INSTITUTE OF PATHOLOGY


		The Institute of Pathology was founded as a practice on 1st April 1981 by Professor Klaus Richter who at that time was a university lecturer in Hannover. In 1983, the Institute moved to premises in Berliner Allee 48, where it is still located today. Within a few years, the clients of the Institute increasingly comprised hospitals, practitioners with surgical practices including day clinics and centers of surgery. As a result, the number of specimens for histological and cytological investigations per year increased continuously. In accordance with the general trend, the autopsy figures fell from about 180 in 1982 to about 25 in 1998. The main Institute building is in Berliner Allee 48 with an annexe in Berliner Allee 50. More than 50 salaried staff and about 15 part time employees work at the Institute. These comprise ten graduates, including five fully qualified pathologists and a pathology assistant undergoing further training.


		The investigation materials are mainly sent in to the Institute where numerous histological and cytological investigations are conducted. It has recourse to a broad spectrum of histochemical and cytochemical, immunohistological and immunocytological investigation methods. A specialty of the Institute is the use of various molecular pathological investigation techniques (DNA in-situ hybridization (DISH), fluorescence microscopic in-situ hybridization (FISH), hybrid capture method, polymerase chain reaction (PCR), genomic sequencing, determination of microsatellite instabilities etc.). DNA cytometry is used to determine the degree of ploidy in certain prostate carcinomas and tumors of other organs. It is carried out on gynecological and extragynecological smear preparations. Determining the degree of ploidy may be very important in establishing the prognosis, therapy planning and relapse prophylaxis in metaplastic (especially precancerous and neoplastic) lesions. Furthermore, the range of our work comprises all other areas of gynecological and extragynecological cytology.


		The Institute cooperates closely with numerous hospitals in Hannover and beyond. In addition, there is very intense collaboration with medical practitioners of almost all specialties (internal medicine including gastroenterology, oncology, hematology and surgery, gynecology, dermatopathology, maxillofacial surgery, dental medicine, urology, ENT, orthopedic surgery, general medicine, pulmonology) in Hannover and beyond. Furthermore, we work with many medical practitioners specializing in gastroenterology, oncology and oncohematology.* The staff of the Institute is actively involved in developing the program and the research projects** of the Hannover Oncological Working Group. In addition, the Institute cooperates with a large number of interdisciplinary oncological practitioners.

Die Aktivitäten des Instituts für Pathologie umfassen das gesamte Fachgebiet

The Institute of Pathology is competent in all the techniques used throughout the fields of cytology, histology, histochemistry, cytochemistry, immunohistology, immunocytology, molecular pathology or molecular biology and DNA cytometry.
The Institute is a member of the German Health Network (DGN). It is therefore possible to send encrypted investigation results per e-mail. If appropriate, they can also be sent exclusively by mail and/or by fax in addition. The Institute has a modern computer network that is serviced by Medos, Birkenweiherstrasse 9, D-63505 Langenselbold.

Institute of Pathology
Prof. Dr. K. Richter and Colleagues
Berliner Allee 48
30175 Hannover

Tel 0511/ 30 77 77
Fax 0511/ 32 30 41
E-Mail: info@pathologie-richter.de

Chamber affiliation:
Ärztekammer Niedersachsen
gesetzliche Berufsbezeichnung:
Arzt / Facharzt für Pathologie

To watch the licence to practise medicine
click on the pictures.

In recent years, work has chiefly concentrated on molecular biology, e.g. familial breast cancers (BRCA-1 and BRCA-2), microsatellite instabilities, infections with human papillomaviruses and their importance for the pathogenesis and etiology inter alia for anal carcinoma and anogenital condylomatous lesions. A further priority of scientific investigations comprises urine cytology using immunocyto-logical investigation techniques. The results have been presented at national and in particular international scientific congresses and meetings, some of which have been published (inter alia Munich, Hong Kong, Siena, Buenos Aires).

