Novel AIP mutation in exon 6 causing acromegaly in a German family.

The most frequent genetic alteration of familial isolated growth hormone producing pituitary neuroendocrine tumors is a germline mutation of the aryl hydrocarbon receptor-interacting protein (AIP) gene. Various AIP mutations are already known; however, an AIP mutation in exon 6 (c.811_812del; p.Arg271Glyfs*16) has not been reported yet. Here, we report a German family with two identical twins who were both affected by acromegaly and carried the above-mentioned novel AIP mutation. The father was found to be an unaffected carrier, while the paternal aunt most likely suffered from acromegaly as well and died from metastatic colorectal cancer. Apart from reporting a novel AIP mutation, this study does not only highlight the different clinical and histological features of the AIP mutated growth hormone producing pituitary neuroendocrine tumors but also confirms the poor responsiveness of dopamine agonists in AIP mutated acromegaly. Furthermore, it highlights the increased mortality risk of comorbidities typically associated with acromegaly.

Typing of inflammatory lesions of the pituitary.

Inflammatory pituitary lesions account for 1.8% of all specimens from the German Pituitary Tumor Registry. They occure in 0.5% of the autoptical specimens and in 2.2% of the surgical cases. Women are significantly more often affected than men and are often younger when first diagnosed. In general, primary and secondary inflammation can be distinguished, with secondary types occurring more frequently (75.1%) than idiopathic inflammatory lesions (15.4%). In primary inflammation, the lymphocytic type is more common (88.5%) than the granulomatous type of hypophysitis (11.5%). The most common causes of secondary inflammation are Rathke's cleft cysts (48.6%), followed by tumors (17.4%) such as the craniopharyngioma (9.1%), adenoma (5.5%) or germinoma (2.0%). More causes are tumor-like lesions (7.1%) such as xanthogranuloma (3.5%) or Langerhans histiocytosis (3.5%), abscesses (5.5%), generalized infections (5.1%), spreaded inflammations (4.7%) and previous surgeries (4.0%). In 1.6% of all specimens the reason for the inflammation remains unclear. The described classification of hypophysitis is important for specific treatment planning after surgery.

[Tumors of the adrenal glands : Update]. / Tumoren der Nebenniere : Aktualisierter Überblick.

Nodular hyperplasias and adenomas are by far the most frequently resected tumors of the adrenal cortex followed by pheochromocytomas, which are either discovered incidentally or become conspicuous due to hormonal hypersecretions. Cortical nodes and adenomas are easy to diagnose using simple staining methods. Uncertain cortical carcinomas, pheochromocytomas and other tumors of the adrenal region require additional immunohistochemical staining methods. Determination of the dignity of tumors of the adrenal cortex necessitates at least the Weiss score (possibly in its modified form), for oncocytic tumors the Bisceglia score and for pediatric tumors the Wieneke score. The Ki-67 index must also be taken into consideration. For pheochromocytomas the PASS and the GAPP systeme are used.

[Ectopia of the pituitary]. / Ektopien der Hypophyse.

The adenohypophysis has a large intrasellar part and two small parts at the pituitary stalk and the pharynx. Near this extrasellar pituitary tissue, and also in sinus sphenoidalis and sinus cavernosus, ectopic pituitary adenomas can develop. They are indistinguishable in structure and function from usual intrasellar adenomas. The neurohypophysis can show dystopias within complex malformations. In so-called pituitary stalk interruption syndrome, a real ectopia of the neurohypophysis is found at the eminentia mediana of the hypothalamus. Ectopic tissue in the pituitary is extremely rare: foci of ganglionic cells were found in the neurohypophysis and adrenocortical tissue in the adenohypophysis. Focal squamous epithelia in the anterior pituitary are a common finding but they are rather metaplastic from parenchymal cells than ectopic tissue. Small foci of ectopic salivary gland tissue are not rare in the intermediate zone.

