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Ektopien adrenokortikalen Gewebes sind sehr haufig in kleinstknotiger Form periadrenal nachweisbar, entsprechen akzessorischem Gewebe und stellen eine Normvariante dar. Weiter entfernte Ektopien sind im Bereich der inneren mannlichen wie weiblichen Genitale nachweisbar. Bei Zustanden starker chronischer Uberstimulationen werden sie hyperplastisch und konnen echte Tumoren vortauschen („adrenal rest tumors“). Echte autonome Tumoren aus ektopem Gewebe mit oder ohne Uberfunktionen sind selten. Ektopien adrenomedullaren Gewebes kommen fast nur in unmittelbarer Nachbarschaft des normalen Markes vor. Ektopien in der Nebenniere entsprechen fast ausschlieslich Schilddrusenparenchym. Eine ektope Hormonbildung entsteht fast nur aus Phaochromozytomen und betrifft grostenteils Adrenokortikotropin (ACTH), sodass sich ein Cushing-Syndrom entwickelt.

In order to clarify the mechanism by which prolactin-secreting adenomas reduce in size during treatment with dopamine agonists (DA), we studied altogether 18 chromophobe pituitary adenomas by carrying out light microscopical cell counting of necrobiotic alterations and necroses in photographs of semi-thin sections. Depending on hormonal activity and preoperative treatment of the patients 3 groups of adenomas were formed: 6 prolactin producing adenomas were treated with bromocriptine and lisuride (group 3). 8 cases remained preoperatively without medical treatment (group 2). For comparison, we studied 4 cases of clinically inactive pituitary adenomas (group 1). All adenomas were immunohistologically positive for prolactin. By classifying each tumor cell in one of four stages of necrotic alteration (stage 1: intact cell, stage 2: slightly condensed nucleus and shrunken cytoplasm, stage 3: necrotic cell with still visible nuclear membrane, stage 4: cell debris) we arrived at an index for necrobiotic alterations of the 18 adenomas. We found a significantly higher rate of cell necroses in DA-treated tumors compared with preoperatively untreated prolactinomas and inactive adenomas. Previous investigations in this field have revealed that a reduction in cell size may well cause the shrinkage of the prolactinomas after DA-therapy. The results presented in this paper indicate, however, that the role of necroses now needs to be given much closer attention as an additional factor.

A 53-year-old woman had noticed numerous papules on her trunk and proximal parts of the limbs. They had healed with a central scar surrounded by a reddish wall. Four months later she had to undergo laparotomy for ileus, resulting from a perforation in the region of the middle jejunum: it was excised and sutured over. At laparotomy white plaque-like lesions were noted on the serosa of both small and large intestine. Histological examination of the jejunal exudate and of a skin biopsy both demonstrated malignant atrophic papulosis (Kohlmeier-Degos' disease). Treatment with ticlopidine, a platelet-aggregation inhibitor (250 mg twice daily), was initiated and she has now been free of extracutaneous symptoms for 6 years.

Hypophysenadenome mussen sicher von den ihnen oft ahnlichen Meningeomen, Granularzelltumoren, Chordomen und Germinomen abgegrenzt werden. Die Subklassifikation der Adenome ist abhangig von den eingesetzten Methoden und v.a. notwendig bei intraoperativ ungewohnlichen Befunden oder unvollstandiger Resektion, wenn eine spezifizierte Nachbehandlung erforderlich wird. Besondere Strukturcharakteristika und nichtimmunhistologische Farbeverfahren dienen der Typisierung. Bei den monohormonalen Adenomen konnen STH-Zell-Adenome (gering granuliert oder dicht granuliert) von Prolaktinzelladenomen (meistens gering granuliert, selten dicht granuliert), ACTH-Zell-Adenome (gering oder dicht granuliert), TSH-Zell-Adenome und FSH/LH-Zell-Adenome unterschieden werden. Unter den bihormonalen Adenomen sind mammosomatotrope Adenome und STH-Prolaktinzelladenome, aber auch das azidophile Stammzelladenom abzugrenzen. Plurihormonale Adenome sind durch den Einsatz verbesserter Antikorper seltener geworden. Zu den endokrin inaktiven Adenomen gehoren Nullzelladenome, onkozytare Adenome und FSH/LH-Zell-Adenome. Adamantinose und papillare Kraniopharyngeome unterscheiden sich strukturell und klinisch. Bei stark regressiv veranderten adamantinosen Kraniopharyngeomen helfen Keratin-Immunfarbungen bei der Diagnose.

