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H Bonkhoff

Publications and source records attributed to H Bonkhoff.

62 records · Page 4Linked to original sources
PubMed1992

The 'female prostate': location, morphology, immunohistochemical characteristics and significance.

Using immunostaining for prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), we can demonstrate prostate-analogous periurethral glands (the 'female prostate') in 66.7% of 33 cases. Histomorphologically, these glands resemble strongly the male prostate glands before puberty. They remain immature throughout life from the fetal period up to advanced age obviously because of a lack of an androgenic stimulus. The glands have long ducts leading into the urethra. A proper stroma component is missing. The immunohistochemical behavior of these glands also corresponds widely to that of the male prostate glands before puberty. No indications can be found for a proper biological function.

Acid Phosphatase↗
PubMed1991

Relation of endocrine-paracrine cells to cell proliferation in normal, hyperplastic, and neoplastic human prostate.

The relative distribution pattern of the pan-endocrine marker Chromogranin A (Chr A) and the proliferation-associated Ki-67 antigen was investigated in 20 prospectively sampled prostatectomy specimens. In cryostat sections, the Chr A immunoreactivity showed evidence of endocrine differentiation in all 15 prostatic adenocarcinomas. Nine tumors displayed a weak, 5 a moderate, and 1 adenocarcinoma a strong endocrine differentiation. These findings highlight the importance of endocrine differentiation in prostate malignancy that histologically resembles ordinary adenocarcinomas. The simultaneous demonstration of Ki-67 and Chr A revealed that in normal, hyperplastic, and neoplastic prostate tissue Chr A-positive cells were preferentially situated in proximity to Ki-67-labeled cells. This relative distribution pattern of both markers may indicate that endocrine cells are involved in controlling cell proliferation through a paracrine hormonal mechanism. However, an obvious correlation was not found between the degree of endocrine differentiation and proliferative activity in prostatic adenocarcinomas. Furthermore, a coexpression of Ki-67 and Chr A in the same (tumor) cells was not observed suggesting that the endocrine phenotype is only expressed in the G0 phase of the cell cycle as well as in normal, hyperplastic, and neoplastic conditions.

Adenocarcinoma↗
PubMed1991

Basement membranes in fetal, adult normal, hyperplastic and neoplastic human prostate.

The distribution of the various basement membrane (BM) components (type IV collagen, laminin and heparan sulphate proteoglycan) was studied in fetal, adult normal, hyperplastic and neoplastic prostates in formalin- and ethanol-fixed paraffin-embedded specimens. Stromal, epithelial and neoplastic BMs expressed differential susceptibility to pepsin treatment, suggesting conformational differences in the expression of epitopes on BM proteins in distinct anatomical structures and various lesions of the human prostate. In fetal prostate the acinar BM was regular and continuous in contrast to normal adult prostate and various hyperplastic conditions where the acinar BM was locally thickened or unreactive to the anti-BM antibodies. The localization pattern of BM components in grade I and grade II phases of prostatic cancer did not differ essentially from those found in various hyperplastic lesions. Regardless of the histopathological grade of malignancy, prostatic carcinoma cells were surrounded by distinct pericellular and periacinar membranes which were present even at points of contact with the stroma. This suggests that stroma invasion is invariably associated with neoplastic BM formations. Immunohistochemical evidence of the stromal or epithelial origin of neoplastic BMs could not be found. However, the consistent extracellular distribution of neoplastic BM components in contact with the stroma indicates that the elaboration of BM material requires a stromal influence.

Adenocarcinoma↗
PubMed1990

Morphological and immunohistochemical investigations of the utriculus prostaticus from the fetal period up to adulthood.

