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Yolk sac tumor (YST) is a rare malignant tumor originating from germ cells. YST normally originates from the gonads, rarely occurring in extragonadal sites. We report a 35-year-old man with YST arising in the omentum, which is the first reported case of a primary YST of the omentum in an adult male. The patient presented to the community hospital w...
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Context 1
... 35-year-old man presented to the community hospital with progressive abdominal distension. The patient had been well until 1 month before, when abdominal distension and anorexia developed. A CT scan showed thickening of the omentum with ascites ( fig. 1). Upper and lower endoscopies revealed no abnormal lesions in the digestive tract. The patient underwent open biopsy of the omental mass. Histological evaluation of the specimen revealed tumor cells with vacuolated cytoplasm forming a sheeted, honeycomb-like structure. IHC staining of the tumor showed the following profile: AE1+/AE3+, ...Citations
... Postoperative histopathology and immunohistochemistry emerge as essential gold standards, playing a pivotal role in diagnosing mesenteric yolk sac tumors and distinguishing them from mesenteric cysts. [12] 16, F Mesentery 4 YST NED Park et al. [6] 45, F Omentum NA YST NED Xinghui et al. [13] 3, M Omentum NA YST NR Geminiani et al. [7] 46, F Omentum NA YST NED Kim et al. [14] 37, F Omentum NA YST NED Dulger et al. [15] 19, M Omentum NA YST Died of cardiac arrest Harano et al. [16] 35, M Omentum NA YST NED Present case 22, M Mesentery -YST NED ...
Mesenteric cysts, typically benign and asymptomatic, are incidental findings during abdominal investigations for nonspecific
symptoms. Their origin is commonly in the mesentery of the small bowel, mesocolon, or retroperitoneum. This paper reports
a rare case of a 22-year-old male with a mesenteric cyst presenting as a right lower abdominal mass. Ultrasonography revealed
a heterogenous collection, leading to surgical excision. Histopathology unexpectedly revealed an extragonadal yolk sac tumor
(YST) originating in the mesentery, a rarity often misdiagnosed as a cyst. YST, primarily found in gonads, is infrequently
reported extragonadally. This study contributes to the limited literature on primary peritoneal YST, discussing clinicopathological
parameters and presenting a detailed case. The pathogenesis of extragonadal germ cell tumors, including YST,
remains debated, with migration and stagnation of germ cells during embryonic development proposed as a prevalent theory.
Histopathological examination of extragonadal YST mirrors gonadal YST, featuring various patterns. Immunohistochemistry,
crucial for diagnosis, reveals positive expression for SALL-4, glypican-3, PLAP, AFP, and panCK. SALL-4 emerges as the
most sensitive marker for extragonadal YST. This case underscores the importance of accurate postoperative histopathology
and immunohistochemistry in distinguishing mesenteric YST from cysts, as misdiagnosis can impact prognosis. The rarity
of extragonadal YST emphasizes the need for comprehensive understanding and recognition in clinical practice. The study
contributes valuable insights into diagnosis and management, shedding light on a challenging aspect of surgical pathology.
... Additionally, they may express germ cell (SALL4) and yolk sac (Glypican-3, GATA3, AFP) immunomarkers and/or present with a concurrent elevation of serum AFP levels [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Tumors with similar characteristics (yolk sac-like histology, immunohistochemical loss of SMARCB1/INI1 and SMAR-CA4/BRG1, and elevated serum AFP levels) have also been reported in other sites, especially in the female genital tract [17][18][19][20][21]. Based on these findings, we hypothesized that testicular YSTpt may demonstrate similar alterations. ...
... This tumor may exhibit a yolk sac-like histology with the expression of germ cell and yolk sac immunomarkers (SALL4, Glypican-3, GATA3, and AFP) and concurrent elevation of serum AFP levels [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Tumors with similar molecular, morphologic, immunophenotypic, and clinical features have been also reported in other sites, especially in the female genital tract [17][18][19][20][21]. In the classification of germ cell tumors recently proposed by Oosterhuis JW et al., these tumors have been classified as "type-VI germ cell tumors", as tumors derived through the reprogramming of somatic cells to a pluripotential state [32]. ...
