Ovarian Mesonephric-like Adenocarcinoma Recurring With a Rhabdomyosarcoma Component: A Case Report.

Mesonephric-like adenocarcinoma (MLA) has recently been described as a tumor of the endometrium or ovaries, which, morphologically and immunohistochemically, resembles mesonephric adenocarcinoma arising mostly in the uterine cervix. Herein, we report, to our knowledge, the first case of ovarian MLA that developed into an extremely rapidly growing recurrent mesonephric-like carcinosarcoma, as confirmed by a genomic profiling test. A 51-year-old woman underwent chemotherapy with complete debulking surgery for ovarian carcinoma. Pathologically, the patient was diagnosed with stage IVB ovarian MLA. Subsequent to 15 months of complete remission, an enhanced computed tomography scan revealed a solid tumor of 10 cm diameter in the abdominal cavity. Secondary surgery was terminated with a 2 cm 2 tumor biopsy specimen collection considering perioperative complications. Histologically, the tumor consisted of short spindle cells, and immunohistochemical staining revealed a rhabdomyosarcomatous profile without an epithelial component. Despite treatment for the sarcoma, she died 3 months after the detection of the tumor. The genomic profiling of the primary ovarian carcinoma and secondary resected tumor biopsy specimens revealed an identical KRAS mutation in both. Therefore, we concluded that the ovarian MLA recurred with a rhabdomyosarcoma component.

Clinical characteristics and prognostic factors of endometrial stromal sarcoma and undifferentiated uterine sarcoma confirmed by central pathologic review: A multi-institutional retrospective study from the Japanese Clinical Oncology Group.

OBJECTIVES: Low-grade and high-grade endometrial stromal sarcomas (LGESS and HGESS) and undifferentiated uterine sarcomas (UUS) are rare tumors whose pathological classification and staging system have changed recently. These tumors are reported to contain fusion genes. We aimed to clarify the genetic background, clinical features, prognostic factors, and optimal therapy of these tumors using a new classification and staging system. METHODS: We analyzed the clinical features and prognostic information of 72 patients with LGESS, 25 with HGESS, and 16 with UUS using central pathological review. Estrogen and progesterone receptors (PgRs) were examined by immunohistochemistry. JAZF1-SUZ12 and YWHAE-NUTM2A/B gene fusions were tested using real-time polymerase chain reaction. RESULTS: The 5-year overall survival (OS) rates of LGESS, HGESS, and UUS were 94%, 53%, and 25%, respectively. In LGESS, stage IV, incomplete surgery, and absence of PgR were associated with poor OS. The presence of JAZF1-SUZ12 fusion gene was not associated with OS. In HGESS, the relationship between stage and prognosis was unclear. None of the 3 patients with YWHAE-NUTM2A/B fusion gene died during follow-up. Adjuvant chemotherapy was associated with a favorable OS. Incomplete resection of UUS was associated with poor OS; however, residual tumors frequently occurred. Although most patients underwent adjuvant chemotherapy, their prognosis was extremely poor even in stage I disease. CONCLUSIONS: Prognosis of LGESS is generally good; however, stage IV, incomplete surgery, and PgR-negative tumors are associated with poor prognosis. Adjuvant chemotherapy may be useful for HGESS. Prognosis of UUS is extremely poor, even with adjuvant chemotherapy.

Intraosseous Lipoma of the Calvaria in the Early Stage Resembling Normal Fatty Marrow.

Intraosseous lipoma (IOL) is a benign bone tumor that usually arises from the lower limb and rarely arises from the skull. Radiological diagnosis of a typical case is not problematic due to its characteristic calcification and marginal sclerosis. Here, we report a case of calvarial IOL in the early stage lacking conventional radiopathological features. The patient is a 7-year-old girl who presented with a slow-growing protuberance on the vertex of the head. Computed tomography displayed a low-density mass without calcification that was continuous with the surrounding diploe. The mass was resected piece by piece for diagnostic and cosmetic reasons. Histologically, the specimen consisted of bony trabeculae and intertrabecular adipose tissue, which resembled normal fatty marrow. However, adipose tissue was considered neoplastic since it lacked hematopoietic elements. The final diagnosis of IOL was made by radiopathological correlation. This case suggests that IOL should be included in the differential diagnosis of diploic expansion, even if calcification is absent. The histology of an early-stage IOL resembles normal fatty marrow, but recognizing the absence of hematopoietic elements aids the diagnosis. Also, our literature review indicates that such cases are likely to be encountered in the calvaria than cranial base.

