Long-Term Outcome of Fetuses with Soft Marker and Without Genetic or Structural Abnormality.

PURPOSE: To determine long-term outcome of infants with isolated or multiple soft markers but no structural or chromosomal abnormalities. METHODS: A retrospective study of 78 pregnant women who were referred for amniocentesis and found to have soft markers including echogenic intracardiac focus/foci (EIF), echogenic bowel (EB), unilateral or bilateral choroid plexus cysts, (UCPCs or BCPCs) mild pyelectasis and single umbilical artery but no structural anomalies and outcomes of the liveborns with a 4- to 9-year follow-up was conducted. RESULTS: Among 28 fetuses with EIF, allergic asthma and epilepsy were diagnosed in two liveborns. We followed up nine pregnancies with EB, epilepsy was present in one case. Allergic asthma was detected in both UCPCs and BCPCs, whereas epilepsy and attention-deficit/hyperactivity disorder (ADHD) were diagnosed in two liveborns with BCPCs. Twelve liveborns with multiple soft markers were evaluated; no pathology was detected in most of them except one case of allergic asthma, one case of hearing impairment and one case of ADHD. CONCLUSIONS: This study shows longer-term favorable outcomes of the liveborns with isolated or multiple soft markers without any aneuploidy and may provide insight into this debated point.

Leiomyoma With Bizarre Nuclei: Clinical and Pathologic Features of 30 Patients.

Leiomyoma with bizarre nuclei (LBN) have significant cytologic atypia, but high mitotic rate and tumor cell necrosis are absent. Although it is a benign leiomyoma variant, recurrent cases have been described. In this study, we investigated the clinical and pathologic features of LBN and compared them with related studies. A total of 30 patients diagnosed with LBN in our department were included in this study. In all cases, clinical data (age, complaint, surgery type), macroscopic features (size, location, number of leiomyomas, necrosis, and hemorrhage), microscopic features (bizarre cell distribution, bizarre cell density, cellularity, mitotic rate, tumor margin, necrosis, nuclear pseudoinclusions, karyorrhectic nuclei, prominent eosinophilic nucleoli with perinucleolar clearing, cytoplasmic eosinophilic inclusions, staghorn vessels, and alveolar-type edema), and follow-up data (recurrence and survival period) were evaluated. The mean age of the patients was 49.76 yr (range: 38-89 yr). Twenty-two patients (73%) had undergone hysterectomy and 8 patients (27%) had undergone myomectomy. The mean tumor diameter was 6.12 cm (range: 0.5-25 cm). The tumor was intramural in 11 patients (37%), subserosal in 7 patients (23%), and submucosal in 4 patients (13%). Microscopically, the bizarre cell distribution was focal in 8 patients (27%), multifocal in 12 patients (40%), and diffuse in 10 patients (33%). Bizarre cell density was low in 15 patients (50%), intermediate in 8 patients (27%), and high in 7 patients (23%). The mean mitotic count was 1.4 (0-4) in 10 high-power fields, and the tumor margin was regular in all cases. We observed pseudoinclusions in 24 of 30 (80%) tumors, karyorrhectic nuclei in 21 of 30 tumors (70%), prominent eosinophilic nucleoli with perinucleolar clearing in 12 tumors (40%), cytoplasmic eosinophilic inclusions in 11 tumors (37%), staghorn vessels in 9 tumors (30%), and alveolar-type edema in 9 tumors (30%). In addition, we examined the follow-up records of 26 patients (average duration: 58.1 mo). One patient had a smooth muscle tumor in the L3-L4 paravertebral region at 67 mo after hysterectomy. This tumor did not share similar microscopic and immunohistochemical findings to the patient's earlier uterine tumor. The definitive diagnosis of uterine smooth muscle tumors is important for the determination of the prognosis of the patient and the most appropriate therapeutic approach. As in several recent studies, our series has shown that LBN has a benign clinical course. However, other malignant morphologic criteria such as high mitotic rate and tumor cell necrosis should be excluded in the diagnosis of LBN.

Serum VEGF and PGF may be significant markers in prediction of severity of preeclampsia.

