Tot Colorectal Tumors

Atlas of Large Section Histopathology
1. Auflage 2005
ISBN: 978-3-13-257827-2
Verlag: Thieme
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 152 Seiten, ePub

Large-section histopathology widens your perspectives... Correct diagnosis and staging are essential in determining the appropriate therapy of colorectal carcinoma, one of the most common malignancies in America and Europe. As medical science continues to develop rapidly, histopathology remains an essential part of diagnosis in most malignant diseases. In this era of interdisciplinary medicine, the role of pathology has expanded to provide images that easily correlate with endoscopic, radiological, or operative findings. In this remarkable atlas, Tibor Tot presents colon pathology in large histological sections, with cross-sections of entire tumors in their anatomic environments and their circumferential surgical margins. These unique images form a guide to diagnosis, tumor typing and staging according to TNM criteria. They help to assess the completeness of a surgical excision and to understand the heterogeneity of colorectal carcinomas. Features: Cases illustrated in two-page spreads with clinical information, conventional histopathology, and large-section histology images enlarged to almost a full page. Pathology seen in the context of surrounding tissues The margins of malignant tumors visible in their entirety Schematic guides to interpretation of the large-section images Emphasis on diagnostic advantages of using large section technique Technical guidelines for obtaining large-section histopathology specimens This atlas is the result of seven years of studying almost 2,000 cases of colorectal carcinoma and other intestinal lesions and is highly recommended for pathologists, radiologists, surgeons, and oncologists alike.

Tibor Tot

Zielgruppe

Ärzte

Autoren/Hrsg.

Tot, Tibor

Fachgebiete

• Medizin | Veterinärmedizin Medizin | Public Health | Pharmazie | Zahnmedizin Medizinische Fachgebiete Pathologie, Cytopathologie, Histopathologie
• Medizin | Veterinärmedizin Medizin | Public Health | Pharmazie | Zahnmedizin Klinische und Innere Medizin Onkologie, Krebsforschung
• Medizin | Veterinärmedizin Medizin | Public Health | Pharmazie | Zahnmedizin Chirurgie Onkologische Chirurgie

Inhaltsverzeichnis

Introduction
1 Adenomas
2 Early Colorectal Cancer
3 Advanced Colorectal Cancer
4 Other Intestinal Neoplasms
5 Non-neoplastic Lesions
6 Technical Considerations

Leseproben

1 Adenomas

Case 1.1 Villous Adenoma of the Rectum

Patient data: 63-year-old woman presenting with rectal bleeding. Endoscopically, a large, broad-based, soft and exophytic tumor was seen in her rectum, diagnosed on preoperative biopsy as adenoma.

Surgical treatment: Rectosigmoidal resection, no preoperative irradiation.

Specimen: 35-cm-long rectosigmoideum with an 8×6-cm soft exophytic tumor, 3 cm from the distal margin.

Histopathologic diagnosis: Villous adenoma of the rectum with moderate dysplasia. No signs of severe dysplasia or invasion.

Follow-up: 81 months, without signs of disease recurrence.

Villous adenoma of the rectum is often a large non-pedunculated tumor, covering the rectal mucosa over an area of several centimeters. Endoscopic biopsies usually reach only the superficial part of the tumor, the delicate long villous structures covered by dysplastic epithelium. The large histologic section (Fig. 1.1) also demonstrates the intact lamina muscularis mucosae: no signs of invasion are present. It is easy to compare the structures of the normal bowel wall (indicated by the red arrow in the schematic image, Fig. 1.1d) to the structures of the adenoma (the left side of the image, green arrows in Fig. 1.1d). Adenomas exhibit a dysplastic epithelium. The transition from normal to dysplastic epithelium is illustrated in Figure 1.1a (corresponding to the area marked with a red rectangle in Fig. 1.1d). Figure 1.1b represents a microscopic image of the delicate villous structures of the adenoma (corresponding to the blue rectangle in Fig. 1.1d). Figure 1.1c is a magnified detail of Figure 1.1b, illustrating the moderately dysplastic epithelium of this adenoma exhibiting elongated, stratified and crowded cell nuclei and a reduced number of goblet cells.

Fig. 1.1a

Fig. 1.1b

Fig. 1.1c

Practical points

• Villous adenomas are usually non-pedunculated, soft tumors covering a large area of the surface of the bowel wall. Large histologic sections are needed to visualize the entire lesion in one transection.
• The large histologic section is an ideal tool for assessing and demonstrating invasive tumor foci in such a large lesion, as these can be easily missed during the macroscopic examination and sampling of standard small blocks.

Fig. 1.1 Large-section histology image of a villous adenoma of the rectum.

Fig. 1.1d Schematic guide to the morphologic details in the large section in Fig. 1.1.

Case 1.2 Villous Adenoma of the Rectum

Patient data: 84-year-old woman with intermittent rectal bleeding and a long history of recurrent adenomas in her rectum.

Surgical treatment: Rectosigmoidal resection, no preoperative irradiation.

Specimen: 33-cm-long rectosigmoideum with a 9-cm segment containing a circumferential exophytic tumor, 6 cm from the distal margin.

Histopathologic diagnosis: Villous adenoma of the rectum with low-grade, partly moderate dysplasia. No signs of invasion.

Follow-up: 6 months, without signs of disease recurrence.

