TO THE EDITOR:
We read "Polyethylene Debris in Lymph Nodes after a Total Hip Arthroplasty. A Report of Two Cases" (77-A: 772—776, May 1995), by Morawski et al., with much interest. The authors presented two cases of what pathologists call histiocytosis after hip replacement1,4, which were discovered during dissection of pelvic lymph nodes in association with a radical prostatectomy. These two cases are demonstrative of a relatively new and rare pathological aspect of what can be found during dissection of pelvic lymph nodes for any pelvic carcinoma (bladder, prostate, or uterus). First, we would like to point out the importance of informing the pathologist of the presence and nature of an arthroplasty before examination of the lymph nodes for a pelvic carcinoma or otherwise. In fact, the histiocytic aspect of the reaction may be confused with other types of sinus histiocytosis or with metastatic carcinoma (for example, some may be composed of cells with foamy cytoplasm). A misinterpretation of this type of abnormality, which is induced by wear debris, could be detrimental to the patient. Second, at our institution, we recently saw an unusual case of systemic foreign-body reaction that mimicked sarcoidosis histologically and was localized in the spleen, liver, and pelvic lymph nodes. The patient had had a unilateral total hip replacement with a titanium prosthesis eight years before, and the histological examination showed particles of titanium and polyethylene debris in all of these locations, as confirmed with inductively coupled plasma-mass spectrometry. All of these observations demonstrate, in addition to difficulties with clinical and histological diagnosis, problems related to the long-term follow-up and composition of prosthetic implants.
Michel Péoc'h, M.D.; Dominique Pasquier, M.D.; and Basile Pasquier, M.D.: Department of Pathology, Centre Hospitalier Universitaire de Grenoble, B.P. 217, 38043 Grenoble, Cedex 09, France
Dr. Morawski, Dr. Coutts, Dr. Handal, Dr. Luibel, Dr. Santore, and Dr. Ricci reply:
We appreciate the comments and concerns of Dr. Péoc'h et al. We agree that the histiocytic reaction in the lymph nodes of patients who have had an arthroplasty may produce some confusion, particularly when frozen sections of dissected pelvic lymph nodes are being examined for any pelvic carcinoma (bladder, prostate, or uterus).
As a matter of fact, in the case of our first patient, the pathologist asked the urologist over the intercom to the operative suite if this patient had had a hip arthroplasty, as the findings in the lymph node were somewhat reminiscent of those in resection specimens from patients who had had silicone injections in the breast or silicone implants with subsequent histiocytic reactions in the axillary lymph nodes. Knowledge of a previous arthroplasty is of the utmost importance to avoid an erroneous diagnosis of metastatic carcinoma in the pelvic lymph nodes.
Dr. Péoc'h et al. point out an unusual case that mimicked systemic sarcoidosis. The cases that we reported did not suggest sarcoidosis and, to the best of our knowledge, none of our patients have manifested this reaction. This type of unusual reaction, however, will be kept in mind as we continue to see patients who have prosthetic implants.
David R. Morawski, M.D.: Fox Valley Orthopaedic Associates, 2525 Kaneville Road, Geneva, Illinois 60134
Richard D. Coutts, M.D.; Edgar G. Handal, M.D.; Richard Santore, M.D.: Arthritis Surgery Center, 7920 Frost Street, Suite 200, San Diego, California 92123
Joseph Luibel, M.D.: Department of Pathology, Sharp Memorial Hospital, 7901 Frost Street, San Diego, California 92123
John L. Ricci, Ph.D.: Department of Engineering, Hospital for Joint Diseases, 301 East 17th Street, New York, N.Y. 10003