[Ectopia of the adrenal]. / Ektopien der Nebenniere.

Ectopia of nodular adrenocortical tissue is very frequently found in the periadrenal region. It corresponds to accessory adrenal tissue and is a normal variant. Ectopia in more distant regions are found in inner male or female genitalia. Strong long-lasting hyperstimultions induce hyperplasia and simulate true tumors ("adrenal rest tumors"). Real autonomic tumors from ectopic adrenal tissue with or without hyperfunction are rare. Ectopia of adrenomedullary tissue are nearly exclusively found in the surroundings of normal medulla. Ectopia in the adrenals corresponds almost exclusively with thyroid tissue. Ectopic secretion of hormones, mostly ACTH, can be found in pheochromocytomas and induces hyperfunction (Cushing's syndrome).

[Adrenalitis]. / Adrenalitis.

Inflammation of the adrenal glands is caused by autoimmunopathies or infections and can induce adrenal insufficiency. Autoimmune lymphocytic adrenalitis is often combined with other autoimmune diseases and the most frequent cause of Addison's disease; however, it only becomes clinically apparent when more than 90 % of the adrenal cortex has been destroyed. Histological features are characterized by lymphoplasmacytic inflammation leading to an increased destruction of adrenocortical tissue but less severe courses can also occur. The second most frequent form of adrenalitis is adrenal tuberculosis, showing typical granulomatous findings that are nearly always caused by spreading from a tuberculous pulmonary focus. Other bacterial as well as viral infections, such as Epstein-Barr virus (EBV), cytomegalovirus (CMV) and others, generally affect the adrenal glands only in patients with immunodeficiency disorders. In these infections, the adrenal cortex and medulla are frequently involved to roughly the same extent. Although surgical specimens from inflammatory adrenal lesions are extremely rare, the various forms of adrenalitis play an important role in the post-mortem examination of the adrenal glands for clarification of unclear causes of death (e.g. death during an Addisonian crisis).

[Hypophysitis : Types and differential diagnosis]. / Hypophysitis : Formen und Differenzialdiagnose.

Inflammatory findings in the pituitary glands account for approximately 1 % of operations in the sellar region. Primary inflammation (e.g. lymphocytic and idiopathic granulomatous hypophysitis) have to be differentiated from secondary types (e.g. concomittant inflammation with Rathke's cleft cysts, craniopharyngiomas and germinomas) and involvement of the pituitary in generalized inflammation (IgG4-related disease, sarcoidosis and septicopyemia). Langerhans cell histiocytosis also has to be considered for the differential diagnostics. Lymphocytic hypophysitis shows lymphocytic infiltrations of varying density, predominantly of the T­cell type. Granulomatous hypophysitis has the features of sarcoidosis and can only be diagnosed by exclusion of generalized sarcoidosis. Secondary hypophysitis has a mixed cell infiltration, especially by histiocytic infiltration and predominantly originates from ruptures or bleeding from Rathke's cleft cysts. The frequently very sparse remnants of cyst epithelium should be confirmed by pankeratin immunostaining.

[Grading of neuroendocrine tumors]. / Grading neuroendokriner Tumoren.

The current WHO classification of neuroendocrine tumors (NET) differentiates between typical carcinoids (low grade NET), atypical carcinoids (intermediate grade NET) and small cell and large cell carcinomas (high grade NET) according to the prognosis. Neuroendocrine neoplasms (NEN) of the gastrointestinal tract and the pancreas are graded in an identical way. Together with the TNM system this enables a preoperative estimation of the prognosis in biopsies and fine needle aspirates. Well-differentiated tumors are graded into G1 tumors by the number of mitoses, <2 per 10 high-power fields (HPF) and the Ki-67 (index <3 %) and G2 tumors (2-20 mitoses/10 HPF, Ki-67 3-20 %). Discrepancies between the number of mitoses and the Ki-67 index are not uncommon and in these cases the higher value of the two should be applied. The more differentiated tumors of the G3 type have to be differentiated from undifferentiated carcinomas of the small cell type and large cell type with a much poorer prognosis. Prognosis relevant grading of thyroid cancers is achieved by special subtyping so that the G1-G3 system is not applicable. The rare cancers of the parathyroid gland and of the pituitary gland are not graded. Adrenal tumors also have no grading system. The prognosis is dependent on the Ki-67 index and with some reservations on the established scoring systems.

