腹膜假粘液瘤的CT表现与病理基础

目的:探讨腹膜假粘液瘤的CT表现及其病理基础。方法:回顾性分析6例经手术病理证实的腹膜假粘液瘤的CT表现,并与手术病理对照分析。结果:6例患者均为腹腔内弥漫性病变,CT表现为粘液样腹水伴有分隔,囊性包块,肝脾表面扇形压迹,肠管受压移位,腹膜外囊性包块。显微镜下可见大粘液池伴血管充血和慢性炎性细胞浸润,粘液中有腺上皮细胞。结论:CT能反映腹膜假粘液瘤的病理学特征。     

Imaging of mucocoele of the appendix with emphasis on the CT findings: a report of 10 cases

AIM: Mucocoele of the appendix denotes an obstructive dilatation of the appendiceal lumen due to abnormal accumulation of mucus. It is sometimes associated with pseudomyxoma peritonei, which predicts a malignant origin. We present the CT findings and additional imaging studies of 10 patients with neoplastic appendiceal mucocoele and discuss the clinical implications. MATERIALS AND METHODS: Abdominal CT findings from 10 patients with appendiceal mucocoele were reviewed. Barium enema, US and MRI were additionally performed in three patients. There were five men and five women aged 45-80 years. Special attention was directed to the shape and nature of the mass, its relation to the caecum and the presence of ascites or peritoneal implants, as well as possible additional ovarian tumours in female patients. RESULTS: The mucocoele was an incidental finding in five patients. They were either spherical or elongated cystic lesions, attached to the wall of the caecum, six of them with mural calcification. Ascites were present in six patients and hypodense large peritoneal implants representing pseudomyxoma peritonei in four. Pathologically the series included five cases of cystadenoma (in one, a malignant pseudomyxoma peritonei subsequently developed), four cases of cystadenocarcinoma and one villous adenoma (this patient later developed pseudomyxoma peritonei). Pseudomyxoma peritonei was found in five cases. Three women had associated ovarian cystic tumour. CONCLUSION: The appearance of an appendiceal mucocoele is quite characteristic and can be diagnosed on CT. CT can also depict additional findings suggesting pseudomyxoma peritonei. In women with an appendiceal mucocoele the ovaries should be examined closely for cystic tumour and vice versa.     

Peritoneal pseudomyxoma. Diagnostic role of CT and ultrasonics

Pseudomyxoma peritonei is an uncommon disorder, usually the sequelae of mucocele or mucinous adenocarcinoma of the appendix or mucinous cistoadenocarcinoma of the ovary. Two cases of pseudomyxoma peritonei were examined by ultrasound and one case by CT. US revealed, in a case, multiple echogenic small masses scattering on the peritoneal surface or floating in ascites. CT showed, in the second case, a huge mass consisting of a low attenuation material with internal septation. Also a perforation of intestinal loops in the mass was demonstrated. CT and US appearance of pseudomyxoma peritonei in our experience and in previously reported cases are discussed.     

腹膜假性黏液瘤的CT诊断

目的:认识和提高腹膜假性黏液瘤的CT表现及诊断.方法:回顾性分析16例经病理或细胞学检查证实的腹膜假性黏液瘤的CT和临床表现.结果:腹膜假性黏液瘤是以黏液性腹水为特征,临床主要表现为腹胀、腹块等.依据CT表现不同可分为弥漫性和局限性两种类型,主要CT表现包括腹水内密度不均匀8例,肝脾表面黏液样结节10例,多发分隔的囊性病变5例和网膜增厚或"网膜饼"征6例.结论:典型的CT表现可以诊断腹膜假性黏液瘤,CT检查可为临床治疗的选择和改善预后提供有价值的信息.     

Imaging findings of urachal mucinous cystadenocarcinoma associated with pseudomyxoma peritonei

Pseudomyxoma peritonei is an uncommon neoplastic condition in which gelatinous fluid-like materials are observed in the peritoneal cavity caused by the dissemination of mucinous adenocarcinoma. Although ruptured appendiceal mucocele is the most common cause, tumors arising from other organs may also cause pseudomyxoma peritonei. We report the imaging findings of an extremely rare case of urachal mucinous adenocarcinoma associated with pseudomyxoma peritonei on computed tomography and magnetic resonance imaging with histopathologic correlation.     