Discrepancies in pathological diagnosis of endometrial stromal sarcoma: a multi-institutional retrospective study from the Japanese clinical oncology group.

Endometrial stromal sarcoma (ESS) is a rare uterine malignancy that requires accurate pathological diagnosis for proper treatment. This study aimed to clarify the discrepancies in the pathological diagnosis of ESS and obtain practical clues to improve diagnostic accuracy. Between 2002 and 2015, 148 patients with low-grade ESS (LGESS), high-grade ESS (HGESS), undifferentiated endometrial sarcoma (UES), or undifferentiated uterine sarcoma (UUS) diagnosed at 31 institutions were included. We performed immunohistochemistry, real-time polymerase chain reaction for JAZF1-SUZ12 and YWHAE-NUTM2A/B, and break-apart fluorescent in situ hybridization for JAZF1, PHF1, and YWHAE. Central pathology review (CPR) was performed by six pathologists. After CPR, LGESS, HGESS, UES/UUS, and other diagnoses were confirmed in 72, 25, 16, and 31 cases, respectively. Diagnostic discrepancies were observed in 19.6% (18/92) of LGESS and 34% (18/53) of HGESS or UUS/UES. Adenosarcomas, endometrial carcinomas, carcinosarcomas, and leiomyosarcomas were common diagnostic pitfalls. JAZF1-SUZ12 transcript, PHF1 split signal, and YWHAE-NUTM2A/B transcript were mutually exclusively detected in 23 LGESS, 3 LGESS, and 1 LGESS plus 3 HGESS, respectively. JAZF1-SUZ12 and YWHAE-NUTM2A/B transcripts were detected only in cases with CPR diagnosis of LGESS or HGESS. The CPR diagnosis of LGESS, HGESS, and UUS was a significant prognosticator, and patients with LGESS depicted a favorable prognosis, while those with UUS showed the worst prognosis. Pathological diagnosis of ESS is often challenging and certain tumors should be carefully considered. The accurate pathological diagnosis with the aid of molecular testing is essential for prognostic prediction and treatment selection.

A collision tumor of solitary fibrous tumor/hemangiopericytoma and meningioma: A case report with literature review.

An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry.

Dysgerminoma with Estrogen-Producing Functioning Stroma Presenting Precocious Puberty.

Dysgerminoma is a malignant ovarian germ cell tumor, and unlike sex-cord stromal tumors, endocrine manifestation is considered rare. Here, we report the first case of dysgerminoma presenting precocious puberty. The patient is a 7-year-old girl who presented with a breast development in Tanner stage 3. Serum estradiol (E2) was markedly elevated while luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were suppressed below the detection limit. Microscopically, the right ovarian mass displayed nests of large polygonal cells and fibrous septa which were focally concentrated by theca-like plump spindle cells. Immunohistochemistry revealed that the spindle cells expressed various steroidogenic enzymes involved in estrogen biosynthesis including P450 aromatase. The tumor was diagnosed with pure dysgerminoma with estrogen-producing functioning stroma. After the operation, serum E2 declined below the detection limit; LH and FSH returned within the normal range. This case demonstrates that even a conventional dysgerminoma can present endocrine manifestation through functioning stroma.

Clinical manifestations of placental mesenchymal dysplasia in Japan: A multicenter case series.