OBJECTIVE: The aim of this study evaluate the value of vascular endothelial growth factor (VEGF) and placental growth factor (PGF) serum levels in prediction of preeclampsia, severity and onset time of the disease. METHODS: Twenty five placentas of pregnant women diagnosed with preeclampsia (15 severe preeclampsia, 10 mild preeclampsia) and peripheral venous blood samples were collected. The placental and serum levels of VEGF and PGF were measured. RESULTS: VEGF level was significantly higher in cases and the optimal cut-off point was calculated as 600.5 to differentiate the cases and the controls, with 64% sensitivity and 100% specificity. There was a significant increase in median serum level of VEGF in severe cases compared to the mild cases and the controls. The optimal cut-off point for VEGF was calculated as 673.5 to differentiate mild and severe cases, with 93.3% sensitivity and 90% specificity. Whereas, PGF was significantly lower in severe cases than that in the mild cases and controls. The optimal cut-off point for PGF was calculated as 16.1 to differentiate mild and severe cases, with 66.7% sensitivity and 100% specificity. CONCLUSION: VEGF and PGF may be significant markers in prediction of severity of preeclampsia, and VEGF may also be valuable in prediction of preeclampsia.

Role of vascular endothelial growth factor and placental growth factor expression on placenta structure in pre-eclamptic pregnancy.

AIM: Pre-eclampsia is a hypertensive disease that is characterized by high blood pressure and proteinuria after 20 gestational weeks and complicates 3-8% of all pregnancies. It is classified as either mild or severe pre-eclampsia according to severity, and the aim of this study was to investigate the structural differences between these two classifications. METHODS: Placenta samples were collected from 68 women who underwent cesarean delivery. Total volume of villi and numerical density of vascular endothelial growth factor (VEGF)- and placental growth factor (PIGF)-positive cells were estimated on stereology and evaluated using one-way ANOVA. RESULTS: There was no significantly difference in total villi volumes between the groups (P > 0.05). In contrast, on immunohistochemistry, the numerical density of VEGF-positive cells in severe pre-eclampsia was significantly different to the control and mild pre-eclampsia groups (P<0.05). Additionally, the numerical density of PIGF-positive cells in the mild and severe pre-eclampsia group was significantly higher than in the control group (P<0.01). CONCLUSION: There is no relationship between villi volume and pre-eclampsia, although growth factors play a role in placental changes. The present results were supported by histopathology and several studies in the literature.

Do Leukocyte and Platelet Counts Have Benefit for \Preoperative Evaluation of Endometrial Cancer?

PURPOSE: The aim of this study was to investigate the association between preoperative leukocyte and platelet counts and the stage of the disease in patients with endometrial cancer. MATERIALS AND METHODS: Data for 100 patients undergoing total abdominal hysterectomy and bilateral salpingoophorectomy for benign uterine diseases and 177 patients surgically staged for endometrial cancer at Ondokuz Mayis University, Department of Gynecology and Obstetrics between 2005 and 2013, with preoperative complete blood count in the week prior to surgery including WBC, platelet count, pathologic evaluation for both benign and malign endometrium lesions, tumor stage and presence of lymphovascular space invasion (LVI), were retrospectively analyzed. RESULTS: The preoperative leukocyte count was significantly higher in patients with endometrial cancer when compared to the patients with benign diseases. However, there were no significant differences in platelet counts between the groups. Patients with advanced stage endometrial cancer had higher preoperative leukocyte counts when compared to the early stage disease whereas there was no difference in platelet count. Multivariate regression analysis identified preoperative leukocytosis as an independent prognostic factor for endometrial cancer. The optimal cut-off point for WBC was calculated as 10,500 to differentiate stage 1-2-3 and 4 with 88.9% sensitivity and 86.3% specificity (AUC: 0.901, 95% CI: 0.829-0.973, p<0.001, PPV: 25.8%, NPV: 99.3%). CONCLUSIONS: Preoperative leukocytosis is independently associated with advanced endometrial cancer.

Is Surgical Staging Necessary for Patients with Low-risk Endometrial Cancer? A Retrospective Clinical Analysis.