腹膜假性黏液瘤的CT征象及其与免疫组化的关系

目的:通过分析腹膜假性黏液瘤(pseudomyxoma peritonei,PMP)的CT资料,提高对本病CT征象的认识。方法:回顾性分析52例临床确诊的PMP患者的临床和影像资料,总结CT影像特点及与细胞角蛋白(cytokeratins,CK)和上皮膜抗原(epithelial membrane antigen,EMA)的关系。结果:52例患者均表现为全腹腔及盆腔积液,37例可见明显多发腔隔形成,43例可见网膜饼形成,52例见肝脏侵犯,40例见脾脏侵犯,30例可见明显扇贝征,3例出现腹壁侵犯,14例出现钙化灶。CK阳性组28例,12例见扇贝征;CK阴性组15例,12例见扇贝征。EMA阳性组13例,9例见扇贝征;EMA阴性组24例,8例见扇贝征。CK、EMA的阳性组与阴性组在扇贝征分布方面差异具有统计学意义;而在其他CT征象(游离积液、腔隔、网膜饼征)上,差异均无统计学意义。结论:PMP的CT征象具有一定的特征性,扇贝征与CK、EMA可能有一定的相关性。     

腹膜假性黏液瘤CT诊断(附21例报告)

目的:探讨腹膜假性黏液瘤的CT表现,提高对本病的认识.方法:搜集经手术、病理证实的腹膜假性黏液瘤21例,回顾性分析其CT表现.结果:21例中原发瘤恶性8例,其中卵巢黏液囊腺癌3例,阑尾黏液囊腺癌4例,结肠黏液腺癌1例;良性13例,其中阑尾黏液囊腺瘤4例,阑尾黏液囊肿2例,卵巢黏液囊腺瘤6例,胰腺黏液囊腺瘤1例.CT平扫见肝脾等实质脏器边缘扇贝样或结节状压迹,腹腔不规则囊实性肿块,CT值19.9～25.8 HU;脏器周围、网膜间隙、腹腔、盆腔见大量黏液性腹水,CT值10～15 HU;腹膜增厚,厚度1.0～2.0 cm;增强扫描显示囊实性病变仅见囊壁、网膜、腹膜轻度强化,囊内病灶无明显强化.结论:腹膜假性黏液瘤CT表现具有一定的特征,是诊断腹膜假性黏液瘤的重要方法.     

Calcification of pseudomyxoma peritonei following intraperitoneal chemotherapy: CT demonstration

Pseudomyxoma peritonei is essentially mucinous ascites, resulting from the intraperitoneal rupture of a malignant mucinous lesion with seeding of peritoneal surfaces. We report a case of pseudomyxoma peritonei from a perforated mucinous adenocarcinoma of the appendix in which radiographically demonstrable punctate calcifications developed during the course of intraperitoneal chemotherapy.     

Radiologic findings of urachal mucinous cystadenocarcinoma causing pseudomyxoma peritonei

Urachal mucinous cystadenocarcinoma causing pseudomyxoma peritonei is very rare. We report a case of a 59-year-old man with urachal mucinous adenocarcinoma associated with pseudomyxoma peritonei, and our radiologic findings. Ultrasonography revealed a well delineated, large cystic tumor adjacent to the anterior wall of the abdomen. Computed tomography and magnetic resonance imaging revealed a tumor of which the left posterior wall was defective. A large amount of ascites was present in the peritoneal cavity. The ascites caused displacement of the intestinal structures toward the dorsal region. The tumor wall and septa in the ascites were well enhanced on contrast-enhanced images. Radiologically, pseudomyxoma peritonei due to rupture of urachal cystic tumor was considered. The pathologic diagnosis was mucinous adenocarcinoma and pseudomyxoma peritonei.     

