Massive platelet-rich thrombus formation in small pulmonary vessels in amniotic fluid embolism: An autopsy study.

OBJECTIVE: To identify pulmonary/uterine thrombus formation in amniotic fluid embolism (AFE). DESIGN: Retrospective, observational. SETTING: Nationwide. POPULATION: Eleven autopsy cases of AFE and control cases. METHODS: We assessed pulmonary and uterine thrombus formation and thrombus area in AFE and pulmonary thromboembolism (PTE) as a control. The area of platelet glycoprotein IIb/IIIa, fibrin, neutrophil elastase, citrullinated histone H3 (a neutrophil extracellular trap marker) and mast cell chymase immunopositivity was measured in 90 pulmonary emboli, 15 uterine thrombi and 14 PTE. MAIN OUTCOME MEASURES: Pathological evidence of thrombus formation and its components in AFE. RESULTS: Amniotic fluid embolism lung showed massive thrombus formation, with or without amniotic emboli in small pulmonary arteries and capillaries. The median pulmonary thrombus size in AFE (median, 0.012 mm2 ; P < 0.0001) was significantly smaller than that of uterine thrombus in AFE (0.61 mm2 ) or PTE (29 mm2 ). The median area of glycoprotein IIb/IIIa immunopositivity in pulmonary thrombi in AFE (39%; P < 0.01) was significantly larger than that of uterine thrombi in AFE (23%) and PTE (15%). The median area of fibrin (0%; P < 0.001) and citrullinated histone H3 (0%; P < 0.01) immunopositivity in pulmonary thrombi in AFE was significantly smaller than in uterine thrombi (fibrin: 26%; citrullinated histone H3: 1.1%) and PTE (fibrin: 42%; citrullinated histone H3: 0.4%). No mast cells were identified in pulmonary thrombi. CONCLUSIONS: Amniotic fluid may induce distinct thrombus formation in the uterus and lung. Pulmonary and uterine thrombi formation may contribute to cardiorespiratory collapse and/or consumptive coagulopathy in AFE.

[Subtotal Stomach-Preserving Pancreaticoduodenectomy for Large Laterally Spreading Early Duodenal Cancer-A Case Report].

A 76-year-old man came to our hospital for a close examination after an abnormal finding during a medical checkup. Upper gastrointestinal endoscopy revealed a circumferential flat lesion with irregularity in the second to third portions of the duodenum. Biopsy diagnosed papillary adenocarcinoma. Contrast-enhanced CT of the abdomen showed no evidence of lymph node enlargement and distant metastasis. Endoscopic depth of the lesion was estimated to be intramucosal carcinoma, but it was approximately 60 mm in size, circumferential, and located near the papilla Vater. Therefore, endoscopic resection was deemed difficult. Subtotal stomach-preserving pancreaticoduodenectomy was performed. Postoperative pathological examination revealed type 0-Ⅱa, tub1>pap, pTis, Ly0, V0, 80×50 mm, BD1, Ex0, Pn0, pPM0, pDM0, pN0, pStage 0. There has been no recurrence since then. Lateral spreading duodenal carcinoma is a rare disease, and endoscopic resection, local resection, and pancreaticoduodenectomy have been reported as treatment options. We report a case of resection of a large lateral spreading duodenal carcinoma with a review of the literature.

Bcl-2-negative IGH-BCL2 translocation-negative follicular lymphoma of the thyroid differs genetically and epigenetically from Bcl-2-positive IGH-BCL2 translocation-positive follicular lymphoma.