The recently described SWI/SNF complex-deficient sinonasal carcinoma (SMARCB1 & SMARCA4) may exhibit a yolk sac-like morphology. Tumors with similar features (yolk sac-like histology combined with the immunohistochemical loss of SMARCB1/INI1 and/or SMARCA4/BRG1) have also been described in other sites, such as the female genital tract. In this study, we immunohistochemically assessed SMARCB1/INI1 and SMARCA4/BRG1 expression to evaluate if these proteins could be involved in the pathogenesis of testicular yolk sac tumors of postpubertal type (YSTpt). Specifically, we analyzed a retrospective case series comprising pure YSTpt and mixed germ cell tumors of the testis (GCTT) with YSTpt components. In the present study, no testicular YSTpt showed loss of SMARCB1/INI1 (0/24, 0%) or SMARCA4/BRG1 (0/24, 0%). However, testicular choriocarcinoma (CHC) and isolated syncytiotrophoblast cells (iSTCs) demonstrated abnormal staining patterns for SMARCA4/BRG1 [CHC: 4/4 (100%); iSTCs: 12/12 (100%), respectively], including focal or diffuse loss of expression in a subset of cases. The results of our study suggest that functional loss of SMARCA4/BRG1 represents a recurrent event that may be relevant for the pathogenesis of a subset of testicular CHC.
... Primary extragonadal YST is a rare malignancy that seldom occurs in the peritoneum. Thirteen cases in primary peritoneal YST have been reported in literatures, including 10 cases in omentum (6,7,11,12,(18)(19)(20)(21)(22)(23)) and 3 cases in mesentery (24, 25). To our knowledge, our case is the first primary relapsed and refractory peritoneal YST reported in the literature. ...
Background
Extragonadal yolk sac tumor (YST) of peritoneum is a rare malignancy.
Case Description
A 37-year-old Chinese woman was admitted to hospital with a 3-month abdominal pain 4 years ago. Alpha-fetoprotein was 228,499.0 ng/mL. Computed tomography scan revealed a massive mass in the left lower abdomen. Exploratory laparotomy exposed a huge mesenteric mass. Then, mesenteric tumor resection, partial sigmoidectomy, and single-lumen fistula of sigmoid colon were performed. Postoperative pathologic diagnosis reported a stage IV mesenteric YST. After surgery, the patient received 6 courses of BEP (bleomycin, etoposide, and cisplatin) chemotherapy. Seven months later, the patient underwent stoma reversion of sigmoid colon and received another 2 courses of BEP chemotherapy. Three months after the last chemotherapy, liver metastases were diagnosed. She subsequently underwent 3 surgeries, radiotherapy for liver metastases, and multiple tiers of palliative chemotherapies, including TP (docetaxel and carboplatin), VIP (ifosfamide, cisplatin, and etoposide), TIP (paclitaxel, ifosfamide, and cisplatin), and so on. After the third surgery (left hepatic lesion resection and right iliac lymph node resection), she received 4 cyclic chemotherapies of BEP´ (boanmycin, etoposide, and cisplatin) without pulmonary toxic side effects.
Conclusion
Postoperative histopathology and immunohistochemistry are gold standards for the diagnosis of peritoneal YST. The standard first-line treatment is surgery plus BEP chemotherapy. Second-line therapy regimens and above, including VIP and TIP, improve the prognosis of recurrent germ cell tumors. This relapsed and refractory patient with peritoneal YST benefits from the secondary BEP´ chemotherapy.
... With the lack of obvious origin elsewhere, a yolk sac tumor predominantly affecting omentum and spreading onto surrounding structures is highly suspected to truly originate from the omentum (Figure 4). In total, there are eight cases of primary omental yolk sac tumors reported in the literature to date, summarized in Table 1 [25][26][27][28][29][30][31][32]. Generally, the omentum is an extremely rare location of this tumor. ...
This is a case report of a rare finding of an extragonadal yolk sac tumor in a 37-year-old patient who presented with shortness of breath and abdominal bloating. During imaging and staging surgery, the findings were strongly suggestive of an extragonadal advanced tumor presenting with peritoneal dissemination, predominantly affecting omentum, with no clear primary origin. Histology revealed an extragonadal yolk sac tumor in a pure form outside the ovaries. Lacking an obvious origin elsewhere, the tumor was highly suspected to have truly originated from the omentum. The patient underwent surgery and four cycles of chemotherapy consisting of cisplatin, etoposide, and bleomycin. One-year outpatient follow-up thereafter showed no relapse. We herein discuss a possible site of the tumor origin and its development, as well as diagnostic challenges and disease prognosis.
... Many studies have reported that YST occurs in the vagina, seminal vesicle, pancreas, omentum and stomach, as well as in the intracranial and sacrococcygeal regions (2,3,(16)(17)(18)(19)(20)(21)(22)(23). GCTs originating in the intracranial region almost always occur in the suprasellar regions or pineal gland, but tumors in the cerebellar hemisphere are extremely rare (2). ...
