Detection of occult nodal metastases in patients with colorectal carcinoma

Abstract

Immunohistochemical study may be used for detecting micrometastases by their expression of tumor-associated antigens. In 48 specimens of colorectal cancer from 47 patients, 49 of 249 lymph nodes (median, five per patient; range, 2-11) examined by light microscopic study contained tumor deposits. Sections of all lymph nodes were also examined by immunohistochemical study for carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA) expression using the indirect immunoperoxidase staining method. All 49 lymph node metastases (100%) from 20 patients stained positively for CEA and 45 (92%) expressed EMA. Of the 200 lymph nodes without metastases on light microscopic examination, anti-CEA revealed a single micrometastasis in a patient staged as Dukes' B. No additional metastases were detected with anti-EMA. In this series of patients immunohistochemical study has, therefore, influenced the histologic staging in only one patient (2%) and thus does not offer a significant benefit over conventional histologic staging.

Significado prognóstico das micrometástases nos linfonodos do carcinoma colorretal: detecção imunoistoquímica com anticorpos anticitoqueratina AE1/AE3

“…O reestadiamento a partir da detecção do envolvimento micrometastático pode não ter implicações clíni-cas objetivas, uma vez que os resultados deste estudo, a exemplo dos de outros autores 1,5,13,[18][19][20] , revelaram ausên-cia de impacto negativo da presença de micrometástases na sobrevivência dos doentes submetidos à extirpação curativa do carcinoma colorretal. Por outro lado, outros investigadores sustentaram que a identificação de micrometástases linfonodais teria influência negativa na sobrevivência dos seus portadores 3,17,21 .…”

Prognostic significance of occult lymph node micrometastasis in gastric cancer: a histochemical and immunohistochemical study based on 1997 UICC TNM and 1998 JGCA classifications

“…Micrometastasis can be defined by a single malignant cell or a cluster of malignant cells inside lymph node not detected by routine techniques as H&E, but only detected by special techniques as histochemical and immunohistochemical staining 1,4,6,11,18,29,31,33,35,36,37,38 . There are others definitions for micrometastasis as malignant cells cluster smaller than 2 mm in diameter 32 , smaller than 0.5 mm 27 and 5 or less cells 15 , all of them with stromal reaction such as granulation or desmoplastic tissue.…”

“…These may be due at least in part to the presence of lymph node micrometastasis at the time of resection. Although it is not consensual, micrometastasis can be defined as one single cell or a cluster of malignant cells inside of the lymph node that are not visualized by routine methods, but only by special dies, as immunohistochemical AE1-AE3 techniqu es 1,4,6,11,18,29,33,35,36,38 . In order to clarify this issue we studied 28 patients prospectively, treated by radical surgery, minimum of 30 lymph nodes resected from D2 lymphadenectomy and 43 lymph nodes from modified D3 lymphadenectomy.…”

Clinicopathological value of immunohistochemical detection of occult involvement in pT3N0 gastric cancer

“…The accuracy of such staining might well be improved by examination of a large numbers of lymph nodes from each patient and of multiple sections of each node, as well as by using a panel of monoclonal antibodies against tumor-associated antigens. However, such procedure would not be practical for a routine histopathology service [9]. A sensitive supplementary tool, for use in addition to standard H&E staining, would be most useful for improvement of clinical diagnoses.…”

“…In theory, it seems unlikly that patients with no metastasis to lymph nodes would experience postoperative recurrence of the tumor and should benefit from surgical resection of large numbers of uninvolved lymph nodes. Recent advances in histochemical and molecular biological techniques now allow identification of so-called occult involvement of lymph nodes in cases of breast and colorectal cancers that is generally not detected after standard hematoxylin and eosin (H&E) staining [5][6][7][8][9][10]. In this study, we tried to determine the extent of such occult involvement in lymph nodes by immunostaining of cytokeratin with the CAM 5.2 monoclonal antibody.…”