96
EPITOMES-PATHOLOGY
EPITOMES-PATHOLOGY
Such evaluation underestimates the number of patients who will die of melanoma, in part because some nodes contain tumor cells that are not detectable on examination of hematoxylin- and eosin-stained sections, even when step sectioning is done. Immunohistochemistry with antibodies to S-100 protein or monoclonal antibodies to melanoma-associated epitopes showed that a conventional histologic assessment underestimates the number of tumor-containing nodes by 29 % in patients with nodal spread of melanoma. A surprising 10% of patients with clinical stage I melanoma are in fact stage II when the nodes are examined by standard histologic techniques. A subsequent immunohistochemical assessment of patients whose nodes are negative on hematoxylin- and eosin-stained sections identifies 14% as having small occult micrometastases of melanoma in their nodes. The frequency of occult tumor cells increases with increasing thickness and depth of the primary tumor. Patients whose nodes contain micrometastases have a less favorable prognosis than those whose nodes are truly tumor free. Studies with dye injected intraoperatively into the area of the primary tumor have shown that nodes that contain micrometastases lie nearest to the primary tumor on the direct lymphatic drainage pathway from it. Most patients have occult tumor cells in a single node, but as many as three nodes may be involved. The capacity to identify metastastic melanoma at a truly early stage and to delineate precisely the nodes most likely to contain micrometastases provides a new approach to the management of high-risk stage I melanoma. By using the dye-orientation approach, it is possible accurately to stage such tumors by selective lymph node biopsy and to limit the use of lymphadenectomy to persons with proven nodal tumor. This technique spares node-negative patients the complications of lymphadenectomy. The immunohistochemical detection of micrometastases of melanoma will likely have important implications for staging, prognostication, and patient management. For these reasons immunohistochemical evaluation of lymph nodes is likely to become more widely applied. To validate the technique in the management of melanoma, a multicenter prospective trial is currently being organized. This management approach is unlikely to be limited to melanoma as occult tumor cells have been detected in patients with other forms of malignancy, including lung cancer, breast cancer, neuroblastoma, and vulvar cancer. ALISTAIR J. COCHRAN, MD Los Angeles, California
REFERENCES Cochran AJ, Lana AM, Wen DR: Histomorphometry in the assessment of prognosis in stage II malignant melanoma. Am J Surg Pathol 1989; 13:600-604 Cochran AJ, Wen DR, Morton DL: Occult tumor cells in the lymph nodes of patients with pathological stage I melanoma-An immunohistological study. Am J Surg Pathol 1988; 12:612-618 Morton DL, Cagle L, Wong L, et al: Intraoperative Lymphatic Mapping and Selective Lymphadenectomy: Technical Details of a New Procedure for Clinical Stage I Melanoma. Proceedings of the annual meeting of the Society of Surgical Oncologists, Washington, DC, May 1990, p 200
Cytopathology-A Multiparameter Approach CYTOLOGY AND FINE-NEEDLE aspiration biopsy (FNAB) are enjoying wide acceptance in this country as screening modalities, for diagnosis, for staging known malignant tumors, for assessing response to therapy, and for determining the need for further procedures. While the overall efficacy of cyto-
logic and FNAB diagnosis when practiced by experienced professionals has been proved, histologic confirmation is advisable in many cases-such as the primary diagnosis of malignant lymphoma-before treatment is initiated. It is exciting to recognize that the application of ancillary studies including flow cytometry, immunocytochemistry, and image cytometry in cytology has now enhanced the accuracy of cytologic diagnosis and is contributing to the understanding of the biologic behavior of tumors. Flow cytometry and image cytometry are used to quantitatively measure a variety of cell features including cytoplasmic and nuclear antigens and DNA content. Flow cytometric analysis is well established in evaluating hematologic specimens in which blood cell phenotyping and the quantification of various cell subpopulations are indicated. This method also has been applied successfully to cytologic specimens such