Development of immature ovarian teratoma after mature teratoma in a girl with familial ovarian teratoma:A case report

BACKGROUND Immature ovarian teratoma is a rare and aggressive neoplasm that affects young women.This report is the first to describe the development of immature teratoma after ovarian cystectomy for mature teratoma of the ovary in an adolescent female with a family history of ovarian teratoma.CASE SUMMARY A 16-year-old girl who had undergone bilateral ovarian cystectomy for mature teratomas 3 years ago showed bilateral adnexal tumors during her regular ultrasonography follow-up every 6 months.She received laparoscopic bilateral ovarian cystectomy,and final histopathology showed grade-1 immature teratoma of the left ovary and mature teratoma of the right ovary.Laparoscopic left salpingo-oophorectomy and staging procedures were performed again.Her mother,maternal aunt,and maternal grandmother had also received surgeries for mature ovarian teratomas.CONCLUSION It is important to have guidance on management of patient and family members with familial ovarian teratomas.

Adenocarcinoma of sigmoid colon with metastasis to an ovarian mature teratoma: A case report

BACKGROUND Colorectal cancer ranks third in global cancer-related mortality,often due to metastases to liver and lungs.Ovarian metastases are less common,accounting for 3.6%to 7.4%of cases.In contrast,mature ovarian teratomas are frequently benign.Tumor-to-tumor metastasis is a rare phenomenon,with a limited number of documented cases.Three cases of mature ovarian teratomas metastasizing from different cancers have been reported.This report focuses on a case of tumor-totumor metastasis from sigmoid colon adenocarcinoma to a mature ovarian teratoma.CASE SUMMARY A 41-year-old Taiwan residents woman with no known systemic diseases presented with lower back pain,which led to imaging revealing malignant lesions in the spine,pelvis,liver,and multiple lung metastases.She was diagnosed with sigmoid colon adenocarcinoma with metastases to the liver,lung,bone,and a left ovarian teratoma.Treatment involved radiotherapy and chemotherapy,resulting in regression of the primary tumor and stable lung and liver lesions.Due to abdominal symptoms,she underwent exploratory surgery,unveiling a mature teratoma in the left ovary with signs of metastatic adenocarcinoma.CONCLUSION Consider resecting mature ovarian teratomas with concurrent colorectal adenocarcinoma to prevent tumor-to-tumor metastasis.

Monodermal teratoma:Three case reports and review of literature

BACKGROUND The incidence of monodermal teratomas of the reproductive system is low,and most doctors lack adequate understanding,which can easily lead to missed diagnoses and/or misdiagnosis.Therefore,it is important to fully understand the clinical characteristics,diagnosis,differential diagnosis,and treatment of monodermal teratomas of the reproductive system.CASE SUMMARY Case 1:A 14-year-old boy was admitted to the hospital with a right testicular mass for 1 wk and underwent surgical resection.He was finally diagnosed with right testicular monodermal teratoma with no special postoperative discomfort.Case 2:A 40-year-old woman was admitted to the hospital for uterine abnormalities indicated by ultrasound 20 d prior and underwent laparoscopic surgery.She was finally diagnosed with a left ovarian monodermal teratoma with a satisfactory postoperative quality of life.Case 3:A 49-year-old woman was admitted to the hospital with a pelvic mass that was discovered on B-ultrasound a week prior and underwent laparoscopic resection of the left adnexa.She was finally diagnosed with left ovarian monodermal teratoma,and her postoperative quality of life was satisfactory.CONCLUSION Monodermal teratoma is a rare tumor whose clinical manifestations are primarily benign.Simple surgical resection of the tumor is effective.

Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report

BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life.

Prenatal ultrasound diagnosis of fetal maxillofacial teratoma:Two case reports

BACKGROUND Facial teratoma is a rare benign tumor that accounts for about 1.6%of all teratomas and can be diagnosed by prenatal ultrasound(US).The purpose of this report was to describe our experience with the diagnosis of fetal facial teratoma by prenatal US at second trimester to provide a reference for clinical diagnosis of fetal maxillofacial teratoma.CASE SUMMARY We present two cases of patients with abnormal fetal facial findings on US at second trimester of pregnancy in our department.Case 1 was a 31-year-old G3 P1+1 female,with US revealing a heterogeneous echogenicity of 32 mm×20 mm×31 mm on the fetal face,most of it located outside the oral cavity and filling the root of the oral cavity.Case 2 was a 29-year-old G1P0 female,with fetal head and neck US revealing a cystic-solid echo mass measuring 42 mm×33 mm×44 mm,the upper edge of the lesion reaching the palate and filling the oral cavity.The contours of the lesions were visualized using three-dimensional(3D)US imaging.Both patients decided to give up treatment.Biopsies of the lesions were performed after induction of labor,and diagnosed as maxillofacial teratoma.CONCLUSION Fetal maxillofacial teratomas can be diagnosed by US in early pregnancy,allowing parents to expedite treatment decisions.

