Primary Retroperitoneal Mucinous Cystic Neoplasm: Authors’ Experience and Review of the Literature

Primary Retroperitoneal Carcinomas: New Insights into Pathogenesis and Clinical Management in Comparison with Ovarian Carcinomas and Carcinoma of Unknown Primary

Primary retroperitoneal carcinomas are very rare tumors. Their pathogenesis remains unknown but may be associated with that of ovarian carcinomas, considering the similarity in morphology and gender preference. Although metaplasia of coelomic epithelium is the most widely accepted theory, the pathogenesis of retroperitoneal carcinomas may differ by histologic subtype, like ovarian carcinomas. Mucinous carcinoma, which develops in both women and men, may originate in both primordial germ cells and Walthard cell nests that may be derived from the fallopian tube. Serous carcinomas may be associated with endosalpingiosis, the presence of fallopian tube-like epithelium outside the fallopian tube, and a remnant Müllerian tract. Endometrioid and clear cell carcinomas appear to be associated with extraovarian endometriosis. Additionally, both carcinomas in the retroperitoneal lymph nodes may be metastatic diseases from endometrial and/or renal cell cancer that regress spontaneously (carcinoma of unknown primary). Retroperitoneal carcinomas are difficult to diagnose, as they have no characteristic symptoms and signs. Surgery is the cornerstone of treatment, but the necessity of chemotherapy may depend on histological subtype. Further studies are necessary, in particular studies on endosalpingiosis, as endosalpingiosis is a poorly understood condition, although it is associated with the development of both serous and mucinous carcinomas.

Primary Retroperitoneal Mucinous Cystadenocarcinoma: A Case Report

Mucinous neoplasms are commonly seen in the ovaries and pancreas. Their occurrence in the retroperitoneum is uncommon. We present a case of a retroperitoneal mucinous cystadenocarcinoma in a 54-year-old female who presented with right flank pain. Imaging demonstrated an 8.6 × 7.9 cm mass at the anterior surface of the lower pole of the right kidney, suspicious for renal cell carcinoma. Serum tumor markers carbohydrate antigen 19-9 (CA 19-9) and cancer embryonic antigen (CEA) were within normal limits, and cancer antigen 125 (CA 125) was elevated. Surgical resection of the mass was performed. Intraoperatively, the mass was noted to lie in the retroperitoneum, unattached to the kidney. On gross examination, a 10.0 × 7.0 × 7.0 cm unilocular cystic structure with red-brown mucoid material was present. The inner lining was mostly smooth with areas of excrescences, covering less than 5% of the surface area. Microscopic examination showed cystic areas lined by mucinous epithelium with an underlying ovarian-type stroma. Solid areas showed features of a borderline papillary mucinous tumor with invasive carcinoma. A diagnosis of mucinous cystadenocarcinoma was made. Their occurrence in the retroperitoneum is unusual. Although rare, this entity should always be considered in the differential diagnosis of retroperitoneal cystic lesions.

Primary cystic and solid neuroendocrine tumor of the retroperitoneum: A case report

RATIONALE

Primary neuroendocrine tumors (NETs) of the retroperitoneum are extremely rare. The purpose of this case report is to highlight the unusual growth pattern and radiologic features of primary retroperitoneal NETs.

PATIENT CONCERNS

A 46-year-old woman was found to have a retroperitoneal cystic and solid mass during a physical checkup.

DIAGNOSES

The mass was mainly multiseptated in the cystic portion and had a bead-like, lobulated appearance. The solid portion showed restricted diffusion on diffusion-weighted imaging and obvious homogeneous enhancement. The cystic portion showed ring-like and septal enhancement. The patient was diagnosed with a grade 2 (G2) NET of the retroperitoneum after surgery.

INTERVENTIONS

The patient underwent resection of the large retroperitoneal tumor.

OUTCOMES

The patient returned 20 months later with tumor recurrence in the retroperitoneum. She was enrolled in a clinical trial for sulfatinib, and the mass was considerably reduced in size after 4 months. During a nearly 1.5-year follow-up, the mass gradually became slightly enlarged. The expression of somatostatin receptor 2 (SSTR2) was detected, and somatuline was administered as the current treatment.

LESSONS SUBSECTIONS

When a retroperitoneal mass presents as a well-defined cystic or solid hypervascular mass with a fibrous capsule, a primary retroperitoneal NET should be considered in the differential diagnosis.

Laparoscopic Resection and Pre-Operative Imaging of Primary Retroperitoneal Mucinous Neoplasms: A Retrospective Case Series

Purpose

The purpose of this paper is to present the clinicopathological features of primary retroperitoneal mucinous neoplasms (PRMNs), to evaluate the diagnostic role of pre-operative radiological examinations, and to determine the feasibility of total resection using the laparoscopic approach.