as effusions, bladder washings, bronchoalveolar lavage fluid, cerebrospinal fluid, and cell suspensions of lymph nodes and tumors prepared from FNAB. Cell characteristics are assessed in a flow-based system in which thousands of cells are passed singly in a fluid stream through the tip of a flow chamber where scattered light and fluorescent signals are measured. The identification and quantification of cell surface antigens are helpful in evaluating lymphoproliferative disorders including non-Hodgkin's lymphomas. For example, the flow cytometric documentation of light chain restriction in a B-lymphocyte population is considered confirmatory of malignant lymphoma. In cases in which the cytologic diagnosis of malignant lymphoma is straightforward, flow cytometry also is useful in characterizing the lymphoma as of T- or B-cell origin or perhaps as one lacking B- or T-cell markers, data that generally correlate with the prognosis. Flow cytometry also may be used for DNA analysis. Combining flow DNA analysis for aneuploidy with a traditional urinary cytologic examination in patients with bladder cancer has been shown to dramatically increase the sensitivity for malignancy. This is just one example of the efficacy of a combined approach to diagnosis. Immunocytochemistry as applied to cytologic smears and cytocentrifuge preparations may be used to assess cell antigens and hormone receptors. These studies may be done on direct smears, cytospins prepared from body fluids, and cytospins made from cell suspensions from lymph node and tumor FNABs. The use of immunoperoxidase techniques for cell surface marker studies has been extended to the identification of estrogen receptors in patients with breast cancer. Estrogen receptor immunocytochemical assay has been used successfully on cytologic smears prepared from FNAB. The method has been found to be highly sensitive and specific with good correlation with biochemical assays for estrogen receptor from the same tumor. Image cytometry is used to measure cell components such as cell size, nuclear size, and DNA content in a microscopic slide-based system. Image cytometry may be applied to direct smears or cytocentrifuge preparations that are appropriately processed to stabilize DNA before hydrolysis. Generally carcinomas with an aneuploid DNA pattern have been found to behave more aggressively than those in the diploid range. This is particularly true in prostatic, bladder, and ovarian carcinomas. Cytology now commands the use of an impressive array of ancillary studies that enhance cytomorphologic interpretation. While their use requires considerable experience, they
THE WESTERN JOURNAL OF MEDICINE
*
JANUARY 1991
*
154
*
represent a valuable adjunct to diagnosis in the practice of cytology. ROBERT W. ASTARITA, MD La Jolla, California
REFERENCES Johnson TS, Katz RL, Pershouse M: Flow cytometric applications in cytopathology. Anal Quant Cytol Histol 1988; 10:423-458
1
97 Masood S: Use of monoclonal antibody for assessment of estrogen receptor content in fine needle aspiration biopsy specimen from patients with breast cancer. Arch Pathol Lab Med 1989; 113:26-30 Sneige N, Dekmezian RH, Katz RL, et al: MoThologic and immunocytochemical evaluation of 220 fine needle aspirates of malignant lymphoma and lymphoid hyperplasia. Acta Cytol (Baltimore) 1990; 34:311-322 Wied GL, Bartels PH, Bibbo M, Dytch HE: Image analysis in quantitative cytopathology and histopathology. Hum Pathol 1989; 20:549-571
ADVISORY PANEL TO THE SECTION ON PATHOLOGY STEPHEN N. BAUER,
MD
Advisory Panel Chair CMA Scientific Board Representative Carmichael
R. EUGENE TOLLS, MD CMA Section Chair San Francisco
WILLIAM H. HARTMANN, MD CMA Section Secretary Long Beach REARDON C. WEST II, MD CMA Section Assistant Secretary San Jose
BRIAN S. BULL, MD Loma Linda University KLAUS G. BENSCH, MD Stanford University ROBERT D. CARDIFF, MD, PhD University of California, Davis YUTAKA KIKKAWA, MD University of California, Irvine
PASQUALE A. CANCILLA, MD
JAMES L. BENNINGTON, MD
University of California, Los Angeles
San Francisco
COLIN M. BLOOR, MD
WILLIAM J. SIEGEL, MD
University of California, San Diego DOROTHY F. BAINTON, MD University of California, San Francisco
San Jose
CLIVE R. TAYLOR, MD, PhD Section Editor University of Southern California
RICHARD P. HENKE,
MD
Long Beach
STEPHEN A. GELLER, MD Los Angeles SCarT R. MILLER Medical Student University of California, Irvine