AIM: This study aimed to evaluate the clinical features and pregnancy outcomes of placental mesenchymal dysplasia (PMD) in Japan. METHODS: We requested detailed clinical information and placental tissue of PMD cases in 2000-2018 from Japanese facilities with departments of obstetrics and gynecology and analyzed the pregnancy course and neonatal outcomes. RESULTS: We collected 49 cases of PMD. Of 18 patients with measured maternal serum alpha-fetoprotein (MSAFP) levels, 15 (83.3%) had elevated levels. Maternal serum human chorionic gonadotropin (MShCG) levels were transiently elevated in five (17.8%) of 28 patients. Forty-seven patients continued their pregnancies. All pregnancies were singleton and 40 (85.1%) were associated with adverse events including fetal growth restriction (FGR), threatened premature delivery, fetal demise, and hypertensive disorder of pregnancy in 34 (72.3%), 14 (29.8%), eight (17.0%), and six (12.8%) patients, respectively. Of 47 infants, there were eight stillbirths. There were 40 (85.1%) female infants, and eight (17.0%) had Beckwith-Wiedemann syndrome. Of 39 live births, 23 (59.0%) were associated with premature induction of labor or cesarean section for obstetric indications related to FGR. Eighteen (46.2%) neonates had complications. PMD-affected placentas were pathologically heterogeneous in both grossly PMD-affected and non-affected areas. CONCLUSIONS: Our study included the largest number of PMD cases with detailed clinical information. PMD is a high-risk condition for both the mother and the child. Elevated MSAFP levels with normal MShCG levels indicate PMD. Conventional perinatal management of FGR in Japan might be effective in reducing the fetal mortality rate.

Primary Central Nervous System Lymphoma with Peripheral Nerve Involvement: Case Report.

A 50-year-old man presented with dizziness and hearing disturbance in the right ear. Magnetic resonance imaging (MRI) revealed a well-enhanced mass lesion in the right cerebellopontine (CP) angle that appeared to originate in the cerebellum. A surgical specimen obtained at the subtotal resection with craniotomy revealed a diffuse large B-cell lymphoma (DLBCL). During the three courses of chemotherapy with high-dose methotrexate (MTX) with leucovorin rescue, he developed a right abducens palsy, left oculomotor palsy, left facial palsy, right trigeminal sensory disturbance, and paraparesis. Although the brain MRI showed that the CP angle tumor had disappeared completely following chemotherapy, enhanced lesions along the cauda equina were detected on a lumbar spine MRI. FDG-PET (18 F-fluorodeoxyglucose positron emission tomography) revealed multiple high-uptake abnormalities in the cranial nerves and spinal nerves. Tumor cells were found in the cerebrospinal fluid specimen from a lumbar puncture. Craniospinal irradiation was performed, including all the abnormal FDG high-uptake areas, and was effective in relieving the patient's symptoms. On FDG-PET, the high-uptake abnormalities in the peripheral nerves disappeared. However, five weeks after the irradiation, he developed right trigeminal sensory disturbance, hoarseness, dysphagia, and right arm pain. FDG-PET disclosed multiple high-uptake abnormalities in more peripheral portions of the cranial nerves and spinal nerves. Chemotherapy with rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine (Oncovin®), and prednisolone (R-CHOP) was then resorted to which mitigated his symptoms. On follow-up FDG-PET, the high-uptake abnormalities in the peripheral nerves disappeared again.

A multi-center retrospective study of neuroendocrine tumors of the uterine cervix: Prognosis according to the new 2018 staging system, comparing outcomes for different chemotherapeutic regimens and histopathological subtypes.