AIMS: Follicular lymphoma (FL), comprising a minor subset of primary thyroid lymphomas, is divided into two groups based on Bcl-2 expression and IGH-BCL2 translocation. The clinicopathological features exhibited by Bcl-2-negative IGH-BCL2 translocation-negative FL of the thyroid (Bcl-2- /IGH-BCL2- tFL) are different from those of conventional FL; however, its lymphomagenesis remains unclear. Here, we collected samples from seven patients with Bcl-2- /IGH-BCL2- tFL to investigate their epigenetic and genetic aberrations. METHODS AND RESULTS: The immunohistochemical profiles of epigenetic modifiers and the methylation status of histones were examined, including EZH2, MLL2/KMT2D, CBP/CREBBP, EP300, H3K27me3 and H3K4me3, in Bcl-2- /IGH-BCL2- tFL and Bcl-2-positive IGH-BCL2 translocation-positive FL of the thyroid (Bcl-2+ /IGH-BCL2+ tFL). Most Bcl-2- /IGH-BCL2- tFLs retained the positivity of epigenetic modifiers and lower expression of H3K27me3, although Bcl-2+ /IGH-BCL2+ tFLs exhibited aberrant immunohistochemical patterns of EZH2 and CBP/CREBBP and overexpression of H3K27me3. Samples from seven cases were further analysed using targeted sequencing, focusing on the exons of 409 key tumour suppressor genes and oncogenes. Bcl-2- /IGH-BCL2- tFLs do not have pathogenic mutations of epigenetic modifiers, such as EZH2, MLL2/KMT2D, MLL3/KMT2C, EP300 and ARID1A, which have been reported in FLs in the literature, whereas Bcl-2+ /IGH-BCL2+ tFLs are probably pathogenic/pathogenic missense mutations or frameshift mutations of these genes. Additionally, novel mutations in TET2 and EP400 were detected in Bcl-2- /IGH-BCL2- tFLs. CONCLUSIONS: Different genetic and epigenetic abnormalities might be involved in the oncogenesis of Bcl-2- /IGH-BCL2- tFLs from Bcl-2+ /IGH-BCL2+ tFLs and other FLs.

Maternal death analysis based on data from the nationwide registration system in Japan (2010-2018).

The maternal mortality rate in Japan was 3.5 per 100 000 live births in 2017, similar to that reported in other developed countries. To reduce the number of maternal deaths, a Japanese nationwide registration and analysis system was implemented in 2010. Between January 2010 and April 2018, 367 maternal deaths were reported. Among them, by reviewing 80 autopsy records, the direct obstetric causes of death were identified in 52 women. The major causes of deaths were amniotic fluid embolism and acute pulmonary thromboembolism. The other 26 maternal deaths were associated with indirect obstetric causes including invasive Group A Streptococcus infection, aortic dissection, cerebral stroke and cardiomyopathies. This review highlights the importance of autopsy in maternal deaths. On analyzing 42 autopsy specimens obtained from registered cases of maternal death during 2012-2015, the 36% of causes of death by autopsy were discordant with the clinical diagnosis. Moreover, of the 38% of non-autopsied maternal death, the cause of death could not be clarified from the clinical chart. We emphasized that detailed autopsies are necessary to clarify the precise pathologic evidence related to pregnancy and delivery, especially causes of unexpected death such as amniotic fluid embolism.

[Small Bowel Metastasis of Breast Cancer-A Case Report].

A 69-year-old female had hormone therapy for liver metastasis after surgery for right breast cancer. She came to the hospital with a complaint of abdominal pain and was admitted with a diagnosis of small bowel obstruction. She had previously undergone surgery for an ovarian tumor and was suspected of having an intestinal obstruction caused by adhesions in her pelvis. She promptly improved with conservative treatment of fasting only. In the following months, she developed 2 intestinal obstructions, and CT scan revealed a neoplastic lesion in the small intestine. With the diagnosis of small intestinal tumor, laparoscopic surgery was performed. A neoplastic lesion was found in the ileum. A small bowel resection was performed. She was discharged with a good postoperative course. The pathological results showed breast cancer metastasis in the small intestine. Based on the diagnosis, postoperative chemotherapy has been started. Gastrointestinal metastasis of breast cancer is relatively rare and rarely causes clinical problems. We report a case of small intestinal metastasis of breast cancer.

[Right Hemicolectomy and Pancreatoduodenectomy for Transverse Colon Cancer Invasion to the Duodenum-A Case Report].

A 74-year-old woman visited her local doctor with stomach ache and weight loss. Abdominal ultrasonography showed a mass in the hepatic flexure of the transverse colon. She was referred to our hospital. Colonoscopy revealed transverse colon cancer in the hepatic flexure. Upper endoscopy showed redness of the mucosa and stenosis in the descending portion of the duodenum. Therefore, duodenal invasion was suspected. The CT scan showed a regional lymph node metastasis, but there were no obvious signs of distant metastases. From the aforementioned findings, we diagnosed the patient with duodenal invasion of transverse colon cancer(cT4b, N1, M0, cStage Ⅲ). There was no intraoperative peritoneal dissemination or liver metastasis, and we performed right hemicolectomy and pancreatoduodenectomy for transverse colon cancer. On histopathological examination, we diagnosed pT4b(Duo, Pan), N1b(3/35), M0, pStage Ⅲb. The patient had delayed gastric emptying after surgery. She recovered conservatively and was discharged on POD 37. She underwent adjuvant chemotherapy( capecitabine therapy)and has been alive without recurrence 8 months after surgery. In some cases of colon cancer invasion of other organs, long-term survival can be achieved if R0 resection is possible, and we should consider extended resection.