EPITOMES-PATHOLOGY
EPITOMES-PATHOLOGY
Such evaluation underestimates the number of patients who will die of melanoma, in part because some nodes contain tumor cells that are not detectable on examination of hematoxylin- and eosin-stained sections, even when step sectioning is done. Immunohistochemistry with antibodies to S-100 protein or monoclonal antibodies to melanoma-associated epitopes showed that a conventional histologic assessment underestimates the number of tumor-containing nodes by 29 % in patients with nodal spread of melanoma. A surprising 10% of patients with clinical stage I melanoma are in fact stage II when the nodes are examined by standard histologic techniques. A subsequent immunohistochemical assessment of patients whose nodes are negative on hematoxylin- and eosin-stained sections identifies 14% as having small occult micrometastases of melanoma in their nodes. The frequency of occult tumor cells increases with increasing thickness and depth of the primary tumor. Patients whose nodes contain micrometastases have a less favorable prognosis than those whose nodes are truly tumor free. Studies with dye injected intraoperatively into the area of the primary tumor have shown that nodes that contain micrometastases lie nearest to the primary tumor on the direct lymphatic drainage pathway from it. Most patients have occult tumor cells in a single node, but as many as three nodes may be involved. The capacity to identify metastastic melanoma at a truly early stage and to delineate precisely the nodes most likely to contain micrometastases provides a new approach to the management of high-risk stage I melanoma. By using the dye-orientation approach, it is possible accurately to stage such tumors by selective lymph node biopsy and to limit the use of lymphadenectomy to persons with proven nodal tumor. This technique spares node-negative patients the complications of lymphadenectomy. The immunohistochemical detection of micrometastases of melanoma will likely have important implications for staging, prognostication, and patient management. For these reasons immunohistochemical evaluation of lymph nodes is likely to become more widely applied. To validate the technique in the management of melanoma, a multicenter prospective trial is currently being organized. This management approach is unlikely to be limited to melanoma as occult tumor cells have been detected in patients with other forms of malignancy, including lung cancer, breast cancer, neuroblastoma, and vulvar cancer. ALISTAIR J. COCHRAN, MD Los Angeles, California
REFERENCES Cochran AJ, Lana AM, Wen DR: Histomorphometry in the assessment of prognosis in stage II malignant melanoma. Am J Surg Pathol 1989; 13:600-604 Cochran AJ, Wen DR, Morton DL: Occult tumor cells in the lymph nodes of patients with pathological stage I melanoma-An immunohistological study. Am J Surg Pathol 1988; 12:612-618 Morton DL, Cagle L, Wong L, et al: Intraoperative Lymphatic Mapping and Selective Lymphadenectomy: Technical Details of a New Procedure for Clinical Stage I Melanoma. Proceedings of the annual meeting of the Society of Surgical Oncologists, Washington, DC, May 1990, p 200
Cytopathology-A Multiparameter Approach CYTOLOGY AND FINE-NEEDLE aspiration biopsy (FNAB) are enjoying wide acceptance in this country as screening modalities, for diagnosis, for staging known malignant tumors, for assessing response to therapy, and for determining the need for further procedures. While the overall efficacy of cyto-
logic and FNAB diagnosis when practiced by experienced professionals has been proved, histologic confirmation is advisable in many cases-such as the primary diagnosis of malignant lymphoma-before treatment is initiated. It is exciting to recognize that the application of ancillary studies including flow cytometry, immunocytochemistry, and image cytometry in cytology has now enhanced the accuracy of cytologic diagnosis and is contributing to the understanding of the biologic behavior of tumors. Flow cytometry and image cytometry are used to quantitatively measure a variety of cell features including cytoplasmic and nuclear antigens and DNA content. Flow cytometric analysis is well established in evaluating hematologic specimens in which blood cell phenotyping and the quantification of various cell subpopulations are indicated. This method also has been applied successfully to cytologic specimens such