PURPOSE: The aim of this study was to compare the tumor-free and overall survival rates between patients with low-risk endometrial cancer who underwent surgical staging and those who did not undergo surgical staging. MATERIALS AND METHODS: Data, including demographic characteristics, grade of the tumor, myometrial invasion, cervical involvement, peritoneal washing, lymph node involvement, lymphovascular space invasion, postoperative complication, adjuvant treatment, cancer recurrence, and tumor-free and overall survival rates, for patients with low-risk endometrioid endometrial cancer who were treated surgically with and without pelvic and paraaortic lymph node dissection (LND) were analyzed retrospectively. The patients diagnosed with endometrioid endometrial cancer including the following criteria were considered low-risk: 1) a grade 1 (G1) or grade 2 (G2) endometrioid histology; 2) myometrial invasion of <50% upon magnetic resonance imaging (MRI); 3) no stromal glandular or stromal invasion upon MRI; and 4) no evidence of intra-abdominal metastasis. Then the patients at low-risk were divided into two groups; group 1 (n=117): patients treated surgically with pelvic and paraaortic LND and group 2 (n=170): patients treated surgically without pelvic and paraaortic LND. RESULTS: There was no statistical significance when the groups were compared in terms of lymphovascular space invasion, cervical involvement, positive cytology, and recurrence, whereas the administration of an adjuvant therapy was higher in group 2 (p<0.005). The number of patients with positive pelvic nodes and the number of metastatic pelvic nodes were significantly higher in the group with positive LVI than in the group without LVI (p<0.005). No statistically significant differences were detected between the groups in terms of tumor-free survival (p=0.981) and overall survival (p=0.166). CONCLUSIONS: Total hysterectomy with bilateral salpingo-oophorectomy and stage-adapted postoperative adjuvant therapy without pelvic and/or paraaortic lymphadenectomy may be safe and efficient treatments for low-risk endometrial cancer.

Platelet Indices May be Useful in Discrimination of Benign and Malign Endometrial Lesions, and Early and Advanced Stage Endometrial Cancer.

BACKGROUND: The aim of this study was to investigate the predictive value of white blood cells (WBC), the neutrophil to lymphocyte ratio (NLR), platelet indices including mean platelet volume (MPV), platelet distribution width (PDW), platelet crit (PCT) and platelet to lymphocyte ratio (PLR) in discrimination between benign and malign endometrial lesions, and early and advanced stage endometrial adenocarcinomas. MATERIALS AND METHODS: Data for 105 patients undergoing total abdominal or vaginal hysterectomy for benign uterine diseases and 114 patients surgically staged for endometrium adenocarcinoma at Ondokuz Mayis University, Department of Gynecology and Obstetrics, between 2008 and 2014, were collected. Parameters were preoperative and postoperative complete blood counts in the week prior to surgery with differentials including WBC, platelet count, platelet indices (MPV, PCT, PDW), NLR and PLR. Pathologic evaluations for both benign and malign endometrium lesions, grade of endometrium adenocarcinoma, tumor stage, presence of lymphovascular space invasion (LVI) were retrospectively analyzed. RESULTS: Regarding definitive factors in discriminating patients with endometrium cancer from those with benign diseases, MPV was significantly increased in the malign group whereas there was a significant decrease in the PDW value compared to the benign group. The best cut-off value in differentiation of the benign and malign groups, malign cases were found to increase over the value of 7.54 for MPV, and under 37.8 for PDW. When definitive factors in discrimination of early stage endometrium cancer from advanced stage disease and LVI in the malign group were evaluated according to the ROC analysis, no significant relation was detected between blood parameters and the stage and the LVI of the disease. CONCLUSIONS: MPV and PDW may have predictive value in the discrimination of benign and malign endometrium diseases. Nevertheless, since there have been few reports on this topic, further large-scale prospective studies are necessary.

Primary vulvar lymphangioma circumscriptum: a case report and review of literature.

OBJECTIVE: To add a new case of primary vulvar lymphangioma circumscriptum to the literature and to review the current literature. MATERIALS AND METHODS: We searched the PubMed/MEDLINE databases for previous case reports using the key words "vulvar lymphangioma circumscriptum" and "primary vulvar lymphangioma circumscriptum." RESULTS: We found 21 cases of primary vulvar lymphangioma circumscriptum reported until 2013. Mean age was 32 years (range = 3-76 y), and 62 % of the cases had been treated surgically. CONCLUSIONS: The treatment of primary vulvar lymphangioma circumscriptum is mainly surgery. Depending on the age of the patient and the extent of lesion, surgical treatment might be in the form of the local excision, labiectomy, or vulvectomy.

May the platelet to lymphocyte ratio be a prognostic factor for epithelial ovarian cancer?