[Fine-needle aspiration (FNA) of the thyroid gland : Analysis of discrepancies between cytological and histological diagnoses]. / Feinnadelaspiration (FNA) der Schilddrüse : Analyse diskrepanter zytologischer und histologischer Diagnosen.

BACKGROUND: Diagnostic problems of thyroid cytology are frequently discussed, but relevance and causes of discrepant cytological and histological diagnoses are rarely studied in detail. OBJECTIVES: Investigation of causes and relevance of discrepant diagnoses. MATERIALS AND METHOD: The analysis includes 297 patients who had thyroid resection after prior fine needle aspiration (FNA) and is based on the cytological and histological reports. In special cases, cytological and histological specimens were re-examined. RESULTS: Malignant tumors were found in 45 patients (15.1 %). In 5 patients the cytological diagnosis was "false negative". Three of these 5 tumors were papillary carcinomas (PTC) of ≤10 mm, one an obviously nonmalignant papillary proliferation of the thyroidal epithelium and one a malignant lymphoma complicating autoimmune thyreoiditis (AIT). In 11 of the 35 patients with a FNA diagnosis "suspicious of malignancy" or "malignant," 1 AIT, 4 goiter nodules, and 6 adenomas were diagnosed histologically. However, since distinct nuclear atypia was found in three of five false positive diagnoses, there still remains doubt in their benignity. CONCLUSIONS: Carcinomas of ≤10 mm incidentally detected in the resected thyroid tissue may not be relevant to the patient and do not reduce the high negative predictive value of FNA. The final diagnosis on the resected tissue should include the cytological findings. Discrepant findings should be commented in the report to the clinician.

[New aspects of tumor pathology of the pituitary]. / Neues aus der Tumorpathologie der Hypophyse.

Pituitary adenomas have to be studied in detail for structural characteristics, especially regarding the degree of granulation and immunohistochemical hormone expression, such as growth hormone (GH), prolactin, adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), luteinizing hormone (LH) and proliferation markers (e.g. Ki-67 and p53) for correlation to clinical data and assessment of the prognosis. If histological and immunostaining data do not correlate to the patient data, explanations for the discrepancies must be found. All active adenoma types can also be present as inactive, so-called silent adenomas showing the same features. An increased Ki-67 index (> 3%), significant nuclear expression of protein p53 and mitoses are characteristic of atypical adenomas. Up to now the biological relevance of these atypical adenomas, especially their role as preneoplasms for pituitary carcinomas has not been fully elucidated. The only proof of a pituitary carcinoma is the existence of metastases. Extensive local invasion and a greatly increased Ki-67 index are not sufficient for this diagnosis. Craniopharyngiomas have to be classified into adamantinomatous types (intrasellar and suprasellar) and papillary types (only suprasellar). Regressive changes are found in adamantinomatous types only. Strong regression may lead to difficulties in the differential diagnosis of Rathke's cleft cysts with squamous metaplasia. Demonstration of nuclear expression of beta-catenin in these cases enables the diagnosis of craniopharyngioma. Papillary craniopharyngiomas are characterized by BRAF mutations that may be helpful in the differential diagnosis. All pituicytomas of the neurohypophysis, all spindle cell oncocytomas of the anterior pituitary and all granular cell tumors of the posterior pituitary express thyroid transcription factor 1 (TTF-1) and are thought to be variants of a common uniform spindle cell tumor of the pituitary.