OBJECTIVE: To analyze the clinical behavior of neuroendocrine tumors (NETs) of the uterine cervix, we conducted a multicenter, retrospective study of 193 patients. METHODS: We evaluated the prognosis of NETs according to the new International Federation of Gynecology and Obstetrics (FIGO) staging system, compared the clinical response to different chemotherapy regimens, and compared different histological subtypes of NETS. RESULTS: Diagnoses of the subjects were atypical carcinoid tumor (ACT, n = 37), small cell neuroendocrine carcinoma (SCNEC, n = 126), large cell neuroendocrine carcinoma (LCNEC, n = 22), and NET, not elsewhere classified (n = 8), according to central pathological review. According to FIGO 2018, 69, 17, 74, and 33 patients were at stage I, II, III, or IV, respectively. Five-year survival was 64.5%, 50.1%, 30.2%, and 3.4% for patients at stage I, II, III and IV. About 40% of patients with stage IIIC1 survived >5 years. On multivariate analyses, locally-advanced disease, para-aortic node metastasis, distant metastasis, and <4 cycles of chemotherapy were associated with poor survival. Histological subtype and pelvic node metastasis had no prognostic significance. Response rates to etoposide-platinum (EP) or irinotecan-platinum (CPT-P) regimens were 43.8% (28/64), but only 12.9% to a taxane-platinum (TC) regimen (4/31). The response rate for ACT was 8.7% (2/23), significantly less than the 36.6% for high-grade neuroendocrine carcinomas (HGNEC: both SCNEC and LCNEC, 41/111). CONCLUSIONS: Locally-advanced, extra-pelvic disease and insufficient chemotherapy were independent prognostic factors for cervical NET. HGNEC showed good responses to EP or CPT-P but not TC. Chemotherapy was less effective for ACT, which had a prognosis identical to HGNEC.

Superficial Myofibroblastoma in the Vulva Mimicking Aggressive Angiomyxoma: A Case Report and Review of the Literature.

BACKGROUND: Superficial myofibroblastoma (SMF) is a very rare benign mesenchymal tumor in the female lower genital tract. Only 46 cases have been reported in the English language literature, among which only 7 cases arose in the vulva. Sometimes SMF histologically mimics aggressive angiomyxoma (AA) in which massive myxoid change in stroma is characteristic. We herein report a case of vulvar SMF with prominent myxoid stroma and review the literature with the emphasis on the differential diagnosis of SMF and AA. CASE PRESENTATION: a 37-year-old woman presented with a painless mass in the vulva. Magnetic resonance imaging (MRI) showed a well-circumscribed 7 cm mass in the subcutis of the vulva. The tumor was resected. Histopathologically, the tumor was characterized by sparsely populated spindle-shaped cells in the fibromyxoid stroma. Thin-walled blood vessels were detected. Mitoses or pleomorphism was not found. Tumor cells were positive for vimentin, ER, PgR, and desmin. Some cells were positive for alpha-SMA and CD34. All cells were negative for S100 protein. CONCLUSIONS: because SMF and AA show different clinical prognoses, distinguishing SMF from AA is important. However, SMF may share many common histological features with AA: superficial localization (above fascia), sharp borderline from adjacent tissue, expansive growth pattern; a specific vascular pattern will lead to an accurate diagnosis of SMF. Familiarization with the histological characteristics of the two entities will help to make a prognostic prediction.

Coexistence of Cervical Leiomyosarcoma and Gastric-Type Adenocarcinoma In Situ with Extensive Extension to the Endometrium and Fallopian Tube.

Cervical leiomyosarcoma is known to be rare from the previous reviews of a large number of malignant cervical tumors. The patient was a 66-year-old woman with irregular vaginal bleeding. She underwent modified radical hysterectomy and bilateral salpingooophorectomy. Histopathologically, we diagnosed the coexistence of uterine cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ with endometrial lesions that had continuous and skip patterns and fallopian tubal lesions with a partial lesion. To the best of our knowledge, cases of synchronous leiomyosarcoma and cancers have not often been reported; only two cases of synchronous cervical leiomyosarcoma and cervical squamous cell carcinoma have been published. This case is the first presentation of coincidental primary cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ. Additionally, we considered cervical gastric-type adenocarcinoma in situ with continuous lesions on the endometrium and skip lesions on the left fallopian tube.

Prognostic factors and optimal therapy for stages I-II neuroendocrine carcinomas of the uterine cervix: A multi-center retrospective study.