Eine 61 Jahre alte Frau war wegen eines tastbaren und radiologisch darstellbaren 22,0 cm durchmessenden Tumors der linken Brust mit einer Ablatio mammae behandelt worden. Es zeigten sich 2 getrennte, aber unmittelbar benachbarte maligne und metastasierte Tumoren: ein schlecht differenziertes Leiomyosarkom und ein gut differenziertes papillares Mammakarzinom. Letzteres hatte 4 axillare Lymphknotenmetastasen gesetzt. Drei Monate nach der Operation verstarb die Patientin. Die Sektion ergab eine ausgedehnte Metastasierung des Leiomyosarkoms in die Lungen, das Herz, die Leber, die linke Niere sowie beide Nebennieren und als Todesursache rezidivierende Pulmonalarterienthrombembolien. Leiomyosarkome sind zwar als Folge einer Brustdrusenbestrahlung wegen eines Mammakarzinoms beschrieben worden. Ein koinzidentes Auftreten beider Tumorarten ist unseres Wissens bislang aber nicht mitgeteilt worden.

Within a series of 22 irradiated GH-producing adenomas we studied by light microscopical and morphometrical means the grading of nuclear pleomorphism, the proportion of densely granulated cells, the number of mitoses, multinuclear cells, necrotic or necrobiotic cells, and the degree of fibrosis in comparison to non-irradiated tumours. By electronmicroscopical morphometry we investigated the changes in area, circumference, area percentage, and number of intracellular structures. The rate of necrobiotic cells and the grade of nuclear pleomorphism were significantly higher in the irradiated tumours. The fibrotic areas were larger. No differences were observed in the degree of granulation and the rate of multinuclear cells. Mitoses were found in only one tumour. Within the group of the well-differentiated adenomas the areas and circumferences of the nuclei, nucleoli, mitochondria, immature secretory granules, and secretory granules increased significantly. The area percentages of the nuclei, mitochondria, immature secretory granules, and secretory granules increased as well. The mitochondria, Golgi-fields, and the rough endoplasmatic reticulum decreased in number. The undifferentiated adenomas changed almost in the same significant way. To us most of these changes are a sign of irradiation damage. The enlargement of intracellular structures could be a sign of an increased rate of secretory activity.

Surgical specimens of 15 normal and 106 para-adenomous anterior pituitaries were studied immunocytochemically and in part electron microscopically for the presence of hyperplasia. GH cell hyperplasia was found in 13% of all normal pituitaries, in 6% of the cases with Prolactin secreting adenomas and in 9% of the cases with ACTH secreting adenomas. Prolactin cell hyperplasia occurred in nearly equal percentages (17-23%) in normal pituitaries and in areas adjacent to GH-, Prolactin- or ACTH-secreting adenomas or adjacent to inactive adenomas. Previous findings of relatively more frequent Prolactin cell hyperplasia occurring together with Prolactin producing adenomas have to be revised. Prolactin cell hyperplasia as a primary source of hyperprolactinemia is very rare and almost always occurs in conjunction with oncocytic adenomas. ACTH cell hyperplasia was found in 13% of the normal pituitaries, in 14% of the cases with Prolactin secreting adenomas, in 58% of the cases with ACTH producing adenomas and in 40% of the pituitaries with GH secreting adenomas. We have no explanation for the latter result. ACTH cell hyperplasia may be the primary cause of Cushing's disease (18% of all Cushing cases). Hyperplasia of TSH cells in normal pituitaries was rare (7%) and with the exception of Prolactin producing adenomas (22%) was not found near adenomas. Clinical-pathological correlations are discussed.

The ZAC gene encodes a new zinc-finger protein that concomitantly induces apoptosis and cell cycle arrest and localizes to chromosome 6q24-q25, a well-known hot spot related to cancer. ZAC is highly expressed in the anterior pituitary gland, and its ablation by antisense targeting promotes pituitary cell proliferation. Here we investigate ZAC status in pituitary tumors to evaluate its role in pituitary tumorigenesis. Interest ingly, a strong reduction or absence of ZAC mRNA and protein expres sion was detected in nonfunctioning pituitary adenomas, whereas in clin ically active pituitary neoplasias, the decrease in ZAC expression was variable. Loss of expression was not associated with a mutation of the ZAC gene. Our observations suggest that alternative mechanisms of gene inactivation and/or altered regulation of the ZAC gene occur in nonfunctioning pituitary adenomas.

The 2017 World Health Organization (WHO) classification proposes to type and subtype primary adenohypophyseal tumours according to their cell lineages with the aim to establish more uniform tumour groups. The definition of atypical adenoma was removed in favour of high-risk adenoma, and the assessment of proliferative activity and invasion was recommended to diagnose aggressive tumours. Recently, the International Pituitary Pathology Club proposed to replace adenoma with the term of pituitary neuroendocrine tumour (PitNET) to better reflect the similarities between adenohypophyseal and neuroendocrine tumours of other organs. The European Pituitary Pathology Group (EPPG) endorses this terminology and develops practical recommendations for standardised reports of PitNETs that are addressed to histo- and neuropathologists. This brief report presents the results of EPPG’s consensus for the reporting of PitNETs and proposes a diagnostic algorithm.

Pituitary neuroendocrine tumors (PitNETs) : nomenclature evolution, not clinical revolution