腹膜假性粘液瘤的临床病理与影像表现分析

目的:探讨腹膜假性粘液瘤的临床影像学表现及病理组织学特征,提高对本病的鉴别诊断水平。方法:选取13例经手术及病理证实的腹膜假性粘液瘤,全部病例均行腹部CT检查,分析其两种临床病理分型(良性DPAM和恶性PMCA)的影像学表现。结果:两型腹膜假性粘液瘤有部分共同的CT表现,比如凝胶状腹水、肝脾边缘扇贝形压迹、肠系膜的浸润性改变、实质器官内浸润性病灶,以及腹膜粘液团在两型均可见到,不同的征象在于大量粘液蛋白性腹水和粘液团块中的钙化更多见于DPAM,网膜饼、淋巴结病变、网膜种植性团块以及原发病灶的显示更多见于PMCA。DPAM常常没有网膜饼形成,但常可见典型的肝脏边缘压迹。结论:两型腹膜假性粘液瘤的影像学表现各具有一定的特征性,充分认识其CT征象的不同有利于放射诊断医师作出正确诊断。     

多层螺旋CT对腹膜假性黏液瘤的诊断价值

目的 探讨腹膜假性黏液瘤的MSCT表现.方法 搜集经手术、病理证实的腹膜假性黏液瘤11例,回顾性分析其CT表现.结果 腹膜假性黏液瘤的MSCT平扫见腹腔不规则囊实性肿块,CT值18.5～27.6 HU;肝脾等实质脏器边缘扇贝样或结节状压迹,脏器周围、网膜间隙、腹腔、盆腔见大量黏液性腹水;腹膜、大小网膜弥漫性不规则增厚;增强扫描显示囊实性病变仅见囊壁、网膜、腹膜轻度强化,囊内病灶无明显强化.结论 MSCT检查对该病的诊断及鉴别诊断具有重要的价值.     

Chronic colonic perforation in pseudomyxoma peritonei

Pseudomyxoma peritonei (PP) produces abundant mucoid material from the rupture of low grade ovarian or appendiceal mucinous tumours. The unique pattern of cancer dissemination and intraperitoneal mucous re-distribution makes it a distinct clinical condition. It has diverse presentations, mainly as a result of narrowing of the gastrointestinal tract and entrapment of other viscera by gelatinous mucoid material. Imaging is helpful, but not diagnostic of this condition. We report a patient with pseudomyxoma perotonei who had perforation at the recto-sigmoid junction into a large mucinous cyst adjacent to the sigmoid colon. The patient improved clinically with conservative management, with persisting communication and no adverse symptoms reported at 4 months follow-up.     

Appendiceal mucocele with pseudomyxoma peritonei mimicking ovarian tumor with peritoneal carcinomatosis

Appendiceal mucocele with unprompted pseudomyxoma peritonei is a rare malignant tumor, which is difficult to diagnose before surgery. We present a case of a 62-year-old woman, and subsequently discuss the clinical and imaging presentation of mucoceles. Findings on CT scan suggested 2 diagnoses: appendiceal mucocele with pseudomyxoma peritonei and malignant ovarian tumor with peritoneal carcinosis. MRI suggested the former diagnosis, showing a large tubular mass at the base of appendix with discontinuous wall, and no ovarian abnormality, which was confirmed by mini laparotomy and histological study of peritoneal thickened tissue. Treatment consisted of neoadjuvant chemotherapy, with a good response. This case shows the role of imaging in the preoperative diagnosis of appendicular mucoceles; CT scan and MRI, which are useful tools in identifying undetermined lesions of the appendix.     

腹膜腔囊性病变的CT表现

目的：探讨腹膜腔囊性病变的CT诊断及应用价值。方法：对照分析57例腹膜腔囊性病变的CT表现和手术、病理结果。结果：21例腹膜腔囊肿或囊腺瘤、囊腺癌CT均表现为边界清晰的囊性或囊实性包块,7例肠系膜囊肿发现囊肿与肠系膜根部相连。5例腹膜腔假性黏液瘤则在肝脏前、后间隙和结肠下间隙见多个有分隔状囊性肿块。3例腹膜腔囊性间皮瘤局限于下腹腔,壁稍厚,有强化。4例腹膜腔淋巴管瘤位于胃脾肾间隙和胃肝间隙,5例腹膜腔血肿均有外伤史,表现为上腹部器管间隙内边缘清晰的囊性包块。12例腹膜腔脓肿均有腹部手术和术后发热史。结论：CT能清晰地显示腹膜腔囊性病变的部位、形态和范围,对临床诊断和治疗有重要价值。     