BACKGROUND: The study aimed to evaluate changes in hematologic parameters, including white blood cell, platelet count, platelet indices, the platelet to lymphocyte and neutrophil to lymphocyte ratios in patients with early and advanced stages of epithelial ovarian cancers. MATERIALS AND METHODS: The study included 100 patients with epithelial ovarian cancer who underwent primary staging exploratory laparotomy. Preoperative hematologic parameters, tumor histopathologic type, grade, stage and serum CA-125 levels were retrospectively analyzed. These parameters were compared between the patients with early (stage I-II) and advanced (stage III-IV) ovarian cancer. RESULTS: White blood cell count and platelet indices, including mean platelet volume, platelet distribution width and platelet crit did not show a statistically significant difference between groups with early and advanced ovarian cancer. However, the neutrophil to lymphocyte ratio, platelet count, the platelet to lymphocyte ratio and CA-125 level showed a statistically significant difference between the two groups (p<0.05, p<0.01, p<0.001, p<0.01 respectively). CONCLUSIONS: It was found that the neutrophil to lymphocyte ratio, platelet count and the platelet to lymphocyte ratio increased with the increasing stage of ovarian cancer. Furthermore, it was seen that the platelet to lymphocyte ratio is an independent prognostic factor related to the stage of epithelial ovarian cancer.

Multicenter analysis of gestational trophoblastic neoplasia in Turkey.

BACKGROUND: To evaluate the incidence, diagnosis and management of GTN among 28 centers in Turkey. MATERIALS AND METHODS: A retrospective study was designed to include GTN patients attending 28 centers in the 10-year period between January 2003 and May 2013. Demographical characteristics of the patients, histopathological diagnosis, the International Federation of Gynecology and Obstetrics (FIGO) anatomical and prognostic scores, use of single-agent and multi-agent chemotherapy, surgical interventions and prognosis were evaluated. RESULTS: From 2003-2013, there were 1,173,235 deliveries and 456 GTN cases at the 28 centers. The incidence was calculated to be 0.38 per 1,000 deliveries. According to the evaluated data of 364 patients, the median age at diagnosis was 31 years (range, 15-59 years). A histopathological diagnosis was present for 45.1% of the patients, and invasive mole, choriocarcinoma and PSTTs were diagnosed in 22.3% (n=81), 18.1% (n=66) and 4.7% (n=17) of the patients, respectively. Regarding final prognosis, 352 (96.7%) of the patients had remission, and 7 (1.9%) had persistence, whereas the disease was mortal for 5 (1.4%) of the patients. CONCLUSIONS: Because of the differences between countries, it is important to provide national registration systems and special clinics for the accurate diagnosis and treatment of GTN.

Regression of experimentally induced endometriosis with a new selective cyclooxygenase-2 enzyme inhibitor.

BACKGROUND: Cyclooxygenase-2 (COX-2) levels increase in women with endometriosis. COX-2, via increasing prostaglandin E2, contributes to an increase in vascular endothelial growth factor. In this way, COX-2 may contribute to the progression and continuity of endometriosis. We investigated the effect of dexketoprofen trometamol, a new selective COX-2 enzyme inhibitor, on experimentally induced endometriotic cysts. METHODS: Experimental endometriotic cysts were created in 60 adult female Wistar albino rats. The rats were randomized to 2 equal groups, a control (group Con) and a dexketoprofen (group Dex) group. Six weeks later, cyst volumes were measured as in vivo (volume 1). Following volume 1 measurement, for 4 weeks group Con received 0.1 ml distilled water; group Dex received 0.375 mg dexketoprofen trometamol/0.1 ml distilled water, intramuscularly, twice a day. At the end of administration, the cyst volumes were remeasured (volume 2), and the cysts totally excised and weighed. Glandular (GT) and stromal tissues (ST) and natural killer (NK) cell contents in the cyst wall were scored. RESULTS: NK cell content and volume 1 were not different between the 2 groups. Volume 2, cyst weight, and GT and ST contents in group Dex were significantly lower than those in group Con. CONCLUSION: Dexketoprofen trometamol significantly reduced the development of experimentally induced endometriotic cysts both macroscopically and microscopically.

Effect of vitamin C on the growth of experimentally induced endometriotic cysts.

AIM: The aim of this study was to investigate the effect of vitamin C on the growth of experimental endometriotic cysts. MATERIAL AND METHODS: The endometrium of the uterine horn wall (diameter, 4 mm) was implanted onto the inner surface of the anterior abdominal wall of 40 Wistar albino adult female rats, by laparotomy. The day after the implantation, the rats were randomly assigned into four groups (control group and experimental groups [V1, V2, and V3]) comprising 10 rats each. For 6 weeks, the control group (Group C) received 1 mL distilled water, whereas the experimental groups (Groups V1, V2, and V3) received 0.5 mg, 1.25 mg, and 2.5 mg of vitamin C in 1 mL of distilled water, respectively. The doses were given via oral gavage once per day. At the end of the administration, a second laparotomy was performed and endometriotic cyst volumes and weights of rats among the groups were compared. In addition, the stromal and glandular tissue and the natural killer cell contents of the cysts were compared among the groups. RESULTS: The cyst volume in Group V3 and the cyst weights in Groups V2 and V3 were significantly lower than those in Group C. The natural killer cell content in Groups V1, V2, and V3 was significantly lower than that in Group C. Stromal and glandular tissue contents of the groups were not significantly different. CONCLUSIONS: The dose-dependent vitamin C supplementation significantly reduced the volumes and weights of the endometriotic cysts.