Latest publications :
1. Richter, K.
Anal carcinoma – condylomata acuminata – human papillomavirus
10th World Congress of Cervical Pathology and Colposcopy
Abstracts, Buenos Aires, 7th – 11th November 1999 (Argentina)

2. Richter, K., L. Richter and J. Meier zu Eissen
Anal carcinoma – condylomata acuminata – human papillomavirus
Proceedings »World Congress of the International Federation for Cervical Pathology and Colposcopy – IFCPC«
(Buenos Aires, Argentina, 7th – 11th November 1999)

Small Cell Cancer of the Anal Canal – Report of a Rare Tumor – Publikation
Andreas Meyer¹, Frank Bruns¹, Klaus Richter², Viktor Grünwald³ and Johann H. Karstens¹
(Department of ¹Radiation Oncology and ³Hematology, Hemostaseology and Oncology; Hannover Medical School, Hannover; ²Institute for Pathology, Berliner Allee 48, Hannover, Germany)
Small Cell Cancer of the Anal Canal – Report of a Rare Tumor
Anticancer Research 27:1047-1050 (2007)

Die laparoskopische Resektion von Magendivertikeln : zwei Fallberichte
A.H. Schiller¹, B. Roggendorf², S. Delker-Wegener¹, K. Richter² and A. Kuthe¹
(¹DRK-Krankenhaus Clementinenhaus, Abteilung für Allgemein- und Unfallchirurgie, Hannover; ²Institut für Pathologie, Neuropathologie und Molekularpathologie, Hannover)
Die laparoskopische Resektion von Magendivertikeln : zwei Fallberichte
Zentralbl Chir 2007; 132 : 251-255

Identification of biology-based breast cancer types with distinct predictive and prognostic features: role of steroid hormone and HER2 receptor expression in patients treated with neoadjuvant anthracycline/taxane-based chemotherapy
SilviaDarb-Esfahani1, SibylleLoibl2, BeritMMüller1, MarcRoller2, CarstenDenkert1, MartinaKomor2, KarstenSchlüns1, Jens UweBlohmer3, JanBudczies1, BerndGerber4, AureliaNoske1, Andreasdu Bois5, WilkoWeichert1, ChristianJackisch6, ManfredDietel1, KlausRichter7, ManfredKaufmann8 and Guntervon Minckwitz2
PDF Download

The Institute has a very efficient cytological laboratory with specially trained expert staff and cytology laboratory assistants using modern techniques.
About 30,000 to 35,000 gynecological and extragynecological investigations are completed each year at the Institute.

The extragynecological investigations comprise the cytology of centesis and exfoliative material from almost all specialties (for example internal medicine including hematology, gastroenterology, urology, gynecology, surgery, ENT, pulmonology, radiology etc.).

Immunocytological, DNA cytometric and molecular pathological investigations are available as supplementary methods.

Gynecological investigation preparations (smear preparations) should be fixed by the client. Further molecular pathological procedures can be carried out on cancer prevention smears or preventative and curative cytological smears without additional work for the gynecologist or the doctor taking the smear, e.g. detection of chlamydiae, human papillomaviruses (HPV), tubercle bacilli and acid-fast rods, DNA cytometric investigations of the degree of ploidy and further diagnostic problems concerning the pathology of infections.

Extragynecological investigation preparations only require air drying (no further fixation).

ZytogruppeIVb Cytological group IVb

Immunhistologische und immunzytologische Untersuchungen

Immunohistological and immunocytological investigations are performed in a special laboratory with modern equipment and experienced specialist staff. Two computer-controlled immunostainers and automatic staining appliances guarantee exact and reproducible procedures and very good investigation results. About 50 mostly monoclonal and polyclonal antibodies are constantly available. Further antibodies are ordered from the various suppliers depending on the clinical and morphological problems under consideration.

We conduct immunohistological investigations to test the specificity and sensitivity of the monoclonal antibody 486p/13 for the company Medac.


		The laboratory at the Institute is capable of high performance in both qualitative and quantitative terms. About 23 female staff (medical laboratory assistants, receptionist nurses) work in the laboratory which is equipped with very modern technical apparatus, e.g. various automatic staining and embedding units, automatic dehydration units, automatic cover-slip units, electronic rotation microtomes etc. Apart from hematoxylin-eosin staining, all conventional special stains including immunohistological investigation techniques (see immunohistology) are carried out. Each year, the Institute completes very many investigation contracts, i.e. a much larger number of section preparations are produced. The operation preparations, biopsies and excisions are dispatched to the laboratory in buffered 4% to 6% formalin or as native preparations. Rapid-section investigations require consignment of native surgical preparations, biopsies, excisions etc. All institutions which send in specimens are supplied with appropriate dispatch vessels, investigation forms and post-paid mailing bags. These are returned to us either by mail, courier or taxi. If possible, small-scale investigation specimens (e.g. biopsies and small excidates) are processed immediately so that the result can be communicated to the consigner on the same day. The results concerning pathological anatomical expertises or pathological anatomical findings are sent by fax, mail, by telephone and/or by e-mail. Transmission of findings by e-mail requires that the consigner institution is a participant in the German Health Network (DGN).