... At present, there are two theories to explain the occurrence of primary extragonadal GCTs. One is the abnormal differentiation of somatic cells, the other is the malignant transformation of germ cell residues in the process of migration (16,19). The latter may be more suitable to explain the YST location in our case. ...
Yolk sac tumor (YST) is one of rare malignant germ cell tumors (GCTs). Primary intracranial YST, also endodermal sinus tumor (EST), is a quite rare type of brain tumor. Here, we report a case of YST, review the relevant literature, and propose a treatment strategy for this rare tumor. A 6-year-old boy initially manifested symptoms of dizziness and vomiting. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large irregular oval tumor in the cerebellar hemisphere. We subtotally removed the tumor by microsurgery through the left suboccipital approach. Immunohistochemical staining showed that alpha fetoprotein (AFP) was positive and the Ki-67 proliferation index was high (60%), suggesting a germ cell tumor. After 3 months of follow-up, neither recurrence of tumor nor complications were found in the patient. The diagnosis of YST should be confirmed on the basis of clinical manifestations, neuroimaging and pathological findings. Gross total resection (GTR) is an ideal treatment for YST. However, due to the location of the tumor, GTR is usually difficult, and the rate of postoperative complications is high. This reported case shows that subtotal resection can be a good treatment strategy for YST.
... [1,3,4] Most germ cell tumors (GCT) occur in the gonads, but ~20% of cases arise in other locations: mediastinum, sacrococcygeal region, retroperitoneum, cervix, vulva, pelvis, lung, head/ neck, stomach, omentum, bladder, endometrium, kidney, prostate and liver. [5][6][7][8][9][10] Several hypotheses have been offered to explain the histogenesis of EGCTs and include (1) arrested migration or misplacement of germ cells during development, (2) reverse migration of germ cells, (3) aberrant differentiation of somatic cells, (4) derivation from pluripotent stem cells within a somatic tumor, (5) origination from residual fetal tissue following incomplete abortion (uterine-based lesions), and (6) metastases from an occult gonadal primary malignancy. [11] Given the midline tumor location, the sex of the patient and the absence of either a testicular or other occult primary, we speculate that theories 1-3 are applicable; nevertheless, a definitive characterization is not possible. ...
... [23] Treatment of YST includes combination chemotherapy and surgical intervention; radiation is ineffective. [5,6] Following clinical, radiological and pathological evaluations, parameters are used to determine the risk of disease and the management of previously untreated patients to determine the correct chemotherapeutic regimen. [5] Patients are placed into low, intermediate or high risk categories based on anatomical location of the primary tumor, levels of biomarkers prior to beginning treatment, serum LDH values and overall tumor burden. ...
... [5,6] Following clinical, radiological and pathological evaluations, parameters are used to determine the risk of disease and the management of previously untreated patients to determine the correct chemotherapeutic regimen. [5] Patients are placed into low, intermediate or high risk categories based on anatomical location of the primary tumor, levels of biomarkers prior to beginning treatment, serum LDH values and overall tumor burden. [5] The lesion in this case displayed several defects consistent with tumor rupture and the patient was assessed as intermediate risk with stage III disease. ...
Germ cell tumors in extragonadal sites are uncommon; those arising in the urachus are exceedingly rare and limited to a few anecdotal reports. Herein we document an occurrence of yolk sac tumor in a 9-month-old male who presented with abdominal distension. Laboratory investigation revealed elevated lactate dehydrogenase and α-fetoprotein levels; imaging studies were inconclusive as to tumor type or site of origin. The tumor was resected from the base of the umbilicus and histologic examination revealed neoplastic cells arranged in solid nests or microcystic patterns in a fibromyxoid stroma. Schiller-Duval bodies were conspicuous. Immunohistochemical analysis showed lesional cells reactive to α-fetoprotein, SALL4, placental alkaline phosphatase, Glypican-3 and CD117. No teratomatous or other germ cell elements were identified. These findings supported a diagnosis of pure yolk sac tumor arising from the urachus; the clinical, radiological and pathological findings are discussed.DOI:10.276/APALM.1832
... The optimal treatment is the surgical resection of the tumor, followed by adjuvant chemotherapy (including bleomycin, etoposide and cisplatin) (3), however, the results are poor. Approximately 80-90% of YSTs arise in the reproductive organs, but may also occur in the extragonadal regions (1,(4)(5)(6)(7)(8)(9)(10)(11)(12). There have been several previously reported intracranial cases, the majority of which were observed in the pineal region. ...