Methods

We retrospectively analysed the clinicopathological and radiological features of 10 PRMN cases who underwent surgical resection from January 2000 to December 2019.

Results

Ten PRMN cases were evaluated in this study, including 1 malignant case, 4 borderline cases, and 5 benign cases. The most common primary complaints were pain (60%) and palpable mass (60%). Of the 8 cases with pre-operative CT results, 75% of the borderline or malignant cysts and none of the benign cysts were large in size (size>11.6 cm). Half of the non-benign masses and none of the benign ones were lobulated. Thick wall (≥3 mm) and irregular wall were found in 25% and 50% of the non-benign cases, respectively. Wall enhancement was detected in 75% of the non-benign cases and 25% of the benign cases. Enhanced mural nodules were identified in 50% of the non-benign patients. Septa were found in 25% of the non-benign cases. Complete dissection of the tumour without rupture or post-operative complications was achieved laparoscopically in 90% of the cases. All patients were alive with no recurrence at the last follow-up at an average of 28.1±26.6 months.

Conclusion

Larger size and lobulation of the cyst, presence and contrast enhancement of thick and irregular cyst walls, mural nodules, and internal septa may be imaging features suggestive of malignancy. Complete resection of PRMN through the laparoscopic approach is feasible in experienced institutions.

Primary retroperitoneal tumor during pregnancy: Case report and review of the literature

OBJECTIVE

To report the case of a pregnant patient diagnosed with a primary retroperitoneal tumor and to conduct a review of the literature pertaining to the diagnosis, treatment and maternal-fetal prognosis of this disease condition during pregnancy.

METHODS

A 19-year-old patient who presented with a retroperitoneal tumor identified on ultrasound. The results of the percutaneous biopsy showed a benign tumor. A healthy neonate was delivered by cesarean section. Surgical resection was performed four months later, and histopathology showed a mature cystic teratoma. A search was conduced in the Medline via PubMed, Lilacs, SciELO and ScienceDirect databases using the terms "pregnancy," "neoplasms," and "retroperitoneal neoplasms," including case reports and case series of retroperitoneal tumors during pregnancy. Diagnosis, treatment and maternal-fetal prognosis were identified.

RESULTS

Overall, 1658 titles were identified. Of these, 34 case reports and 1 case series met the inclusion criteria. Of the cases, 62.9 % were benign. Diagnosis was made as an incidental finding in 63 % of cases, and 77 % of the masses were identified on ultrasound. Percutaneous biopsy was used in 8 % of cases, including the case reported here. Surgical treatment was used in 88 % of cases usually after delivery. Maternal mortality occurred in 8.5 % of cases. Fetal prognosis was good in 65 % of the pregnancies.

CONCLUSIONS

Despite being frequently benign, retroperitoneal tumors during gestation have a reserved maternal and fetal prognosis in a substantial number of cases. There is a need to assess the risks and benefits of percutaneous biopsy.

First Report of Retroperitoneal Mucinous Cystadenoma in a Patient with Hirsutism

Primary retroperitoneal mucinous cystadenomas (PRMC) are rare benign neoplasms with only 55 documented cases in the English literature so far. A 19-year-old female exhibited hirsutism and was found to have a cystic mass measuring 5.8 cm × 3.9 cm × 5.8 cm in the left retroperitoneum. During subsequent work up, a high pre-operative value of dehydroepiandrosterone sulfate (DHEA-S) was noted. The patient was referred to surgical oncology and underwent an uneventful laparoscopic cystectomy. Pathology classified the cyst as PRMC. Post-operatively, the patient's DHEA-S levels normalized, though there was no appreciable decrease in the patient's hirsutism in the short-term follow-up. The origin of PRMC is uncertain. Due to their unknown biological potential, surgical resection is usually recommended. To the best of our knowledge, this is the first report documenting a PRMC and elevated levels of androgens in conjunction with hirsutism.

Evaluation of clinical application of multi-slice computerized tomography in primary retroperitoneal tumors

BACKGROUND

To accurately identify primary retroperitoneal tumors by multi-slice spiral CT (MSCT) for better treatment.

MATERIALS AND METHODS

The common types of 380 cases of primary retroperitoneal tumor, lesion sites, and MSCT features were compared with pathological results. Fisher's or chi-square test approaches have been applied in this study.