Ruptured teratoma mimicking a pelvic inflammatory disease and ovarian malignancy:A case report

BACKGROUND We report a case of ruptured ovarian teratoma mimicking pelvic inflammatory disease(PID)and ovarian malignancy.The case indicates the need for reviewing the information on ovarian teratomas,as the symptoms are vague,and,therefore,diagnosis and treatment had to be structured accordingly.CASE SUMMARY A 60-year-old woman was admitted to the emergency department with acute lower abdominal pain.She experienced weight loss and increased abdominal girth.Pelvic ultrasound and computed tomography revealed a 14-cm pelvic tumor.Laboratory examination revealed leukocytosis(white blood cell count:12620/μL,segment:87.7%)and high levels of C-reactive protein(18.2 mg/dL).Elevated levels of the tumor marker cancer antigen 19-9(367.8 U/mL,normal value<35 U/mL)were also noted.Due to the impression of a ruptured tuboovarian abscess or a tumor with malignancy,she immediately underwent an exploratory laparotomy.A ruptured ovarian tumor with fat balls,hair strands,cartilage,and yellowish fluid was observed on the right side.Right salpingooophorectomy was performed.A pathological examination revealed a mature cystic teratoma.The patient recovered after surgery and was discharged on postoperative day three.No antibiotics were administered.CONCLUSION This case illustrates the differential diagnosis of an ovarian tumor.Therefore,surgery is the mainstay for treating a ruptured teratoma.

Giant teratoma with isolated intestinal duplication in adult: A case report and review of literature

BACKGROUND A combination of diseases is a rare phenomenon.Their clinical manifestations can vary,and the diagnosis can be challenging.Intestinal duplication is a rare congenital malformation,whereas retroperitoneal teratoma is a tumor in the retroperitoneal space,derived from the remaining embryonic tissue.There are relatively few clinical findings on adult retroperitoneal benign tumors.It is hard to believe that these two rare diseases can happen to the same person.CASE SUMMARY A 19-year-old woman complaining of abdominal pain with nausea and vomiting was admitted.Abdominal computed tomography angiography was suggested for invasive teratoma.Intraoperative exploration revealed that the giant teratoma was connected to an isolated intestinal tract in the retroperitoneum.The postoperative pathological examination revealed that mature giant teratoma was present with intestinal duplication.This was a rare intraoperative finding that was successfully treated surgically.CONCLUSION The clinical manifestations of intestinal duplication malformation are various,and difficult to diagnose before the operation.The possibility of intestinal replication should be considered when intraperitoneal cystic lesions are present.

Rare primary mature teratoma of the liver:A case report

BACKGROUND Primary liver teratoma is an extremely rare tumor usually affecting children under the age of 3 years.Specific signs of teratoma on ultrasound,computed tomography(CT)or magnetic resonance imaging are lacking,which makes morphology the only diagnostic tool.Misdiagnosis of a mature teratoma may lead to excessive liver resection,whereas misdiagnosis of an immature teratoma may result in spread,causing a life-threatening condition.Consequently,a careful tumor examination is important,and the rarest types of tumors must be accounted for.CASE SUMMARY We describe a 52 years old female who presented with a solid mass in the left liver lobe.Contrast-enhanced CT and magnetic resonance imaging(MRI)revealed a round,heterogeneous lesion containing a number of fluid areas and areas of calcification in the middle,and the provisional diagnosis was cholangiocarcinoma.The patient underwent resection of liver segment I.Immunohistochemistry analysis of the resected lesion indicated thyroid follicular epithelium;however,the thyroid gland was intact.10 years prior to presentation the patient underwent a surgery due to mature teratoma of the right ovary,nevertheless the tumor was benign and could not spread to the liver,in addition teratoma of the liver was also benign.This led to the final diagnosis of primary mature liver teratoma.CONCLUSION Primary hepatic teratoma,including heterotopia of the thyroid gland in the liver,is an extremely rare condition in adults that needs to be considered in the differential diagnosis of solid-cystic neoplasms in the liver and cholangiocarcinoma.This case adds to the limited literature on the patient presentation,clinical workup and management of liver teratomas.