The Institute has conducted molecular pathological investigations since 1984 and was thus one of the first institutes of pathology in Hannover to offer such modern methods of investigation. Since then, further molecular pathological investigation methods have become established at the Institute. Their use depends on the clinical and morphological diagnostic problem. They are mostly employed in morphological stage diagnostics.

Molecular pathology investigations are not only supplementary methods, but are often the key to diagnosis.

They are used in tumor pathology, especially in lymphoma diagnostics (e.g. B and T cell lymphomas) and in the pathology of infections (HPV infections, tuberculosis, chlamydial infections, borreliosis, specific coli infections etc.).
These methods of investigation can be applied to virtually all human tissues and fluids: e.g. excidates, biopsies, large surgical preparations, smears, sputum, body cavity effusions such as pleural effusions and ascites, bronchoalveoloar lavage (BAL) etc.

The range of molecular pathological methods of investigation comprises inter alia
1. DNA in-situ hybridization (DISH)

2. Fluorescence microscopic in-situ hybridization (FISH)
e.g. the Her-2/neu gene in tissue or in nuclei of tumor cells, especially in mammary carcinomas, but also chiefly in further gynecological carcinomas and tumors (e.g. ovarian carcinomas, endometrial carcinomas etc.)

3. Polymerase chain reaction (PCR)

4. Single-strand conformation polymorphism (SSCP)

5. Sequencing Der Analyser im Einsatz.
Specific DNA sequences are determined with
the Perkin Elmer sequencer or the
Applied Biosystems 310 Genetic Analyser.

These investigations are used inter alia in the analysis of BRCA-1 and BRCA-2 and in investigations of microsatellite instabilities

6. Investigation of microsatellite instabilities (MSI)

MSI are investigated in analyses of hereditary nonpolypoid colon carcinoma (HNPCC). Immunohistological procedures with the antibodies hMLH1 and hMSH2 are applied prior to the investigations.
Biopsies and excidates of intestinal polyps as well as adenomas and carcinomas from patients under 45 years old (see also "Bethesda criteria") are investigated.
If tumor-free tissue is not available for reference investigations, 5 ml of EDTA blood are required.

Such methods of investigation can also be applied on tumor tissues of other organs (e.g. bladder tumors).

Three examples of molecular pathological investigations are a B cell lymphoma, tuberculosis, and analysis of a microsatellite instability:1. Detection of monoclonalities in paraffin-embedded tissue form B cell lymphoid profilationsThe rearrangement of the immunoglobulin heavy chain genes is investigated with PCR. Primers are used for the framework regions 2 (Fr2A) and 3 (Fr3A) which are segments in the variable region of these immunoglobulin chains. In identical rearrangements such as occur in B cell clones (i.e. in the presence of non-Hodgkin lymphomas), amplificates of the same length (from 240 to 280 bp in Fr2A and 60 to 160 bp in Fr3A) arise in PCR. These can be recognized as bands in the electrophoretic gel, whereas in a nonuniform population of B cells involved for example in chronic inflammatory processes, different rearrangements are present that can be manifested as »smear« in the electrophoretic gel.

Figure 1: Rearrangement with
primers for Fr3A

Lane M: molecular weight markers at
intervals of 20 bp
Lanes 3 and 4 (Fr3A): distinct bands corresponding to a malignant non-Hodgkin lymphoma; lanes 9 and 10 (Fr3A): positive controls of non-Hodgkin lymphoma; lanes 11
and 12 (Fr3A): negative controls.

2.Detection of Mycobacterium tuberculosis
by means of PCR:
In PCR, primers are used that are located within the insertion sequence IS6110. This is only present in mycobacteria of the tuberculosis complex (M. tuberculosis, M. bovis and M. africanum). A positive reaction is shown in the presence of an amplificate 123 bp long (see lanes 7 and 8: positive control from a M. tuberculosis culture; lanes 9 and 10: negative control).

3.Detection of micsatellite instabilities and loss of heterozygosity (LOH)
to detect hereditary predisposition to cancer in colorectal carcinomas

About 5% to 8% of colorectal carcinomas are hereditary nonpolypoid colorectal carcinomas (HNPCC) with dominant autosomal inheritance. In molecular terms, these may be caused by germ line mutations in mismatch repair genes (hMSH2, hMLH1, hMSH6, hPMS2). In a gene mutation, nucleotide mismatches can no longer be repaired. This can be demonstrated especially well in single repetitive DNA sequences (microsatellites). Such mismatches can be demonstrated as microsatellite instability (MSI) by means of PCR. Furthermore, a loss of heterozygosity can also ultimately occur in malignant tumors, i.e. loss of the normal allele at a heterozygotic gene locus. MSI and LOH detection are used as a method of screening for HNPCC.