... Endodermal sinus tumors are rare malignant GCTs that usually originate from the gonads and are rarely observed extragonadally (4). Several case studies have reported the occurrence of this entity in the vagina, seminal vesicle, omentum, pancreas and stomach, as well as in the sacrococcygeal and intracranial regions (1,(5)(6)(7)(8)(9)(10)(11)(12). GCTs originating in the intracranial region almost always occur in the pineal gland or suprasellar regions, therefore, a tumor arising in the cerebellar hemisphere is extremely rare (1). ...
... The histogenesis of extragonadal YST remains controversial. There are currently two theories that may explain the occurrence of primary GCT at extragonadal sites; the first is the aberrant differentiation of somatic cells, while the second is the malignant transformation of remnant of germ cells along the pathway of migration (6,7). The latter may be more feasible for explaining the location of the YST in the present case. ...
Endodermal sinus tumors are rare malignant germ cell tumors that usually originate from the gonads and are rarely observed extragonadally. Pure primary endodermal sinus tumors of the cerebellar hemisphere are extremely rare and patients diagnosed with the disease often have a poor prognosis. The symptoms of YSTs are unspecific and associated with the location of tumors. Intracranial YSTs (such as cerebellar hemispheres) always present with symptoms including headache and poor vision. The present study reports the case of a three-year-old male who presented to The First Affiliated Hospital of Nanchang University (Nanchang, China) with a headache that had persisted for one month, and then worsened for the last 10 days. This was accompanied by vomiting and gait disturbance. An abnormal signal mass was identified in the left cerebellar hemisphere on brain magnetic resonance imaging. The case initially presented as a medulloblastoma and the patient was followed up for six months. The final pathology report revealed an endodermal sinus tumor, also known as a yolk sac tumor. Six months following resection of the left cerebellar tumor, the patient succumbed to recurrence of the disease, due to acute vomiting and severe headache.
Yolk sac tumor (YST), which most frequently arises in the gonads as a type of germ cell tumor, is rare in children but is highly malignant. It has been suggested that alpha-fetoprotein (AFP) can be applied as a feasible tumor marker because its level was elevated in >90% of YST. The treatment generally involves debulking surgery of tumors followed by systemic chemotherapy. Metastasis process of YST in children is different from that in adults and thus the treatment option is required. In this study, we described a rare case of YST in terms of the clinical manifestation, imaging, and histopathology findings, diagnosis and treatment in an 8-year-old girl. Furthermore, it is important to investigate more thoroughly a patient with history of intermittent abdominal pain and fever with previously multiple accesses, because these might be the critical signs for YST that should be alarmed for early treatment. Although YST is rare in children, pediatric physicians should be aware of this and prompt treatment should be addressed.
Extragonadal primary yolk sac tumor of the intestinal tract origin is exceedingly rare. Through a multiple disciplinary team, the diagnosis and treatment of primary intestinal yolk sac tumor were further defined. We report 2 such cases with detailed histologic and immunohistochemical analysis. The two patients were a 7-year-old girl and a 29-year-old woman. Both of them preoperatively had an elevated serum alpha fetoprotein (AFP) level (≥ 1,210 ng/mL). The tumors are located in the intestine and imaging examination indicated the rectum as the primary site. Grossly the mass was grey-white and crisp texture. Microscopic examination featured reticular, microcystic, macrocystic, papillary, solid, and some glandular patterns. Immunohistochemically, tumor cells of both cases were positive for SALL4, AFP, pan-cytokeratin (AE1/AE3), and glypican-3. Simultaneously, a stain for EMA, OCT4, CD30, HCG, vimentin and CK20 were negative in all 2 neoplasms. The features of morphology, immunohistochemistry, laboratory examinations and imaging studies consist of the diagnosis of primary yolk sac tumor of the intestine.
Extragonadal germ cell tumors are uncommon, and although they morphologically resemble their gonadal counterparts, unexpected gonadal presentation increases the potential for erroneous diagnoses. Yolk sac tumor is a malignant germ cell tumor characterized by an extraembryonic yolk sac line of differentiation, and relative to other germ cell tumors, is characterized by varied and diverse histologic patterns. When occurring outside of typical age parameters or in extragonadal locations, the histologic variability of yolk sac tumor and its tendency to mimic somatic tumors pose diagnostic challenges. Because extragonadal yolk sac tumor of the vulva is very rare, with only isolated case reports and small series in the literature, it is often not considered in the differential diagnosis. As both prognosis and management of yolk sac tumor differ significantly from those of somatic tumors, accurate diagnosis is essential. This review discusses histologic features of extragonadal yolk sac tumor, addresses somatic tumors arising in the vulva for which yolk sac tumor may be confused, and provides guidance with respect to the use of immunohistochemistry in the diagnosis of yolk sac tumor.
