A United States Army Medical Department continuing education program, the 24 th annual Armed Forces seminar on obstetrics and gynecology, microinvasive carcinoma of the cervix with Milton H Lehman, junior, Lieutenant colonel MC, United States Army OBGYN Department, Walter Reed Army Medical Center, Washington DC. The histologic features of intraepithelial carcinoma of the cervix have been well described. Little controversy exists when the disease is limited to the surface epithelium. However, there is no general agreement concerning the definition or appropriate therapy for microinvasive carcinoma of the cervix. Recent reviews have noted the vague and variable definition of the term microinvasive carcinoma and the exclusion. In some reports of confluent patterns or cases with vascular involvement. Therapeutic results are difficult to assess because of the variability in the definition of the disease. In order to gain additional information concerning several diagnostic and prognostic variables. All cases of microinvasive carcinoma treated at Walter Reed Army Medical Center between September 1, 1961 and January 1, 1975 were reviewed. 56 cases were diagnosed as microinvasive carcinoma. The first slide please, micro invasion was defined in this review as stromal penetration by carcinoma not exceeding a depth of five millimeters from the surface at the apparent point of origin measurement was made from the surface since the epithelial stromal junction was frequently obscured by the invading tumor. As is a parent in this line cases were not excluded for apparent lymphatic invasion or for confluent growth pattern. Next line, 51 cases met the criteria for micro invasion and formed the basis for this report. 47 patients underwent complete radical hysterectomy and pelvic lymphadenectomy. One had a radical vaginal shout a hysterectomy. One had extrafascial abdominal hysterectomy with upper carpectomy and two had radical abdominal hysterectomies without lymphadenectomy. Next line. Yeah, there were 20 recorded complications. However, only the six shown here were considered to be major since each resulted in prolongation of hospital stay or permanent disability. A rate of 11.8%. There were no deaths associated with the treatment and no vesical vaginal or ureteral vaginal file. Next line, the mean age of the patients was 36.94 years which is somewhat lower than the mean age quoted in another series. The main parity was 3.04. There was one nips patient and nonu gravitas. One patient aged 63 was post menopausal pap smear has taken their routine gynecologic examinations in essentially asymptomatic patients led to the diagnosis in 32 or 62.7%. Symptoms of abnormal bleeding prompted medical consultation and led to the diagnosis in 19. Next line in reviewing the cone biopsies. The histologic features evaluated were depth of invasion, differentiation of malignant cells at the site of invasion. Apparent lymphatic or capillary like space cl space invasion pattern of invasion, whether finger like or confluent degree of inflammation and presence of disease at the margin of the cone biopsies. The hysterectomy specimens were evaluated for the presence of residual disease, metastases and number of nodes removed next line. The follow up of patients in this series has been 100% to within 14 months of the preparation of this report. The the five year survival is 100%. 8 of the nine patients followed for more than 10 years are living and well, one patient died of pneumonia. Eight years post operatively with no evidence of tumor at post mortem examination. There were two patients who were found to have second primary malignancies. Next line space invasion was considered to be present if tumor cells were found in a space lined by flattened endothelial type cells, serial or step sections were not done in searching for cl space invasion. Next line, cl space involvement was seen in 12 or 24% of the cases. No cl space invasion occurred in those tumors invading up to one millimeter while 26% of those invading 1.1 to 3 millimeters and 43% of those invading 3.1 to 5 millimeters had cl space invasion. Next line regardless of the depth of invasion. Tumors showed cellular differentiation at the invading margins with the same frequency, these cells appeared larger with more eosinophilic cytoplasm than those of carcinoma cy two. In the other part of the slide. Next line, the determination of growth pattern proved to be difficult and somewhat arbitrary. Since tumors sometimes contain both patterns. As is demonstrated here, the finger like pattern and the confluent pattern. When that occurred, the predominant pattern was a sign. In one case, a determination could not be made due to the small size of the lesion of the remaining 50. The pattern was judged to be finger like in 37 and confluent in 13 microinvasive carcinoma extended to the margins of the cone. In 23 of the 47 cases diagnosed by conation margin involvement was statistically unrelated to the depth of invasion, presence of border differentiation, presence of cl space invasion or pattern of invasion. In the 49 hysterectomy specimens reviewed residual microinvasive disease was present in seven that had been preceded by colonization and in two, that had been preceded by punch biopsy. One additional case, next line, one additional case demonstrated by this slide showed residual invasive disease to a depth of eight millimeters when the cone had shown invasion to a depth of only 2.5 millimeters. Thus, nine of the 47 patients having conization had residual invasive disease in their hysterectomy specimens. All these had micro invasive disease involving the cone margins, finger like patterns were associated with residual disease in 27% of cases. But confluent patterns had no associated residual disease of the 23 with the involvement of the cone margin. 