Sacrococcygeal Teratoma

Key Facts Synonyms:Sacrococcygeal teratoma(SGT),germ cell tumor of coccyx Definition:Tumors containing hair,teeth,cartilage,and fat extending from the coccyx and potentially growing both internally and externally.

Serial imaging of human embryonic stem-cell engraftment and teratoma formation in live mouse models

Two new types of lentiviral vectors expressing a reporter transgene encoding either firefly luciferase （fLuc） for bioluminescence imaging or the HSV1 thymidine kinase （HSV1-TK） for radiopharmaceutical-based imaging were constructed to monitor human embryonic stem cell （hESC） engraftment and proliferation in live mice after trans- plantation. The constitutive expression of either transgene did not alter the properties of hESCs in the culture. We next monitored the formation of teratomas in SCID mice to test （1） whether the gene-modified hESCs maintain their developmental pluripotency, and （2） whether sustained reporter gene expression allows noninvasive, whole-body imaging of hESC derivatives in a live mouse model. We observed teratoma formation from both types of gene-modified cells as well as wild-type hESCs 2-4 months after inoculation. Using an optical imaging system, bioluminescence from the fLuc-transduced hESCs was easily detected in mice bearing teratomas long before palpable tumors could be detected. To develop a noninvasive imaging method more readily translatable to the clinic, we also utilized HSV1-TK and its specific substrate, 1-（2＇-deoxy-2＇-fluoro-β-D-arabinofuranosyl）-5-[^125I]iodouracil（[^125I]FIAU）, as a reporter/ probe pair. After systemic administration, [^125I]FIAU is phosphorylated only by the transgene-encoded HSV1-TK enzyme and retained within transduced （and transplanted） cells, allowing sensitive and quantitative imaging by single-photon emission computed tomography. Noninvasive imaging methods such as these may enable us to monitor the presence and distribution of transplanted human stem cells repetitively within live recipients over a long term through the expression of a reporter gene.

Primary gastric teratoma on the cardiac orifice in an adult

Gastric teratoma (GT) is a seldom seen congenital abnormality. GT always occurs in children. The greater curvature and posterior wall of the stomach are the most common sites involving GT. We diagnosed a case of GT located on the inferior wall of the cardiac orifice in a 20-year-old man. To the best of our knowledge, this is the first case of GT located on the wall of the cardiac orifice in an adult in the English literature. We report this unusual case as an addition to this rare disease usually found in children. Computed tomography combined with endoscopic ultrasonography can be selected to diagnose GT.

Duodenal mature teratoma causing partial intestinal obstruction:A first case report in an adult

BACKGROUND A teratoma is a germ cell tumor that is composed of tissue derived from two or three germ layers.Duodenal teratomas are extremely rare and have been exclusively reported in neonates and children.This is the third case of a teratoma primarily arising in the duodenum and the first case that occurred in an adult.CASE SUMMARY A 31-year-old male presented with clinical partial gut obstruction(epigastric pain,nausea,and vomiting).The physical examination showed a palpable illdefined mass on the left side of the abdomen.The computed tomography scan revealed a multiseptated cystic tumor at the retroperitoneal area.First,he underwent gastrojejunostomy to relieve the symptoms and was referred to a tertiary-care hospital.The second operation revealed a 10-cm solid-cystic mass originating from the third part of the duodenum and adhering to the abdominal aorta and pancreas.Segmental duodenectomy was performed.The pathological diagnosis was a mature cystic teratoma.The patient was asymptomatic at 5 mo after the operation.CONCLUSION Duodenal teratomas are extremely rare but should be included in the differential diagnosis in patients who present with intestinal obstruction.Radiological imaging is helpful to reach the preoperative diagnosis.Multidisciplinary team planning is essential to avoid injury to the adjacent organ in duodenal operation.

Ovarian teratoma related anti-N-methyl-D-aspartate receptor encephalitis:A case series and review of the literature