Possible effects of endometriosis-related immune events on reproductive function.

PURPOSE: To examine possible effects of endometriosis-related immune events on reproductive function. METHODS: The synthesis and review of the relevant current literature in English language. RESULTS: The endometriosis-related immune events may have a negative impact on almost all components of the reproductive function including fallopian tube function, oocyte quality, sperm function, fertilization, embryo quality, endometrial receptivity, implantation and placentation. CONCLUSIONS: An important portion of the cases of infertility or miscarriage seen in women with endometriosis may be due to some immunological alterations associated with endometriosis.

Relationship between endometriosis and cancer from current perspective.

PURPOSE: To examine the current mechanisms of the increased incidence of cancer in women with endometriosis. METHODS: The synthesis and review of the relevant current literature in English language. RESULTS: Compared with general population, women with endometriosis have two times higher risk for developing ovarian cancer, 30% higher risk for developing breast cancer, and 40% higher risk for developing hematopoietic malignancies, mainly non-Hodgkin lymphoma. CONCLUSIONS: Endometriosis comprises many predisposing factors including genetic, epigenetic, local environmental, hormonal, inflammatory and immunologic changes, for the development of some cancers.

Comparison of the effects of raloxifene and anastrozole on experimental endometriosis.

OBJECTIVE: To compare the efficacies of anastrozole and raloxifene on endometriosis. STUDY DESIGN: A randomized, placebo-controlled, single-blind, experimental study was performed on 45 adult Wistar female rats in the Experimental Surgery Laboratory at Ondokuz Mayis University in Turkey. Endometrial tissues were implanted on the abdominal peritoneum in 45 rats. Six weeks later, the implant volumes were measured (volume-1) by performing a second laparotomy. Rats were randomized to one of three equal study groups. Saline solution (0.1 cc/rat/week, subcutaneously) was administered to group 1 (control group), anastrozole (0.004 mg/rat/day, orally) to group 2 (anastrozole group), and raloxifene (0.24 mg/rat/day, orally) to group 3 (raloxifene group) for 8 weeks. At the end of administration, a third laparotomy was performed to remeasure implant volumes (volume-2), and implants were totally excised for histopathologic examination. Volume-1 and volume-2 within the groups, as well as stromal and glandular tissues between the groups, were compared. RESULT(S): In the anastrozole and raloxifene groups, volume-2 values were significantly lower than those of volume-1. When compared to the control group, in both anastrozole and raloxifene groups, while glandular tissue scores were found significantly lower, stromal tissue scores were not different than that of the control group. There was no significant difference between both the GT and ST scores of the anastrozole and raloxifene groups. CONCLUSION(S): Anastrozole and raloxifene were seen to have caused equally the regression of the experimental endometriosis statistically significantly.

Vulvar lymphangioma circumscriptum presenting periodic symptoms.

The authors report a case of acquired lymphangioma circumscriptum (LC), localised in the right labium majus of vulva and characterised by periodic symptoms for 8 years; however, 3 months after the right major labiectomy, the same symptoms developed in both the left labium majus and the right labium minus. To the best of our knowledge, this is the first case of acquired LC with this type of localisation and symptoms without any known aetiologic factor.

Rhabdomyosarcoma arising in a mature cystic teratoma with contralateral serous carcinoma: case report and review of the literature.

SUMMARY: Malignant transformation of a mature cystic teratoma of the ovary is rare, and occurs in approximately 2% of all cases. The most common malignancy arising in mature cystic teratoma is squamous cell carcinoma. Sarcomas very rarely develop in mature cystic teratoma. We describe the case of a 65-year-old patient with mature cystic teratoma, and with rhabdomyosarcomatous transformation and contralateral serous carcinoma. To our knowledge, this is the first case of a pure rhabdomyosarcoma arising in a mature cystic teratoma. The clinicopathologic and immunohistochemical findings of this exceptional case are reported and the literature is reviewed.