[A Resected Case of Angiomyolipoma Difficult to Be Distinguished from Hepatocellular Carcinoma].

A 42-year-old man complaining of left back pain was admitted to our hospital. The hepatis B and C surface antigens were negative. The serum levels of tumor markers were within the reference ranges. Abdominal ultrasound revealed an 8 cm-sized, primarily round and hyperechoic mass in the left lateral segment. Contrast-echo showed non-uniform enhancement in the arterial phase and uniform enhancement in the portal phase. This mass did not indicate"wash-out"on contrast- enhanced CT. It showed hypointensity in the hepatobiliary phase on MRI. The definitive diagnosis could not be obtained, and the patient was suspected with malignancy, such as hepatocellular carcinoma(HCC). Therefore, left hemi-hepatectomy was performed for the diagnostic treatment. Based on the immunochemical staining results, he was diagnosed with angiomyolipoma( AML). AML is composed of fat, blood vessels, and smooth muscles. It is regarded as a tumor of perivascular epithelioid cell tumor(PEComa). Early venous return and adipose tissues in the tumor were the distinctive features of this tumor. The preoperative diagnosis of AML without any fatty component as in this case is very difficult.

[A Case of Resected Peritoneal Metastasis from Hepatocellular Carcinoma after Surgery].

A 69-year-old woman with a hepatocellular carcinoma(HCC)was followed-up for type B chronic hepatitis and underwent partial hepatectomy(S6)at our hospital. Afterwards, she underwent radiofrequency ablation(RFA)therapy twice because of intrahepatic recurrence. Seven months after the first hepatectomy, a left adrenalectomy was performed for a left adrenal metastasis. Seventeen months after the first hepatectomy, a splenectomy was performed for a splenic metastasis. Forty-three months after the first hepatectomy, a second hepatectomy was performed for intrahepatic recurrence, and a right adrenalectomy was performed for an adrenal metastasis. Sixty-eight months after the first hepatectomy, an abdominal CT revealed a growing solitary lesion in the ascending colon, which was diagnosed as a peritoneal metastasis. The peritoneal dissemination was removed because there were no other extrahepatic or intrahepatic recurrences. Histologically, the resected specimen was diagnosed as a peritoneal metastasis from a HCC. The patient survived, and there were no recurrences for 6 months after the operation. We report this case of a peritoneal metastasis from a HCC after surgery with a review of the literature.

[AFP and PIVKA-â ¡ Producing Gastric Cancer with Metachronous Liver Metastasis after Gastrectomy-A Case Report].

A 67-year-old man visited his doctor because of anorexia and was diagnosed with gastric cancer based on endoscopic findings. Endoscopy revealed a 0-Ⅰ type tumor, 6 cm in size, at the gastric angle. Preoperative CT showed no apparent lymph node or distant metastases. Distal gastrectomy was performed for gastric cancer with Billroth Ⅰ reconstruction. He had no complications and was discharged on postoperative day 11. The pathological Stage was pT2N0M0, pStage ⅠB, and he underwent no adjuvant chemotherapy. Four months postoperatively, serum CA19-9, AFP, and PIVKA-Ⅱ were elevated, and CT revealed multiple liver tumors. A liver biopsy was performed for the definitive diagnosis. The patient was diagnosed with liver metastases from gastric cancer. It is considered that AFP and PIVKA-Ⅱ were produced by the liver metastasis from gastric cancer. He received chemotherapy for liver metastasis and died 1 year after the recurrence.

[Outcomes of FOLFIRINOX as First-Line Treatment for Recurrent or Unresectable Pancreatic Cancer].