as effusions, bladder washings, bronchoalveolar lavage fluid, cerebrospinal fluid, and cell suspensions of lymph nodes and tumors prepared from FNAB. Cell characteristics are assessed in a flow-based system in which thousands of cells are passed singly in a fluid stream through the tip of a flow chamber where scattered light and fluorescent signals are measured. The identification and quantification of cell surface antigens are helpful in evaluating lymphoproliferative disorders including non-Hodgkin's lymphomas. For example, the flow cytometric documentation of light chain restriction in a B-lymphocyte population is considered confirmatory of malignant lymphoma. In cases in which the cytologic diagnosis of malignant lymphoma is straightforward, flow cytometry also is useful in characterizing the lymphoma as of T- or B-cell origin or perhaps as one lacking B- or T-cell markers, data that generally correlate with the prognosis. Flow cytometry also may be used for DNA analysis. Combining flow DNA analysis for aneuploidy with a traditional urinary cytologic examination in patients with bladder cancer has been shown to dramatically increase the sensitivity for malignancy. This is just one example of the efficacy of a combined approach to diagnosis. Immunocytochemistry as applied to cytologic smears and cytocentrifuge preparations may be used to assess cell antigens and hormone receptors. These studies may be done on direct smears, cytospins prepared from body fluids, and cytospins made from cell suspensions from lymph node and tumor FNABs. The use of immunoperoxidase techniques for cell surface marker studies has been extended to the identification of estrogen receptors in patients with breast cancer. Estrogen receptor immunocytochemical assay has been used successfully on cytologic smears prepared from FNAB. The method has been found to be highly sensitive and specific with good correlation with biochemical assays for estrogen receptor from the same tumor. Image cytometry is used to measure cell components such as cell size, nuclear size, and DNA content in a microscopic slide-based system. Image cytometry may be applied to direct smears or cytocentrifuge preparations that are appropriately processed to stabilize DNA before hydrolysis. Generally carcinomas with an aneuploid DNA pattern have been found to behave more aggressively than those in the diploid range. This is particularly true in prostatic, bladder, and ovarian carcinomas. Cytology now commands the use of an impressive array of ancillary studies that enhance cytomorphologic interpretation. While their use requires considerable experience, they
THE WESTERN JOURNAL OF MEDICINE
*
JANUARY 1991
*
154
*
represent a valuable adjunct to diagnosis in the practice of cytology. ROBERT W. ASTARITA, MD La Jolla, California
REFERENCES Johnson TS, Katz RL, Pershouse M: Flow cytometric applications in cytopathology. Anal Quant Cytol Histol 1988; 10:423-458
1
97 Masood S: Use of monoclonal antibody for assessment of estrogen receptor content in fine needle aspiration biopsy specimen from patients with breast cancer. Arch Pathol Lab Med 1989; 113:26-30 Sneige N, Dekmezian RH, Katz RL, et al: MoThologic and immunocytochemical evaluation of 220 fine needle aspirates of malignant lymphoma and lymphoid hyperplasia. Acta Cytol (Baltimore) 1990; 34:311-322 Wied GL, Bartels PH, Bibbo M, Dytch HE: Image analysis in quantitative cytopathology and histopathology. Hum Pathol 1989; 20:549-571
ADVISORY PANEL TO THE SECTION ON PATHOLOGY STEPHEN N. BAUER,
MD
Advisory Panel Chair CMA Scientific Board Representative Carmichael
R. EUGENE TOLLS, MD CMA Section Chair San Francisco
WILLIAM H. HARTMANN, MD CMA Section Secretary Long Beach REARDON C. WEST II, MD CMA Section Assistant Secretary San Jose
BRIAN S. BULL, MD Loma Linda University KLAUS G. BENSCH, MD Stanford University ROBERT D. CARDIFF, MD, PhD University of California, Davis YUTAKA KIKKAWA, MD University of California, Irvine
PASQUALE A. CANCILLA, MD
JAMES L. BENNINGTON, MD
University of California, Los Angeles
San Francisco
COLIN M. BLOOR, MD
WILLIAM J. SIEGEL, MD
University of California, San Diego DOROTHY F. BAINTON, MD University of California, San Francisco
San Jose
CLIVE R. TAYLOR, MD, PhD Section Editor University of Southern California
RICHARD P. HENKE,
MD
Long Beach
STEPHEN A. GELLER, MD Los Angeles SCarT R. MILLER Medical Student University of California, Irvine