RESULTS

Multi-slice computerized tomography multi-directional reconstruction has a high accuracy for primary retroperitoneal tumors (95.7%). Seventy-three liposarcoma cases were located in peri-renal space, accounting for 76.8% (13/95) of the tumors in this region. Meanwhile, 65 cases of neurogenic tumors were located in the paravertebral column, accounting for 90.3% (65/72) of the tumors in this region. MSCT examination could effectively distinguish benign from malignant of primary retroperitoneal tumor (sensitivity = 87.2%, specificity = 82.7%, accuracy rate = 84.5%). Malignant tumors showed more irregularity shape than benign tumor (χ²  = 20.468, P < .001). 82.7% (191/231) of the malignant tumors showed adhesion or even invasion of surrounding tissues and organs (χ²  = 23.262, P < .001). Fat density of the lipoma is uniform, and lesion is not enhanced. Liposarcoma can be seen in varying proportions of fat and soft tissue density.

CONCLUSION

The accuracy of MSCT scan for retroperitoneal tumors is high. Meanwhile, the coincidence rate of qualitative diagnosis before operation and/or before biopsy is also high.

A rare case of a primary retroperitoneal mucinous cystic tumour with borderline malignancy and literature review

Primary retroperitoneal mucinous cystic neoplasms (PRMCN) with borderline malignancy are exceptionally rare tumours with lack of pathognomonic clinical and imaging-specific features. Here, we report a case of PRMCN with borderline malignancy in a 62-year-old woman who presented with abdominal pain. Imaging studies revealed a well-defined cystic mass on the right flank in close relation with the cecum and caecal appendix, without other findings suggestive of malignancy. A possible diagnosis of an ovarian epithelial tumour was ruled out intraoperatively. After surgical excision, microscopic examination allowed the final diagnosis. As there is no evidence of disease during follow-up, complete tumour resection without cystic rupture appears to be the best therapeutic option. Thus, although rare, this tumour should be considered when imaging findings suggest an ovarian mucinous neoplasm in women with normal ovaries. An international registry for rare tumours and longer follow-ups may contribute for more consistent approach for managing these patients.

Laparoscopic excision of a retroperitoneal mucinous cystic neoplasm: A case report

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Primary retroperitoneal mucinous cystic neoplasms are rare.

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Due to potential seeding intra-operatively, laparoscopic removal was avoided.

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Our case showed efficient and safe use of a laparoscopic approach.

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Surgeons must plan for every cyst to be malignant when planning for removal.

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With a laparoscopic approach, care is required when aspirating the cyst in vivo.

Introduction

A 22-year-old female presented with a large abdominal mass that was revealed to be a primary retroperitoneal mucinous cystadenoma.

Presentation of Case

A 22-year-old female presented with a two day history of bloating, mid-epigastric pain, and nausea without vomiting. A CT scan of her abdomen/pelvis showed a large left retroperitoneal mass, possibly a mesenteric cyst. The patient underwent laparoscopic surgery for mass excision. Once the cystic mass was completely dissected laparoscopically, it was placed in a large endobag. The fluid was then aspirated while in the bag to decompress and then completely taken out through a port site. She was discharged the following day. Final pathology revealed a benign mucinous cystadenoma/cystadenofibroma of mesenteric origin.

Discussion

Primary retroperitoneal mucinous cysts are rare occurrences and benign mucinous cystadenomas are the rarest subtype. We use an innovative laparoscopic technique with complete excision of the cyst without spillage of content, thus preventing possible seeding in case of malignancy.

Conclusion

There is some previous caution in using a laparoscopic approach for cystic masses due to potential seeding intra-operatively, in case of fluid spillage of a possible malignant neoplasm. We show through our case that it is possible to efficiently and safely use such an approach.

Mucinous tumor arising in a giant sacrococcygeal teratoma: A rare case report

RATIONALE

Teratomas, which most frequently affect adult females, are the most common type of germ cell tumor, it always comprises derivatives of at least 2 germ layers. The most common site of primary teratomas is the ovary. Sacrococcygeal teratomas (SCTs), which are exceedingly rare in adults, are generally found in newborns or children.

PATIENT CONCERNS

A 39-year-old woman presented to our clinic with a 1-year history of gradually aggravated difficulty in micturition and defecation, and a tumor in her right buttock present since birth. Appropriate preoperative examinations showed a large (15.6 cm × 12.2 cm × 30.0 cm) multicystic SCT.

DIAGNOSES

Histologic examination confirmed a mucinous tumor arising in a giant SCT.

INTERVENTIONS

Abdominoperineal rectal resection was performed.

OUTCOMES

The patient recovered well and was discharged on day 33 of admission.

LESSONS

We report the first case of a mucinous tumor arising in an SCT, in which the teratoma presented mature tissue elements derived only from the endodermal germ layer (keratinous debris).