[New aspects of tumor pathology of the adrenal glands]. / Neues aus der Tumorpathologie der Nebenniere.

In daily routine pathology of the adrenal glands three tumor entities are important: adrenocortical tumors, adrenomedullary tumors and metastases. The differentiation of these three main tumor types can often be difficult structurally but immunostaining enables a definite diagnosis in nearly all cases. Adrenocortical tumors are positive for steroidogenic factor 1 and melan-A and always negative for chromogranin A whereas adrenomedullary tumors express chromogranin A but never keratin. A broad spectrum of antibodies is available for the identification of metastases and even the rare epithelioid angiosarcomas. For adrenocortical tumors, adenomas and carcinomas can be differentiated using three scoring systems and the Ki-67 index in adenomas should not exceed 3%. Using scoring systems and the Ki-67 index approximately 90% of cortical tumors can be differentiated into benign or malignant tumors. For pheochromocytomas two scoring systems are used for differentiating benign and malignant tumors but the results are less dependable.

[Hereditary cardiac amyloidosis with transthyretin mutations. A cause of sudden death ]. / Hereditäre kardiale Amyloidosen mit Mutationen des Transthyretin. Ursache des plötzlichen Todes.

Hereditary amyloidoses present a clinically and genetically heterogeneous group of autosomal dominant diseases. The most frequent form is associated with mutations of the transthyretin gene. The type of mutation determines the process, the organs primarily involved as well as the time of onset of the disease. Life expectancy is generally limited by the degree of cardiomyopathy. The cases of two male patients who died suddenly and unexpectedly are presented. In both cases, autopsy revealed a biventricular cardiac hypertrophy. Cardiac amyloidosis was diagnosed by means of histologic and genetic analysis. Early diagnosis is essential for those affected, since liver transplantation still represents the only effective treatment. This illustrates the benefit of autopsy investigations for surviving relatives, who may themselves be affected by the disease.

Adrenal cancer: relevance of different grading systems and subtypes.

PURPOSE: The subclassification of adrenal cancers according to the WHO classification in ordinary, myxoid, oncocytic, and sarcomatoid as well as pediatric types is well established, but the criteria for each subtype are not sufficiently determined and the relative frequency of the different types of adrenal cancers has not been studied in large cohorts. Therefore, our large collection of surgically removed adrenal cancers should be reviewed o establish the criteria for the subtypes and to find out the frequency of the various types. METHODS: In our series of 521 adrenal cancers the scoring systems of Weiss et al., Hough et al., van Slooten et al. and the new Helsinki score system were used for the ordinary type of cancer (97% of our series) and the myxoid type (0.8%). For oncocytic carcinomas (2%), the scoring system of Bisceglia et al. was applied. RESULTS: Discrepancies between benign and malignant diagnoses from the first thee classical scoring systems are not rare (22% in our series) and could be resolved by the Helsinki score especially by Ki-67 index (more than 8% unequivocally malignant). Since all our cancer cases are positive in the Helsinki score, this system can replace the three elder systems. For identification of sarcomatoid cancer as rarest type in our series (0.2%), the scoring systems are not practical but additional immunostainings used for soft tissue tumors and in special cases molecular pathology are necessary to differentiate these cancers from adrenal sarcomas. According to the relative frequencies of the different subtypes of adrenal cancers the main type is the far most frequent (97%) followed by the oncocytic type (2%), the myxoid type (0.8%) and the very rare sarcomatoid type (0.2%). CONCLUSIONS: The Helsinki score is the best for differentiating adrenal carcinomas of the main, the oncocytic, and the myxoid type in routine work. Additional scoring systems for these carcinomas are generally not any longer necessary. Signs of proliferation (mitoses and Ki-67 index) and necroses are the most important criteria for diagnosis of malignancy.

Expression of ghrelin and its receptor in human tissues.