We investigated the utriculus prostaticus from the fetal period up to adulthood in 148 prostates. During the second half of gestation the utriculus had a simple tubular or a cystic form and was lined with metaplastic squamous epithelium which showed immunohistochemical positivity for different keratins, carcinoembryonic antigen, and peanut agglutinin binding sites. After birth, alveolar outgrowths of the utriculus developed. After puberty, the utriculus had become a complicated and variable structure. The epithelium no longer differed from that of the prostate glands either morphologically or immunohistochemically. Within the epithelium numerous endocrine cells were found containing neuron-specific enolase, chromogranin, and serotonin. The utriculus and ejaculatory ducts were embedded in a fibrous stroma with, after birth, numerous plexus-like blood vessels. This fibrous zone was peripherally bordered by a layer of smooth muscle. There was no evidence for a function of the utriculus differing from that of the prostate glands. Since the epithelium of both structures is identical immunohistochemically, the epithelium of the sinus urogenitalis most likely particpates in the lining of the utriculus during embryogenesis.

Adolescent↗
PubMed1990

Squamous cell carcinoma of the prostate.

Eleven case of squamous cell carcinoma of the prostate have been divided into four groups according to their histological features and natural history: a pure squamous cell carcinoma of the prostate (one case); b common prostatic adenocarcinoma with malignant squamous component after oestrogen treatment (two); c urothelial carcinoma of the prostate with malignant squamous cell metaplasia (four); and d urothelial carcinoma of the urinary bladder with squamous cell metaplasia growing into the prostate (four). The squamous portions may spread to invade the fibromuscular stroma and grow in prostatic ducts. Necrosis of comedo type and inflammatory infiltrates appeared in a number of cases. The survival times of nine patients ranged from 1 to 17 months. Squamous components were shown by immunohistochemistry to contain various keratin types, carcino-embryonic antigen and peanut agglutinin binding sites. Whenever a squamous cell carcinoma in the prostate is diagnosed histologically various possibilities as to its origin should be considered.

Aged↗
PubMed1989

Immunohistochemical analysis of the topographical relationship between the estrogen- and progesterone receptor in five human breast cancers. A simultaneous demonstration of both nuclear receptors in the same section by using a computer-assisted image processing.

A technique is described which allows precise assessment of the topographical relationship between the estrogen receptor (ER) and the progesterone receptor (PR) in the same histological section. It is based on the analysis of the results of immunohistochemical double staining by computer-assisted image processing. Five human ductal breast cancers were examined. The simultaneous demonstration of both receptors consists in the following principal steps: The primary antisera against the ER (monoclonal rat antibody) and the PR (monoclonal mouse antibody) are incubated simultaneously, but only the anti-ER antibody is demonstrated in the first staining step by using a goat anti-rat antibody as the linking antibody and the PAP complex from the rat, both antisera from the ER-ICA kit. The result is stored as a digitized grey image ("1. object image"). Then the colored end product and the residual peroxidase activity of the PAP complex are removed. In the second staining sequence the anti-PR-antibody is demonstrated by using a rabbit anti-mouse antibody as the linking antibody and the PAP complex from the mouse. The result is exactly positioned and also stored as a digitized grey image ("2. object image"). Though antibodies raised in different species were used, cross-reactivity could not be avoided. Grey values generated by cross-reactivity between the different antibody systems are evaluated in negative controls and are eliminated in the object images. The remaining (specifically stained) structures of both object images are copied into a final image so that the topographical relationship of the ER and the PR becomes obvious. The results show that in the five carcinomas investigated three types of receptor-positive tumour cells can be distinguished: Cells which coexpress the ER and the PR (1), cells which express either the ER (2) or the PR (3). The number of tumour cells showing one of these expression patterns varies from tumour to tumour.

Breast Neoplasms↗
PubMedDate not supplied

[Solid-pseudopapillary tumor of the pancreas in a 9-year-old girl].

Solid-pseudopapillary tumor of the pancreas constitutes a very rare benign or low-grade malignant lesion occurring most commonly in young women and girls. It was first described by Frantz. Local infiltration, distant metastasis and recurrence are very rare. Until today, the histogenetic origin of the tumor cell remains to be elucidated. In 1996, solid-pseudopapillary tumor of the pancreas was introduced in the World Health Organization (WHO) classification of tumors of the exocrine pancreas. Our case report--like a recently published work by Lange et al.--intends to underline the significance of solid-pseudopapillary tumor in the differential diagnosis of a pancreatic mass.

Biomarkers, Tumor↗