PURPOSE: We aimed to determine appropriate treatment guidelines for patients with stages I-II high-grade neuroendocrine carcinomas (HGNEC) of the uterine cervix in a multicenter retrospective study. PATIENTS AND METHODS: We reviewed the clinicopathological features and prognoses of 93 patients with HGNEC of International Federation of Gynecology and Obstetrics (FIGO) stages I and II. All patients were diagnosed with HGNEC by central pathological review. RESULTS: The median overall survival (OS) and disease-free survival (DFS) were 111.3months and 47.4months, respectively. Eighty-eight patients underwent radical surgery, and five had definitive radiotherapy. The hazard ratio (HR) for death after definitive radiotherapy to death after radical surgery was 4.74 (95% confidence interval [CI], 1.01-15.90). Of the surgery group, 18 received neoadjuvant chemotherapy. Pathological prognostic factors and optimal adjuvant therapies were evaluated for the 70 patients. Forty-one patients received adjuvant chemotherapy with etoposide-platinum (EP) or irinotecan-platinum (CPT-P). Multivariate analyses identified the invasion of lymphovascular spaces as a significant prognostic factor for both OS and DFS. Pelvic lymph node metastasis was also a prognostic factor for DFS. Adjuvant chemotherapy with an EP or CPT-P regimen appeared to improve DFS (HR=0.27, 95% CI, 0.10-0.69). A trend toward improved OS was also observed, but was not statistically significant (HR=0.39, 95% CI, 0.15-1.01). CONCLUSION: Radical surgery followed by adjuvant chemotherapy with an EP or CPT-P regimen was optimal treatment for stages I and II HGNEC of the uterine cervix.

One case that developed bile duct cancer all over the progress of repeated cholangitis.

A 65-year-old man was referred to our department due to repeated episodes of cholangitis in the past five years. Endoscopic retrograde cholangiopancreatography was performed, and a stricture of the lower bile duct was detected. At a later date, an irregular mucosa of the bile duct was confirmed using nasal endoscopy. Based on the biopsy results, the patient was diagnosed with bile duct cancer and subsequently underwent surgery. Postoperative histopathology did not show lymph node metastasis, and the condition was determined to be early-stage bile duct cancer. In the present case, it was presumed that the cancer had developed due to chronic cholangitis. Therefore, in patients with repeated episodes of cholangitis, attention should be focused on the possible and concomitant development of cancer.

Shiga Toxin Subtypes and Virulence Genes in Escherichia coli Isolated from Cattle.

Subtypes of stx1 and stx2 in 45 Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle were investigated by PCR. Only subtype stx1a was detected among all the stx1-positive strains. The major stx2 subtype was stx2a followed by stx2d, stx2c, stx2b, and stx2g in decreasing order of frequency. stx2c was found in strains of serotypes O157 and O174. stx2d was found in 11 strains. These strains were confirmed by DNA sequencing to carry both the activatable tail and the END motif; all were eae-negative, and 3 contained stx2d as the only stx. stx2g was found in 2 strains in association with stx2a, estA1, and astA. In addition, 7 hybrid strains of shigatoxigenic and enterotoxigenic E. coli (STEC/ETEC) were found to harbor one or both of stx1a and stx2a (stx1a/stx2a) and estA1. Among 27 serotypes of STEC strains isolated from cattle, O157:H7 and O109:H- strains were eae-positive. Other putative adhesin genes, such as saa, iha, espP, and lpfAO113 were detected in more than 12 serotypes.

Concurrent high-grade serous carcinoma and borderline tumor demonstrating different chemo-sensitivity.

Ovarian high-grade serous adenocarcinoma responds well to regular platinum/taxane chemotherapy, while borderline tumor survives and demonstrates persistent disease. A 69-year-old Japanese woman was suspected for having advanced ovarian carcinoma. MRI showed cystic tumor containing solid component of the right adnexal region with massive ascites and peritoneal dissemination. Serum CA125 was elevated to 203 µ/ml; however, no remote metastases were detected. Laparotomy revealed that peritoneal carcinomatosis spreads out to omentum and subphrenic area. Omentum was partially removed with big tumor nodules that histologically demonstrated the high-grade serous adenocarcinoma with positive ascites cytology. After 6 cycles of postoperative chemotherapy with docetaxel and carboplatin, she received second surgery where the known residual bilateral adnexa and all of the persistent tumors were perfectly resected. Pathological examination of the tumor revealed serous borderline tumor with microinvasion and no evidence of residual high-grade serous carcinoma with negative ascites cytology. This is the extremely rare case of concurrent high-grade serous carcinoma and borderline tumor demonstrating differential chemo-sensitivity.