The large section in Figure 1.2 demonstrates another case of villous adenoma, which covers the entire circumference of the inner surface of the rectum. No signs of invasion are seen. The architecture of villous adenomas is complex, as they consist of primary finger-like processes extending outward from the bowel wall and containing fibromuscular stroma (indicated with blue arrows in Fig. 1.2c). Secondary finger-like processes, consisting of loose fibrous stroma with delicate vasculature and a surface covered by dysplastic epithelium, cover these structures. Figure 1.2a, b illustrate the complexity of these structures (corresponding to the red rectangle in the schematic image, Fig. 1.2c).

Fig. 1.2a

Fig. 1.2b

Practical points

• Villous adenomas may cover large areas of the entire circumference of the bowel wall. Large histologic sections are needed to visualize the entire lesion in one transection.
• Large histologic sections are also an ideal tool for analyzing the subgross architecture of complex lesions like adenomas.

Fig. 1.2 Large-section histology image of a villous adenoma of the rectum.

Fig. 1.2c Schematic guide to the morphologic details in the large section in Fig. 1.2.

Case 1.3 Villous Adenoma of the Colon

Patient data: 55-year-old male examined for weight loss. Colonoscopy detected a polypoid lesion in the sigmoid colon, diagnosed as adenoma on preoperative biopsy.

Surgical treatment: Sigmoidal resection, no preoperative irradiation.

Specimen: 15-cm-long segment of the sigmoid colon containing a 3 × 3-cm exophytic tumor, 3 cm from the distal margin.

Histopathologic diagnosis: Villous adenoma with moderate dysplasia. No signs of invasion.

Follow-up: 31 months, no signs of disease recurrence. The patient developed prostate cancer 12months after the sigmoideum resection.

The large section (Fig. 1.3) in the present case contains a transection of a villous adenoma of the sigmoid colon with long villous structures (magnified in Fig. 1.3a; the corresponding area is indicated by the yellow rectangle in Fig. 1.3d). Structures from the mesocolon are also seen in the same large section: a lymph node (indicated by the green arrow in Fig. 1.3d and magnified in Fig. 1.3b) and mesenterial blood vessels (indicated by the red rectangle in Fig. 1.3d and magnified in Fig. 1.3c). The large sections regularly include structures from the mesocolon, which is advantageous when assessing the extent of tumor growth.

Fig. 1.3a

Fig. 1.3b

Fig. 1.3c

Practical points

• Large histologic sections include a continuous tissue containing a transection of the bowel wall, a transection of the pathologic lesion(s), and a part of the mesenterial/periintestinal tissue. This non-fragmented image allows assessment of the relation of the lesion(s) to the surrounding structures.
• Lymph nodes and vascular structures, together with the intestinal lesion(s), can easily be analyzed in the large sections.

Fig. 1.3 Large-section histology image of a villous adenoma of the sigmoid colon.

Fig. 1.3d Schematic guide to the morphologic details in the large section in Fig. 1.3.

Case 1.4 Mucinous Carcinoma of the Rectum That Developed in a Villous Adenoma

Patient data: 88-year-old woman presenting with rectal bleeding. Endoscopically, an exophytic lesion was seen in her rectum. The preoperative endoscopic biopsy contained exclusively structures of adenoma.

Surgical treatment: Rectosigmoidal resection, no preoperative irradiation.

Specimen: 20-cm-long rectosigmoideum with a 6 ×5-cm exophytic tumor, 5 cm from the distal margin.

Histopathologic diagnosis: Mucinous carcinoma, low grade, infiltrating in but not beyond the lamina muscularis propria, 23 lymph nodes without signs of metastasis, radical excision, mesorectal margin 20 mm.

TNM stage: I (T2N0M0), Dukes A.

Follow-up: 36 months, without signs of disease recurrence.

Mucinous carcinoma may develop in villous adenomas. The large histologic section in Figure 1.4 demonstrates not only the mucinous carcinoma (green-colored area in the schematic image, Fig. 1.4c), but also the structures of the rests of the adenoma (orange arrows) as well as their relation to the cancer. To obtain a representative endoscopic biopsy, one has to reach the invasive part of the tumor, which is partly covered by the villous structures of the adenoma. Figure 1.4a, a microscopic magnification of the area indicated by the white rectangle in Figure 1.4c, shows the interface of the villous adenoma and the mucinous carcinoma. The large section offers proper documentation of the level of tumor invasion and, at the same time, reliably demonstrates the circumferential margin, including the mesorectal surgical resection margin. The mesorectal resection margin is easily assessed and its distance to the deepest invasive tumor structures is easy to measure, as indicated by the red double arrow in Figure 1.4c. The deepest level of invasion is indicated by the yellow rectangle in Figure 1.4c and is microscopically magnified in Figure 1.4b. Note also the four small reactive lymph nodes in the fatty tissue (encircled in Fig. 1.4c).

Fig. 1.4a

Fig. 1.4b

Practical points

• In order to obtain a representative biopsy, the endoscopist has to reach the invasive cancer, which is often covered by the rests of the adenoma.
• Taken in the plane of the deepest invasion, the large histologic sections reliably document the level of tumor growth.
• Large histologic sections are an ideal tool for assessing and demonstrating the...

Über Autor(innen)

Tibor Tot