MSI bei D5S346

Figure 1: MSI bei D5S346 (= microsatellite APC, a dinucleotide repeat).

The upper curve shows two alleles 70 bp and 80 bp long (labelled "APC") in "normal tissue". The lower curve shows two alleles 72 and 82 bp in length that are 2 bp longer in the tumor tissue, i.e. MSI is present.

LOH bei BAT 26 (ein Mononucleotidrepeat

Figure 2: LOH in BAT 26 (a mononucleotide repeat).

The upper curve shows two alleles 98 bp and 116 bp long (labelled »BAT 26«) in normal tissue. The lower curve (tumor tissue) also still shows two alleles of the same length, but the peak of the second allele is lowered almost to the baseline which indicates a loss of this second allele in the tissue.

DNA-zytometrische Untersuchungsmethoden im Institut für Pathologie Hannover

DNA cytometry techniques can provide additional information enabling biological characterization of various tumors that may inter alia provide crucial pointers for the tumor treatment strategy.

In particular, the method has become important in establishing treatment strategies for certain prostate carcinomas, in breast cancers and in gynecological cancer prevention.

Detection of DNA aneuploidy involves based on an interpretation of DNA stem cell lines according to Böcking et al. (1993) (p < 0.001; Kolmogorov-Smirnov test with DNA stem cell line outside 1.85(c) and 2.15(c)). Interpretation of the prognostic value of the DNA data is based on the degree of DNA malignancy according to Böcking and Auffermann (1983) which takes into consideration the variability of the DNA values around the normal diploid peak.

Computer-controlled instruments modelled on those of the company Leitz are used for investigations after cell separation and Feulgen staining. The results are evaluated with the software and in accordance with the recommendations
of Böcking.

Professor Richter is a member of the »Diagnostic Cytometry Working Group«.

Copy of a protocol with a DNA histogram Protokoll eines DNA-Histogramms eines aneuploiden Prostatakarzinoms
of an aneuploid prostate carcinoma:

Zertifiziert durch die Firma Ventana Medical System S. A.

The Institute of Pathology is certified by the company Ventana Medical
Systems S.A. to carry out fluorescence in-situ hybridizatioon (FISH) to detect
the Her-2/neu gene

Certificate of Training

Institut für Pathologie Prof. Dr. K. Richter und Kollegen

Institute of Pathology
Prof. Dr. K. Richter and Colleagues
Berliner Allee 48
30175 Hannover
Tel 0511/ 30 77 77
Fax 0511/ 32 30 41
E-Mail: info@pathologie-richter.de

If you need directions to find us,
click here.

All recitations/presentations are downloadable PDF-Files.
Click on the title to download. (In german language, otherwise stated)

Anal carcinoma/Condylomata acuminata/Human Papillomavirus
Report on the »10th World Congress of Cervical Pathology and Colposcopy« Buenos Aires, 7.-11.1999, Argentinien (english)

Pathologisch-anatomische Grundlagen der chronisch-entzündlichen Darmerkrankungen

Molekularpathologische HPV-Detektion Methodische und
differenzial-diagnostische Aspekte

UroVysion • Vortrag • Präsentation

Obstipation • Begleittext • Präsentation

Lymphome • Vortrag

Dünnschichtenzytologie • Vortrag

Charge-Association • Vortrag

Plazentopathien • Vortrag

Divertikulose-Divertikulitis • Vortrag • Präsentation

Molekularpathologie in der Pathologie. Vortrag Berlin 2008
• Präsentation • Vortrag

minimal invasive Diagnostik Screening B3 • Vortrag

Analfissuren - Was sieht der Pathologe? Vortrag München 2009
• Präsentation • Vortrag

Chronische Analfissuren - eine morphologische Analyse. Vortrag Hannover 2009
• Präsentation • Text (siehe Vortrag München 2009)

Interaktives Quiz zur Abklärung von Mikroverkalkungen, Hannover 2009
• Präsentation • Vortrag

Lobuläre Neoplasie (LN) von Frau Dr. Beate Richter, Hannover 2009
• Präsentation

All lectures are downloadable PDF-Files.
Click on the title to download.(In german language, otherwise stated)

1. Hämatologie-Einführung-Beispiele

2. Anämien-Klassifikation

3. Leukämien-Myelodysplasien-Myeloproliferative Erkrankungen