Stepwise increase of MIB-1 index in frequently relapsed malignant peritoneal mesothelioma.

We identified the stepwise increase of MIB-1 index in a long-surviving malignant peritoneal mesothelioma (MPM) patient with a history of frequent relapse. A 29-year-old Japanese woman showed upper abdominal induration with adnexal tumor. Imaging study with biochemical analyses strongly suggested peritoneal tumor. On primary surgery, all tumors were resected completely without any residual tumor. Histologically, the tumor was diagnosed as MPM, for which she received adjuvant chemotherapy containing platinum agent. Two years later, the tumor relapsed in her pelvic cavity, but was resected completely with hysterectomy and salpingo-oophorectomy. Histologically, the tumor was diagnosed as MPM relapse. She underwent intraperitoneal chemotherapy with cisplatin that achieved progression-free survival of 5 years. However, relapse was detected again in pelvic cavity without any dissemination in upper abdominal cavity. The tumors were completely removed and were revealed to be compatible with MPM. She received gemcitabine and carboplatin chemotherapy. However, 2 years later, the tumor relapsed again in left upper abdominal cavity, for which she wouldn't receive 4th treatment. To investigate the longevity of this patient in association with the histologic findings, the MIB-1 index was examined in the primary and relapse tumors. The rate of MIB-1 index positive cells was calculated by counting 500 cells. MIB-1 indices were 4.2 ± 1.1 (mean ± SE), 11.8 ± 2.3, and 37.3 ± 2.5 in primary, 1st- and 2nd-relapsed tumor, respectively, demonstrating stepwise increase of MIB-1 expression over the surviving time of more than 9 years. Increase in MIB-1 index was not associated with mitotic index but may be indicating drug sensitivity, resulting in >2-year progression-free interval in each relapse.

Multilocular cystic leiomyoma of the anterolateral abdominal wall: A case report and literature review.

RATIONALE: Leiomyomas arising from the anterolateral abdominal wall are uncommon, and their pathogenesis remains unknown. We present the 15th case of such a tumor, having this unique tumor morphology, followed by a detailed discussion on disease pathogenesis. PATIENT CONCERNS: A 48-year-old, asymptomatic perimenopausal, multiparous Japanese woman presented with a left-sided pelvic mass. She had no history of previous surgeries or uterine leiomyomas. Although a transabdominal ultrasonogram raised suspicions of an ovarian tumor, a transvaginal ultrasonogram confirmed normal ovaries. Radiological images showed a multilocular cystic mass with enhanced solid lesions connected to the uterus. Retrospective radiological evaluation showed that the mass was largely connected to the peritoneum of the anterolateral abdominal wall. INTERVENTIONS: Intraoperatively, the mass appeared as a dome-like protrusion from the left lower quadrant of the abdominal wall, without connection to the uterus, ovaries, or the left round ligament. No other peritoneal masses were seen. The mass was easily enucleated from the abdominal wall. Pathology confirmed that the mass was a leiomyoma with hydropic and myxoid degeneration. No striated muscle tissues were noted between the tumor and resection margin, but a thin smooth muscle layer, positive for hormone receptors, was present at the periphery, suggesting the origin of the tumor. LESSONS: Benign leiomyomas of the anterolateral abdominal wall likely originate from Müllerian-like smooth muscle remnants in this region. They should be considered in the differential diagnosis of solid and cystic masses and be distinguished from uterine and ovarian masses on imaging to avoid unnecessary organ resection.

A subserosal, pedunculated, multilocular uterine leiomyoma with ovarian tumor-like morphology and histological architecture of adenomatoid tumors: a case report and review of the literature.