We retrospectively analyzed adverse effects(AEs), overall survival(OS), and progression-free survival(PFS)in 15 consecutive patients treated with FOLFIRINOX as the first-line treatment for recurrent or unresectable pancreatic ductal adenocarcinoma( PDAC)between February 2014 and December 2017 in our hospital. Eleven patients were treated for unresectable PDAC with distant metastases(UR-M), and 4 were treated for locally advanced unresectable PDAC(UR-LA). The median age was 56(range: 40-75)years. Nine patients were male, and 6 were female. The performance status was 0 or 1 in all patients. Tumors were located in the pancreas head in 8 cases and in the body-tail in 7 cases. Grade 5 AEs were observed in 1 case in which liver abscess causing sepsis resulted in mortality. The response rate was 20.0%, and the disease control rate was 66.7%. Two patients underwent conversion surgery after FOLFIRINOX treatment. Seven patients received a nab-paclitaxel plus gemcitabine regimen as second-line treatment. The median OS and PFS were 17.0 and 8.4 months, respectively, and the 1-year survival rate was 66.7%. FOLFIRINOX for recurrent and unresectable PDAC showed relatively good tumor control. However, strict attention is required for severe AEs. Conversion surgery might be effective in patients who are good responders even if they have metastatic disease.

Self-expanding metallic stent improves histopathologic edema compared with transanal drainage tube for malignant colorectal obstruction.

AIMS: To compare the usefulness of the self-expanding metallic stent (SEMS) with that of the transanal drainage tube (TDT) and emergency surgery after failure of decompression (ESFD) in patients with malignant colonic obstruction (MCO), and to evaluate post-decompression histopathologic changes. METHODS: From January 2010 to June 2015, 39 patients with MCO received SEMS, TDT, and ESFD. We evaluated the outcomes including success rates of placement, clinical outcomes after decompression, and histopathologic findings of the resected specimens. RESULTS: Technical success rates were 100% for SEMS and 78.9% for TDT. Clinical success rates were 100% for SEMS and 80.0% for TDT. Postoperative ileus was significantly less frequent after SEMS than after TDT (p = 0.014). Histopathologic edema grade was significantly lower for SEMS than for TDT and ESFD (p < 0.0001). There was no significant difference between edema grade and duration of decompression in the TDT group (p = 0.629), while all patients with SEMS were classified in a low edema grade (grade 0-2). The rate of stoma creation was significantly higher in patients with a high edema grade (grade 3) than in those with a low edema grade (grade 0-2) (p = 0.003). There was no microscopic perforation in any group. CONCLUSION: Significantly greater resolution of histopathologic edema was achieved after placement of SEMS than after placement of TDT. These findings provide an indication of favorable clinical outcomes of SEMS in comparison with TDT and ESFD. This article is protected by copyright. All rights reserved.

[A Case of Collision Tumor of Gastric Malignant Lymphoma and Gastric Cancer].

A 71-year-old man with anemia, weight loss, and loss of appetite was admitted. Ultrasound examination found thickening of the wall of the stomach. A type 3 gastric tumor was detected in the greater curvature of the gastric corpus via upper gastrointestinal endoscopy. Total gastrectomy, transverse colon resection, and Roux-en-Y anastomosis reconstruction was performed. In the postoperative pathological results, adenocarcinoma, tub2, and diffuse large B cell lymphoma collision was found. The patient underwent chemotherapy for malignant lymphoma and although it was a relatively advanced neoplasia, he is alive without a recurrence.

Prognostic classification of thyroid follicular cell tumors using Ki-67 labeling index: risk stratification of thyroid follicular cell carcinomas.

This review emphasizes that the so-called high-risk thyroid carcinoma is not a distinct tumor entity, but a group of tumors with different histologies. High-grade histological features, such as tumor necrosis, increased mitoses, and nuclear pleomorphism, together with high Ki-67 labeling index (more than 10%), are good indicators of high-risk thyroid carcinoma and suggest a possible risk for anaplastic transformation. This review proposes the stratification of patients with thyroid carcinoma into low-, moderate-, and high-risk groups based on Ki-67 labeling index, which should be useful for the clinical management of patients, even after initial surgery. Currently, both the aggressive variant of papillary carcinoma and poorly differentiated carcinoma are aggressively treated by a completion of total thyroidectomy with prophylactic lymph node dissection followed by radioactive iodine treatment. Therefore, patients with moderate-risk or high-risk thyroid carcinoma based on Ki-67 labeling index should also be considered candidates for this treatment strategy.