BACKGROUND Anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis is a rare but important complication of ovarian teratoma.Between July 2012 and December 2019,six patients with ovarian teratoma-associated anti-NMDAR encephalitis were enrolled in our hospital and their clinical characteristics,treatment,and follow-up were reviewed.We also conducted a systematic literature review of ovarian teratoma related anti-NMDAR encephalitis reports between January 2014 and December 2019.AIM To better understand anti-NMDAR encephalitis through literature review and patients enrolled in our hospital.METHODS The six patients enrolled in the study were those diagnosed with anti-NMDAR encephalitis.Their history,clinical manifestations,and medications were recorded and optimum treatment provided in addition to maintaining a record of the follow-ups.In addition,we also extensively surveyed the literature and provide summarized data from 155 published cases of anti-NMDAR encephalitis from 130 case reports.PubMed and Scopus were the sources of these publications and the time period covered was 6 years ranging from January 2014 through December 2019.RESULTS The six patients enrolled for this study presented with typical symptoms resulting in a diagnosis of ovarian teratoma induced anti-NMDAR encephalitis.Appropriate interventions led to a positive outcome in all the patients,with five of six patients reporting full recovery and the sixth patient recovering with a few deficits.No death was recorded.The literature survey comprising of 155 patients cases across 130 case reports of anti-NMDAR encephalitis clearly indicated an upward trend in the reports/diagnosis in China,particularly in the surveyed time from 2014 through 2019.The majority of patients(150/155)underwent surgical intervention resulting in positive outcome.No treatment intervention was mentioned for one case while the four patients who were not surgically operated succumbed to the disease.CONCLUSION Suspected anti-NMDAR encephalitis should be quickly evaluated for anti-NMDAR antibodies since early diagnosis is important.In case of a tumor,its earliest and complete removal is recommended.Finally,early use of corticosteroids and IgG-depleting strategies(intravenous immunoglobulin or plasma exchange)may improve outcome.

Uniportal video-assisted thoracoscopic surgery for complex mediastinal mature teratoma:A case report

BACKGROUND Mediastinal mature teratoma is the most common histological type of primary extragonadal germ cell tumor.In this report,we describe a rare case of giant mature teratoma located primarily in the anterior mediastinum and causing partial atelectasis of the upper and middle lobes of the right lung,as well as extrinsic compression of the right atrium.CASE SUMMARY A 31-year-old male with a giant mediastinal mature teratoma presented with progressive exertional dyspnea and chest pain for 1 mo.Computed tomography of the chest indicated the diagnosis of anterior mediastinal teratoma.The patient underwent right uniportal anterior approach video-assisted thoracoscopic surgery(VATS).En bloc resection of the giant teratoma,wedge resection of the upper and middle lobes of the right lung,resection of the thymus and partial excision of the pericardium were successfully performed.The pathological diagnosis revealed a mature cystic teratoma with foreign-body reaction that was closely related to the right lung,atrium dextrum,superior vena cava and ascending aorta.An atrophic thymic tissue was also discovered at the external teratoma surface.The patient was discharged on postoperative day 7.CONCLUSION This is the first report of the use of uniportal VATS for complete resection of a teratoma in combination with wedge resection of the right upper and middle lung lobes and partial resection of the pericardium.

Ovarian growing teratoma syndrome with multiple metastases in the abdominal cavity and liver:A case report

BACKGROUND Growing teratoma syndrome(GTS)is an unusual presentation of an amazing transformation of teratoma from malignant to benign on pathology during or after systemic or intraperitoneal chemotherapy.The definitive pathogenesis is still not fully understood due to the lack of large-sample studies.CASE SUMMARY A 53-year-old woman underwent radical surgery and postoperative intraperitoneal chemotherapy due to immature teratoma of the right ovary at the age of 28.She remained well during a 25-year follow-up period after surgery.Multiple asymptomatic solid masses were found in the liver on ultrasonography a month ago.Enhanced computed tomography(CT)of the abdomen revealed multiple masses in the abdominal cavity.The largest one was located in the posterior peritoneum next to the sixth segment of the right liver,about 7.9 cm×7.5 cm in size.Three masses were present inside the liver,and one mass was in the right pelvic floor.Multiple lumps in the abdominal cavity were completely removed by surgery.During the operation,multiple space-occupying lesions were seen,ranging in size from 0.5 to 3 cm,and grayish white in color and hard in texture.Ovarian GTS was finally diagnosed based on postoperative pathology.After surgery,she recovered uneventfully.During a 3-year follow-up,the patient remained free of the disease without any recurrence on CT scan.CONCLUSION GTS is a rare phenomenon characterized by conversion of immature teratoma to mature one during or after chemotherapy and presents as growing and metastasizing masses.The pathogenesis of GTS is unclear,and the prognosis is good after surgical resection.

Posterior Mediastinal Mature Teratoma: A Case Report and Literature Review

Mediastinal mature teratoma is the most common form of germ cell tumors, often located in the anterior mediastinum. A posterior mediastinum location has rarely been described. We report a case of a posterior mediastinal mature teratoma in a 37-year-old patient and a literature review, through which we describe the diagnostic and therapeutic difficulties inherent in this particular location of these tumors.