BACKGROUND: Uterine leiomyomas are common uterine tumors, and typical cases of leiomyoma are easily diagnosed by imaging study. However, uterine leiomyomas are often altered by degenerative changes, which can cause difficulty and confusion in their clinical diagnosis. We describe the 17th reported case of a uterine leiomyoma clinically diagnosed as an ovarian tumor; however, the present case shows the most detailed radiological evaluation, including contrast-enhanced magnetic resonance imaging. We first show that a uterine leiomyoma can histologically mimic an adenomatoid tumor. CASE PRESENTATION: A 47-year-old premenopausal, nulliparous Japanese woman with a history of type 2 diabetes mellitus, hypertension, and hyperlipidemia had lower abdominal pain. Ultrasonography confirmed a 6-cm mass in the right-sided space of the pelvic cavity. Magnetic resonance imaging evaluation showed that a multilocular mass was present near the uterus, and a mucinous ovarian tumor was considered. Emergency surgery due to acute abdomen was performed under the diagnosis of pedicle torsion of the ovarian tumor. During surgery, a pedunculated uterine mass without stalk torsion was seen. The mass grossly contained serous and hemorrhagic fluids in the cavities, and pathology examination confirmed that the mass was a leiomyoma with hydropic and cystic degeneration. Anastomosing thin cord-like arrangements of the leiomyoma cells mimicked the architecture of adenomatoid tumors. The tumor cells were positive for the microphthalmia transcription factor but negative for other melanoma markers. Three days postoperatively, she was discharged without sequelae. CONCLUSIONS: Marked intratumoral deposition of fluids may induce the multilocular morphology of a tumor, and the cellular arrangement of the tumor cells with hydropic degeneration mimicked an adenomatoid tumor in this case. Clinicians need to be aware that a subserosal leiomyoma with cystic and hydropic degeneration can mimic an ovarian tumor, and pathologists should be aware that such leiomyomas can mimic adenomatoid tumors. Additionally, perivascular epithelioid cell tumors should not be diagnosed only based on its immunoreactivity for the microphthalmia transcription factor.

Malignant Struma Ovarii With a Predominant Component of Anaplastic Carcinoma.

Struma ovarii exhibiting malignant histology are uncommon, and aggressive clinical courses with initial extraovarian spread are even more rare. This report describes a case of malignant struma ovarii with a predominant anaplastic carcinoma component. A 65-yr-old, gravida 2, para 2, female presented with lower abdominal discomfort and pain. She had a 12×10×7.5 cm tumor in the right ovary. Intraoperative diagnosis was high-grade spindle cell tumor. Right salpingo-oophorectomy and hysterectomy were performed. Macroscopically, the tumor invading the right tube was a yellow-white solid mass with focal microcysts containing greenish liquid and focal calcification. The tumor was histologically characterized by a spindle cell and pleomorphic sarcomatous component, and a minor component of benign-looking thyroid tissue with ossification. Immunohistochemically, the sarcomatous component was focally positive for CAM 5.2, EMA, thyroid transcription factor-1, and thyroglobulin, indicating anaplastic carcinoma. The patient was treated with chemotherapy and is alive, yet with tumor, 25 mo after surgery. This is the first case of malignant struma ovarii with a predominant component of anaplastic carcinoma. This type of malignant struma ovarii may lead to diagnostic problems, and sampling and differential diagnosis among sarcomatous ovarian tumors are important for making the correct diagnoses.

Mitotically active cellular fibroma of the ovary: a case report and literature review.

BACKGROUND: The ovarian cellular fibrous tumor with mitotic figure >4 per 10 high power field without moderate to severe atypia is defined as mitotically active cellular fibroma according to the 2014 World Health Organization classification. As this category is new and rare now, we described here a case of MACF and reviewed the literature. CASE: We present a case of mitotically active cellular fibroma of the ovary with 10-year history that was treated with laparoscopic surgery. METHODS: We reviewed the relevant literature using PubMed search system and analyzed the previous cases. RESULTS: To date, only 5 cases of mitotically active cellular fibroma have been reported. Our patient is the first case of mitotically active cellular fibroma of the ovary treated with laparoscopic surgery. CONCLUSION: MACF of the ovary is a newly defined category and few cases have been reported, while prognostic factors have also not yet been fully characterized. Long-term clinical follow-up is necessary.