Comparison of the effects of cetrorelix, a GnRH antagonist, and leuprolide, a GnRH agonist, on experimental endometriosis.

AIM: In the present study, we aimed to compare the effects of cetrorelix and leuprolide on endometriosis. METHODS: This randomized, placebo-controlled, single-blind, experimental study was performed on 45 Wistar adult female rats in the Experimental Surgery Laboratory at Ondokuz Mayis University. After the peritoneal implantation of endometrial tissue, rats were randomized to three equal intervention groups: (i) control group, (ii) leuprolide group, and (iii) cetrorelix group. Six weeks later, following implant volume measurements (volume-1) by performing a second laparotomy, saline (0.1 cc/rat) was administered subcutaneously to the control group once a week, leuprolide (0.075 mg/kg) subcutaneously to the leuprolide group twice at 4-week intervals and cetrorelix (0.001 mg/rat/day) subcutaneously to the cetrorelix group for 8 weeks. At the end of the treatment, by performing a third laparotomy, implant volumes were remeasured (volume-2) and implants were totally excised for histopathological examination. The volume-1 and volume-2 values within the groups, and stromal and glandular tissue scores between the groups were compared. RESULTS: In both the leuprolide group and the cetrorelix group, volume-2 as compared to volume-1 had significantly reduced (P < 0.01, P < 0.01 respectively), while there was no significant volume change in the control group (P > 0.05). In this group, when compared with the control group, glandular and stromal tissues had significantly lessened (P < 0.01, P < 0.01 respectively). CONCLUSION: Leuprolide and cetrorelix were found to have similar efficacy in the regression of both the size and the histological structure of experimental endometriotic implants.

Efficacy of imiquimod, an immunomodulatory agent, on experimental endometriosis.

OBJECTIVE: To investigate the efficacy of imiquimod on endometriosis. DESIGN: Randomized, placebo-controlled, single-blind, experimental study. SETTING: Experimental surgery laboratory at a university in Turkey. ANIMAL(S): Thirty Wistar female rats. INTERVENTION(S): After the peritoneal implantation of endometrial tissue, rats were randomized to two equal intervention groups: [1] the control group and [2] the imiquimod group. Six weeks later, after implant volume was measured (volume 1) by performing a second laparotomy, imiquimod (10 mg intraperitoneally per rat, 2 times per wk) was administered to the imiquimod group, and saline solution (0.1 mL SC, once per wk), to the control group, for 8 weeks. At the end of the treatment, a third laparotomy was performed to remeasure implant volumes (volume 2), and implants were totally excised for histopathologic examination. MAIN OUTCOME MEASURE(S): To compare volume 1 and volume 2 within the groups, as well as stromal and glandular tissues between the groups. RESULT(S): In the imiquimod group, volume 2 was statistically significantly reduced compared with volume 1, whereas there was no significant volume change in the control group. In the imiquimod group, when compared with the control group, both glandular and stromal tissues had statistically significantly lessened. CONCLUSION(S): Imiquimod was seen to regress significantly both the size and the histological structure of endometriotic implants.

Efficacy of recombinant human interferon alpha-2b on experimental endometriosis.

OBJECTIVE: To investigate the efficacy of recombinant human interferon alpha-2b on endometriosis. STUDY DESIGN: The randomized, placebo-controlled, single-blind, experimental study was performed on 30 Wistar female rats in the Experimental Surgery Laboratory at Ondokuz Mayis University in Turkey. After the peritoneal implantation of endometrial tissue, rats were randomized to two equal intervention groups: (1) the control group and (2) the interferon group. Six weeks later, after implant volume was measured (volume-1) by performing a second laparotomy, interferon alpha-2b (100,000 IU subcutaneously per rat, three times at 48 h intervals) was administered to the interferon group, and saline solution (0.1 ml SC, once per week), to the control group, for 8 weeks. At the end of the treatment, a third laparotomy was performed to remeasure implant volumes (volume-2), and implants were totally excised for histopathologic examination. Volume-1 and volume-2 within the groups, as well as stromal and glandular tissues between the groups were compared. RESULTS: In the interferon group, volume-2 was statistically significantly reduced compared with volume-1, whereas there was no significant volume change in the control group. In the interferon group, when compared with the control group, both stromal and glandular tissues had statistically significantly lessened. CONCLUSIONS: Interferon alpha-2b was seen to regress significantly both the size and the histological structure of endometriotic implants.