Ghrelin is a peptide thought to be involved in the regulation of appetite. Furthermore, significant effects on the release of growth hormone (GH) and ACTH were demonstrated. Contributing to the physiological relevance of this hormone, we investigated the expression of ghrelin and its receptor (GHS-R) in several normal human tissues. RNA samples (BD Biosciences) underwent one-step TaqMan Real-Time RT-PCR. Immunohistochemistry was performed on paraffin-embedded tissues using specific primary antibodies against ghrelin and its receptor. Relevant ghrelin mRNA levels were detected in all human tissues with the highest levels in stomach, pituitary, and small intestine. By immunohistochemistry, ghrelin peptide expression was detectable in reproductive and endocrine organs (ovary, anterior pituitary, adrenal gland), and organs of the gastrointestinal tract (stomach, pancreas). GHS-R1a mRNA expression was demonstrated in 10 of 24 human organs analyzed with the highest levels in pituitary, adrenal gland, and spinal cord. Expression of the receptor peptide was detected by immunohistochemistry in endocrine and reproductive organs (anterior pituitary, thyroid, pancreas, testis), parts of the CNS (cerebrum, cerebellum), and in single cells of bone marrow. Expression of both ghrelin and its receptor in endocrine and reproductive organs may indicate new endocrine or paracrine mechanisms of regulation in these tissues.

[Acromegaly-associated lesions of the nasal mucosa. Case report]. / Mit Akromegalie assoziierte Veränderungen der Nasenschleimhäute. Fallbericht.

Acromegaly is a rare disease caused by a growth-hormone-secreting pituitary adenoma. Symptoms include enlargement of the hands, feet, and jaw with growing dental interspaces, as well as hypertrophy of the tongue and nasal and sinusoidal mucosa. The two latter symptoms are mostly responsible for the accompanying obstructive sleep apnea syndrome. Besides these "cosmetic" symptoms, the disease is associated with hypertension and diabetes mellitus, as well as with an increased risk for adenomas and carcinomas of the colon. The average time span from first symptom to diagnosis is well over 6 years; a single determination of insulin-like growth factor 1 in serum can confirm the disease. The treatment of choice remains surgical resection of the adenoma in suitable patients, whereas in extensive disease with invasion of surrounding tissue, drug therapy and/or radiotherapy may be necessary.

A standardised diagnostic approach to pituitary neuroendocrine tumours (PitNETs): a European Pituitary Pathology Group (EPPG) proposal.

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.

Expression of the zinc-finger transcription factor Snail in adrenocortical carcinoma is associated with decreased survival.

In this study, we evaluate whether Snail is expressed in adrenocortical cancer (ACC) and if its expression is related to patient outcome. One of the best known functions of the zinc-finger transcription factor Snail is to induce epithelial-to-mesenchymal transition (EMT). Increasing evidence suggests that EMT plays a pivotal role in tumour progression and metastatic spread. Snail and E-cadherin expression were assessed by immunohistochemistry in 26 resected ACCs and real-time quantitative RT-PCR expression analysis was performed. Data were correlated with clinical outcome and in particular with overall patient survival. Seventeen of 26 (65%) ACC tumour samples expressed Snail when assessed by immunohistochemistry. Snail expression was neither detected in normal adrenocortical tissue, nor in benign adrenocortical adenomas. Expression levels were confirmed on the mRNA level by Real-Time-PCR. Survival rates were significantly decreased in Snail-positive tumours compared to Snail-negative tumours: 10 out of 16 vs one out of eight patients succumbed to disease after a median follow up of 14.5 and 28.5 months, respectively (P=0.03). Patients with Snail-expressing ACCs presented in advanced disease (11 out of 12 vs 6 out of 14, P=0.01) and tend to develop distant metastases more frequently than patients with negative staining (7 out of 11 vs two out of eight, P=0.19). In conclusion, we describe for the first time that Snail is expressed in a large subset of ACCs. Furthermore, Snail expression is associated with decreased survival, advanced disease and higher risk of developing distant metastases.