[A Case in Which Eating Ability Was Restored after Chemotherapy for Gastric Metastasis Following Colon Cancer Resection].

We report here a rare case of gastric metastasis after resection ofa transverse colon cancer in which eating ability was restored following mFOLFOX6 (folinic acid plus fluorouracil plus oxaliplatin) plus cetuximab (Cet) chemotherapy. A 56-year-old man with chief complaints of constipation and abdominal fullness was referred to our hospital. In February 2013, he was diagnosed with transverse colon cancer via enema and colonoscopy. We performed transverse colon cancer resection followed by a 6-month course of capecitabine chemotherapy. In July 2014, the patient's serum carcinoembryonic antigen level increased, in October, he was again referred to our hospital with complaints of appetite loss and vomiting. He was diagnosed with multiple lymph node and gastric metastases via ultrasonography, computed tomography, and endoscopy, as well as multiple lung metastases via computed tomography. As the gastric metastases and vomiting rendered him unable to eat, a nasogastric tube was inserted and was administered mFOLFOX6 plus Cet chemotherapy. After 2 courses of chemotherapy his ability to eat was restored. As of March 2015, the patient remains alive following 12 courses of chemotherapy.

Loss of cellular cohesion in cytology composes a special subgroup of breast tumors - analysis of 37 cases.

OBJECTIVE: We analyzed smears by fine needle aspiration (FNA) from 37 cases that displayed numerous dissociated cells and correlated the results with histological findings. STUDY DESIGN: Between 1996 and 2005, 1,583 patients underwent breast FNA and resection. Loss of cellular cohesion was observed in 37 of these cases. RESULTS: From the cytological findings, we classified cases into 3 groups according to cell size and shape. Type A: numerous isolated spindle cells with a necrotic background. Four cases were classified into this group (3 cases of intraductal papilloma and 1 case of adenomyoepithelioma). Type B: lymphocytes and large isolated cells such as medullary carcinoma. Five cases were classified into this group [1 case of classic medullary carcinoma, 1 case of ductal carcinoma in situ (DCIS) and 3 cases of invasive carcinoma of no special type (NST)]. Type C: numerous uniform small round cells. Twenty-eight cases were classified into this group (2 cases of lobular carcinoma, 1 case of DCIS, 22 cases of invasive carcinoma NST, and 3 cases of solid papillary carcinoma). CONCLUSION: Numerous isolated cells are sometimes seen in both benign and malignant cytology.

Dense-type crypt opening seen on magnifying endoscopy with narrow-band imaging is a feature of gastric adenoma.

BACKGROUND: Magnifying endoscopy with narrow-band imaging (ME-NBI) can visualize crypt openings (CO) as slit-like structures in gastric epithelial neoplasia. Visualization of numerous CO is characteristic of low-grade adenoma (LGA). The aim of the present study was to investigate whether visualization of CO by ME-NBI is useful for discriminating between LGA and early gastric cancer (EGC). PATIENTS AND METHODS: Fifty-one superficial elevated-type gastric neoplasias (10 LGA and 41 EGC) were retrospectively evaluated. The presence of CO and the number of CO were evaluated in endoscopic photos obtained at high-power endoscopic magnification by ME-NBI. The optimal cut-off value for the number of CO visualized to discriminate between LGA and EGC was determined by receiver operating characteristic curve analysis. RESULTS: The mean number of CO visualized was significantly larger in the LGA group than in the EGC group (31.2, 95% confidence interval [CI] 16.3-46.1 vs 6.3, 95% CI 3.6-9.0; P < 0.001). When the cut-off for the number of CO visualized was set at 20, the sensitivity, specificity, and accuracy of dense-type CO for discriminating between LGA and EGC were 90.0%, 87.8%, and 88.2%, respectively. CONCLUSION: Determining the number of CO visualized in superficial elevated-type gastric neoplasias by ME-NBI appears to be a useful method for discriminating between LGA and EGC.

Clinical characteristics of collagenous colitis with linear ulcerations.