39% had residual invasive disease. However, none of the 24 with clear margins had residual invasion. Next line. When correlating the histologic features with each other, statistically significant associations were found between depth of invasion and cl space involvement pattern of invasion and residual invasive disease and presence of micro invasion, micro invasion at the cone margin and residual invasive disease slide off the association between the depth of invasion and cl space involvement appears to be of little significance clinically since neither feature is correlated with not metastasis or residual disease. Although the incidence of note metastasis in the presence of cl space invasion has been reported to occur in two of 10 patients. Roach and Norris found that the incidence of cl space invasion varied according to whether or not step sections were examined. 24% of the patients in our series demonstrated cl space invasion when step sections were not done and no, not metastases were encountered in 2600 lymph nodes examined the association between the presence of microinvasive disease at the cone margin and the presence of residual invasive disease is expected. However, the high incidence of cone margin involvement in our series is surprising. No residual invasive disease was found when the cone margins were clear, but residual invasion was present in 39% of cases when the cone margins were involved. Margin involvement may occur more frequently in microinvasive disease than in carcinoma in C two because micro invasion often occurs higher in the endocervical canal. Frequently, the pathology reports did not indicate whether the margin was involved. This information should routinely be reported by the pathologist. If it is not, the clinician is obligated to request this information in order to initiate appropriate therapy. 47 of the 51 patients underwent complete radical hysterectomy and pelvic lymphadenectomy. Our experience and philosophy regarding this mode of primary therapy in stage, one, cervical cancer has previously been reported. The major complication rate of 11.8% is similar to that found by one of the authors in a previous study. It is difficult to say what part the radical therapy played in obtaining a survival of 100%. A variety of therapeutic modalities have been used and many show equally good results. One wonders how many patients who are treated for microinvasive carcinoma are found upon critical review of the surgical material to have an cyto carcinoma or an even lesser process. And cyto carcinoma involving glands deep within the stroma is often confusing, particularly if a dense inflammatory infiltrate obscures the borders of the glands. Five cases were thus excluded from our study. Border differentiation of the invasive tumor occurred in an average of 81.3% of the cases in this study. Regardless of the depth of invasion, it would appear that this would be a useful histologic feature in distinguishing micro invasion from inside two carcinoma with gland involvement. The results of our study do not justify strong recommendations for radical hysterectomy and pelvic lymphadenectomy. In all patients, it would appear that if the cone margins are free of disease, then conservatism in the form of an extra facial abdominal hysterectomy with conservation of one or both ovaries in the young patient would be adequate therapy. The fact that two of our cases had second primary malignancies and the desirability of at least palpating and sampling suspicious lymph nodes militates against the use of simple vaginal hysterectomy as adequate primary therapy for the young patient who strongly desires further pregnancies, conization as interim therapy may be considered only in the context of assured follow up with pap smears and colposcopy and then only when there is minimal disease and the cone margins are free of disease. In all other cases, the high incidence of residual disease and the possibility of invasion deeper than five millimeters. As in the case in our series warrants the use of radical hysterectomy with or without lymphadenectomy. Therapeutic philosophies will differ and individualization continues to be the hallmark of high quality medical practice. We take no issue with those who choose to treat patients with cl space invasion or a confluent growth pattern in a more radical manner. Although the results of our study and that of roach and Norris cast doubt on the ominous nature of these findings. However, we feel that these findings per se should not exclude these cases from the classification of microinvasive carcinoma stage one a in statistical reports until we are better able to define the microinvasive lesion and the point in its evolution at which it becomes biologically similar in its lethal potential to frankly invasive carcinoma. We must approach this disease with caution from both a diagnostic and therapeutic standpoint. Thank you. This program was produced through the mobile facilities of the television branch, Health Sciences, media division, Academy of Health Sciences, United States Army, Fort Sam Houston, Texas.