Cystic benign teratoma of the neck in adult

Teratomas are embryonal neoplasms that arise when totipotential germ cells escape the developmental control of primary organizers and give rise to tumors containing tissue derived from all three blastodermic layers. Teratomas have been reported to occur in various sites and organs. Teratoma of the cervical neck are relatively rare in adulthood. It usually extends from the neck to the thoracic cavity causing local mass effect. In most of the cases intrauterine diagnosis is possible by ultrasound. Because of dyspnea due to mass effect, this condition is treated promptly after birth. However cases of teratoma in adulthood with supraclavicular localization have been reported rarely in the literature. The presented case is of a 25-year-old female with a cervical mass. Histological examination revealed a benign mature teratoma. The patient has been disease free for more than nine years after surgical removal of a neck teratoma.

Ganglioneuroblastoma arising within a retroperitoneal mature cystic teratoma

We discuss an extremely rare case of ganglioneuroblastoma arising within a retroperitoneal mature cystic teratoma. Radiological examinations showed a cystic tumor sandwiched between the pancreas and left kidney. Surgery was scheduled because the tumor seemed to have originated from the pancreas. En-block resection of the tumor with distal pancreatectomy, splenectomy, and left adrenalectomy was performed. In terms of macroscopic appearance, the tumor mainly consisted of a unilocular cystic mass, but the presence of a smaller, solid mass was also noted within the tumor. Histopathologic examination confirmed that the cystic mass was consistent with a mature cystic teratoma of the retroperitoneum, and in addition, a ganglioneuroblastoma was evident in the solid component. Histopathologically, the ganglioneuroblastomatous area was intimately associated with dermoid tissue of the mature cystic teratoma, thus this case was diagnosedto be a mature cystic teratoma with malignant transformation. To best of our knowledge, this is the first reported case of ganglioneuroblastoma arising in a mature cystic teratoma.

Malignant transformation of primary mature teratoma of colon:A case report

BACKGROUND Mature teratoma is a common benign ovarian germ cell tumor,accounting for about 20%of ovarian tumors.The malignant transformation of this tumor is less than 2%.The most common type is squamous cell carcinoma,followed by adenocarcinoma.Malignant transformation of colonic mature teratoma is extremely rare.We here report a case of malignant transformation of primary mature teratoma of the colon.The type of malignant transformation was adenocarcinoma.CASE SUMMARY A 63-year-old woman was admitted to our hospital due to persistent pain in her right lower abdomen for 1 mo,and she had no nausea,vomiting,blood in the stools,or other symptoms.Preoperative colonoscopy showed uplift of the sigmoid colon mucosa and submucosa.The biopsy showed squamous epithelium.However,contrast-enhanced computed tomography of abdomen and pelvis showed a localized thickening of the sigmoid wall,suggesting colon cancer.Endoscopic ultrasonography(EUS)revealed that the structure of the intestinal wall at the base of the lesion was destroyed,and the boundary between the lesion and the surroundings was unclear.According to the findings of the EUS,the patient did not undergo endoscopic submucosal dissection,but underwent radical resection of the tumor.Histologically,squamous epithelium was seen on the mucosal surface of the colon wall,cartilage and glands were seen under the epithelium,and adenocarcinoma was seen on the muscular layer and serous surface.The final pathological diagnosis was malignant teratoma of the colon.We have followed up the patient for 2 mo since the operation,and the patient recovered well.CONCLUSION This case suggests the possibility of mature teratoma in the colon and recognition of malignant types,and it should not be considered as an exclusively ovarian tumor.

Cystic teratoma of the parotid gland:A case report

BACKGROUND Teratoma is a common tumor,but rarely occurs in the parotid region.Only nine cases have been reported in the current literature.Although it is generally detected in infancy or childhood,it is commonly asymptomatic.Computed tomography(CT)and magnetic resonance imaging(MRI)have important roles in the diagnosis of teratoma.CASE SUMMARY A 36-year-old man developed a lump located below the left auricular lobule 3 years ago.Physical examination revealed a nearly-circular tumor in the left parotid gland region with a defined border,firm texture,and significant movement.Calcification,fat,keratinized substances,and typical fat-liquid levels was observed on CT and MRI.A diagnosis of cystic teratoma of the parotid gland was established preoperatively and confirmed by postoperative pathology.Following surgery,the patient developed temporary facial paralysis.There was no recurrence of teratoma during the 15-mo follow-up period.CONCLUSION When an asymptomatic mass in the parotid region is identified,parotid gland teratoma should be included in the differential diagnosis.Imaging examinations are helpful in the diagnosis.