BACKGROUND: The relationship between the thickness of subepithelial collagen bands (CB) and the development of linear ulcerations (LU) in collagenous colitis (CC) remains unclear. The aim of the present study was to compare the clinical and pathological features, including the thickness of CB, in CC patients with and without LU. PATIENTS AND METHODS: Twenty-five patients with CC diagnosed by pathological examination of biopsy specimens were analyzed. Eleven patients with LU (LU group) and 14 patients without LU (non-LU group) were compared. RESULTS: Ten patients in the LU group and seven in the non-LU group were taking lansoprazole (P = 0.038). Seven patients in the LU group and one in the non-LU group were taking non-steroidal anti-inflammatory drugs (NSAIDs) (P = 0.004). All LU were locatedin the transverse or left colon. Patients in the LU group were older than those in the non-LU group (P = 0.015). CB were significantly thicker in the LU group than in the non-LU group (mean ± SD, 40 ± 21 µm vs 20 ± 11 µm, P = 0.004). Multivariate analysis showed that NSAIDs use (odds ratio, 19.236; 95% confidence interval, 1.341-275.869) and CB thickness (odds ratio, 0.893; 95% confidence interval, 0.804-0.999) were independently associated with the development of LU. CONCLUSION: Use of lansoprazole and NSAIDs, thick CB, and advanced age are associated with the development of LU in CC patients.

[A case of long-term survival following chemotherapy after laparoscopic resection of sigmoid colon cancer with multiple liver metastases].

We report a rare case of long -term survival after laparoscopic resection of sigmoid colon cancer with multiple liver metastases, followed by 5-fluorouracil Leucovorin irinotecan with bevacizumab (FOLFIRI+Bev) chemotherapy. A 61-year-old woman was referred to our hospital with a principal complaint of bloody stools. She was diagnosed with sigmoid colon cancer by colonoscopy and multiple liver metastases by ultrasonography. In October 2008, we performed laparoscopic resection of the sigmoid colon cancer with multiple liver metastases, followed by 4 courses of modified 5-fluorouracil Leucovorin oxaliplatin ( mFOLFOX6) chemotherapy. In February 2009, abdominal ultrasonography showed progressive disease, and as a result the patient was administered 73 courses of FOLFIRI +Bev chemotherapy. As of March 2014, the patient has survived for more than 5 years following treatment, but still has liver metastases. The possibility of resecting multiple liver metastases from colorectal cancer should be considered, and in some cases, chemotherapy may enhance survival.

[Three cases of hepatocellular carcinoma with nodules showing different signal intensities in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI].

We report three cases of resected hepatocellular carcinomas with nodules showing different signal intensities in the hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRI (EOB-MRI). One case involved a nodule-in-nodule type hepatocellular carcinoma that showed high signal intensity for the outer tumor and low intensity for the inner tumor in the hepatobiliary phase of EOB-MRI. The inner tumor was more dedifferentiated than the outer. The other two cases involved similar nodules, which showed different signal intensities in the hepatobiliary phase of EOB-MRI. In all three cases, the expression of OATP8 showed good correlation with high signal intensity in the hepatobiliary phase of EOB-MRI, whereas MRP2, MRP3, or both were also highly expressed. However, in the two nodules showing low intensities, the expression of one excreting transporter was independently high even though that of OATP8 was not high. The expression of excreting transporters is usually characterized by passive correspondence to OATP8 expression levels; nevertheless, it sometimes shows expression independent of OATP8.

Endometrioid adenocarcinoma arising from inguinal endometriosis during follow-up for gastric cancer surgery: a case report and literature review.

Malignant transformation of inguinal endometriosis is rare. A 56-year-old woman underwent surgery for advanced gastric cancer 5 years ago and received postoperative adjuvant chemotherapy. She had no recurrence since then. However, 5 years after surgery, contrast-enhanced computed tomography (CT) showed a mass in the right inguinal region suspected to be a hydrocele of the canal of Nuck, with a blood test showing a slightly elevated CA19-9 level (63.0 U/mL). Six months later, CT showed an enlarged mass in the right inguinal region and inflammation in the surrounding area. In addition, both inguinal lymph nodes and those in the right iliac artery area were enlarged, suggesting the possibility of malignancy. For diagnostic purposes, a right inguinal mass was excised. Histopathological examination revealed that it was endometrioid adenocarcinoma with ectopic endometriois as the origin. The differential diagnoses for inguinal masses in women include an inguinal hernia, hydrocele of the canal of Nuck, ectopic endometriosis, lymphoma, and metastatic malignancy. The presence of a primary malignancy in the inguinal region is sporadic but must be differentiated. This is the first case of malignant transformation of inguinal endometriosis developed during postoperative follow-up of another cancer.