas from homosexual males were studied by acridine orange flow cytometry (AO-FCM) for determination of ploidy, proliferation, and RNA characteristics. Two reactive lymph nodes showed ploidy abnormalities as compared with none of 27 reactive lymph nodes from nonhomosexual patients. The homosexual-associated (HA) lymphadenopathy had a higher mean proliferative activity (11.2% versus 5.6%) and higher ribonucleic acid (RNA) content (1.11 versus 0.96) than non-HA counterparts. The proliferative activity of HA lymphadenopathy was also higher than follicular small cleaved cell lymphoma, and not dissimilar to that of follicular large cell lymphoma. These findings indicate that HA-reactive lymphadenopathy is a hyperproliferative state associated with high cellular RNA content and rare DNA-abnormal stemlines. One HA lymphoma had an abnormal stemline by AO-FCM, compared with 9 of 15 (63%) non-HA high grade lymphomas. This lymphoma also demonstrated an abnormal karyotype (47,XY, +12, t[8;22]) by classic cytogenetic studies. The mean proliferative activity and RNA content of HA lymphomas was higher than non-HA counterparts (37% versus 22.5% and 2.48 versus 1.73, respectively). The proliferation and RNA features of HA lymphoma were on higher planes than non-HA lesions histologically comparable. Thus, in addition to differences in clinical presentation, histologic subtype, stage distribution, and therapeutic response, HA lymphomas have DNA/RNA characteristics different from those of counterparts in the general population.

Localized fibrous tumour of serosal surfaces. Immunohistochemical and ultrastructural evidence for a type of mesothelioma

It is uncertain whether localized lesions of serosal membranes have a kinship to mesotheliomas or are truly fibromatous in nature. Ultrastructural and immunohistochemical investigations were carried out on 12 localized benign and malignant pleural and peritoneal tumours from 10 patients. Electron microscopic findings, including the consistent and non-fibroblastic cellular organization of localized neoplasms, the presence of some form of intercellular junctions in 7 of 10 cases, basal lamina deposition in 3 cases, and polarized microvilli in one case indicated a form of mesothelial differentiation. Using monoclonal and polyclonal antibodies, positive immunostaining of tumour cells for cytokeratin peptides was detected in one case, while antibody to vimentin stained four cases. Light microscopic, ultrastructural and immunohistochemical features of one benign localized serosal tumour, with a unique blend of epithelial and spindle cells, provided further evidence for a histogenic link between localized serosal tumours and diffuse epithelial mesotheliomas. On the basis of the current findings and reports in the literature, it would appear that the majority of localized tumours of serosal membranes are a subset of mesothelioma, while a minority are fibromas.

Q-fever. The liver and bone marrow pathology

Eighteen liver and seven bone marrow biopsies from 44 patients with clinically and serologically proven Q-fever seen during a recent outbreak were studied. Highly distinctive fibrin-ring granulomas were found in seven liver and four bone marrow specimens. Lipid or nonspecific granulomas often containing neutrophils and variable numbers of giant cells were noted in 13 livers and seven bone marrows. A wide variety of nongranulomatous histological changes, frequently including steatosis and nonspecific "reactive" hepatitis, were seen in the liver biopsies. Identifiable rickettsiae were not present in tissue sections studied by microbiologic stains or electron microscopy. The histological response pattern to Coxiella infection is varied, and Q-fever should always enter the differential diagnosis of a granulomatous disease encountered in liver and bone marrow specimens.

Epithelioid hemangioma of the penis. A rare and distinctive vascular lesion

Two patients, aged 36 and 47 years, respectively, had indurated subcutaneous penile nodules that were treated by local excision. Histologically, the lesions were characterized by cords and nests of plump epithelioid cells separated by a loose stroma containing numerous lymphocytes and eosinophils. Light microscopy identified definite vasoformative areas and solid regions with cytoplasmic vacuolization and nuclear atypia. Ultrastructural studies and immunohistochemical analysis for factor VIII-related antigen and Ulex europaeus agglutinin I demonstrated that the lesions were of endothelial origin. After excision of the nodules, the two patients are free of disease 5 1/2 and 6 1/2 years later, respectively. To our knowledge, a review of the literature produced only one similar case. These unusual vascular lesions, of undetermined cause, are proliferations of endothelial cells exhibiting an epithelioid structure that should be considered benign and treated locally.

DNA flow cytometry of thyroid neoplasms

Mechanically dispersed cell suspensions from 23 thyroid lesions were studied by acridine orange flow cytometry. Eight of 14 carcinomas (three papillary, two medullary, two Hürthle cell, and one follicular) manifested abnormal DNA indices ranging from 0.6 to 2.0. Six carcinomas (four papillary and two medullary) were diploid. Four patients having papillary carcinomas with diploid DNA content were young women whose clinical course of disease was indolent. Three papillary carcinomas with abnormal DNA content were found in older men with clinically aggressive disease. One benign adenomatoid nodule displayed a small population with a low-degree hyperdiploid stemline (DNA index = 1.1) with low proliferative activity. Differentiation between clinically indolent and aggressive carcinomas may be possible by nuclear DNA determination, but further work is needed to determine the importance of proliferative activity in thyroid carcinoma.

Radionuclide angiography and endomyocardial biopsy in the assessment of doxorubicin cardiotoxicity

Thirty-eight patients with a mean age of 53.2 years (19 to 75 years of age), who were receiving doxorubicin (D) for malignant disease, were studied in order to determine the relationship between functional and morphologic myocardial changes at different dose levels. Serial patient evaluations included physical examination, chest x-ray, electrocardiogram (ECG), endomyocardial biopsy (EMB), and rest-exercise gated nuclear angiography (GNA), at doses of D ranging from 144 to 954 mg/m2 (mean, 426 mg/m2). Physical examination, chest x-ray, and ECG proved to be insensitive predictors of D cardiotoxicity. Correlation of GNA and EMB in 31 patient evaluations, exclusive of known heart disease, did not reveal any false-positive angiograms, and all abnormal GNAs were associated with abnormal biopsies. Use of stress GNA uncovered six abnormal ventricles which could have been missed with a rest GNA alone. It has been suggested that: (1) GNA is a reliable monitor of D therapy; (2) an exercise study should be performed when the rest ejection fraction is normal, but is unnecessary when the rest EF is abnormal; (3) all patients with a resting ejection fraction of less than 45%, exclusive of other cardiac disease, should have D discontinued; and (4) endomyocardial biopsy is useful in assessing D cardiotoxicity in patients with other possible causes of an abnormal GNA.