Mucocele of the appendix. Retrospective study of 10 cases

PURPOSE: The purpose of our work was to assess the value of abdominal sonography (US) and computed tomography (CT) in the preoperative diagnosis of appendiceal mucocele. MATERIAL: and methods. We retrospectively reviewed 10 cases of mucocele of the appendix, 7 cases without pseudomyxoma peritonei, and 3 cases with pseudomyxoma peritonei. All cases were investigated radiologically by plain film and US, barium enema was performed in 3 cases and CT in 5 cases. RESULTS: Mucoceles of the appendix are rare and their clinical presentation is not specific. US confirms the appendicular involvement, but often poses the differential diagnosis with acute inflammation, abscess or localized appendicular peritonitis. CT appears as a mandatory examination since it allows accurate preoperative diagnosis period. In this series, the diagnosis was made preoperatively in the 5 cases where CT had been performed. CONCLUSION: US is useful to confirm the abnormal pattern of the appendix but does not allow accurate diagnosis of mucocele. CT is more specific and accurate for diagnosis of mucocele of the appendix.     

Uptake of 99mTc-MDP by pseudomyxoma peritonei: a case report

A patient with pseudomyxoma peritonei secondary to a mucin-secreting adenocarcinoma demonstrated striking, diffuse uptake of 99mTc-MDP throughout the abdomen. The radiopharmaceutical distribution accurately delineated the region of tumor involvement within the peritoneal cavity.     

Primary neoplasms of the appendix: radiologic spectrum of disease with pathologic correlation.

Although uncommon, primary appendiceal neoplasms often result in clinical symptoms that may lead to abdominal imaging. Acute appendicitis from luminal obstruction is the most common manifestation for most tumor types. Other manifestations include intussusception, a palpable mass, gastrointestinal bleeding, increasing abdominal girth (from pseudomyxoma peritonei), and secondary genitourinary complications. Asymptomatic appendiceal neoplasms may be discovered incidentally. Mucoceles from either benign or malignant mucinous neoplasms represent the majority of appendiceal tumors detected at imaging but are the least likely to manifest as appendicitis. Pseudomyxoma peritonei is a common manifestation of mucinous adenocarcinoma. Colonic-type (nonmucinous) adenocarcinoma of the appendix is much less common than mucinous tumors and typically manifests as a focal mass without mucocele formation. Carcinoid tumor is the most common appendiceal neoplasm but is less often detected radiologically because it is typically small and relatively asymptomatic. Goblet cell carcinoid tumor and non-Hodgkin lymphoma of the appendix are rare and usually infiltrate the entire appendix. Cross-sectional imaging, particularly computed tomography (CT), is effective in the evaluation of these neoplasms. CT appears to be the modality of choice whenever an appendiceal mass is suspected. CT will help rule out or confirm an appendiceal tumor and may suggest a more specific diagnosis.     

Whole abdominopelvic radiotherapy in the palliative treatment of pseudomyxoma peritonei

Background

Pseudomyxoma peritonei (PMP) is a rare clinical syndrome characterized by mucinous peritoneal disease arising from disseminated peritoneal adenomucinosis. Primary treatment involves a combination of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). There is no consensus on the proper treatment of recurrent PMP. In selected patients, repeated cytoreductive surgery with or without HIPEC might improve outcome. However, every repeated debulking procedure becomes less effective with increased morbidity.

Case report

We present a case of a patient with intestinal obstruction caused by recurrent pseudomyxoma peritonei. We treated the patient with whole abdominopelvic radiotherapy (WAPRT) using intensity-modulated arc therapy (IMAT) to a total dose of 33 Gy, delivered in 22 daily fractions. The treatment was well tolerated and resulted in resolution of the obstruction for a period of 24 months.

Conclusion

To the best of our knowledge, we present the first case report showing the possibility of resolving intestinal obstruction with WAPRT in a patient with recurrent PMP. It is our opinion that WAPRT delivered by IMAT, in analogy with ovarian cancer, should be considered as a palliative treatment option in managing patients with recurrent PMP especially in case of obstruction.     

Hallazgos en imagen en los tumores mucinosos de abdomen y pelvis

This article aims to describe the imaging findings for mucinous tumors of the abdomen and pelvis, which have a similar appearance on imaging tests regardless of the organ in which they develop. Due to the high water content of mucus, the appearance of these tumors is generally similar to that of water on ultrasonography, computed tomography, and magnetic resonance imaging. Another common feature of mucin-producing tumors is that calcifications are often present. The rupture of these lesions and accumulation of mucinous material in the peritoneal cavity gives rise to pseudomyxoma peritonei. It is important to identify mucinous tumors because they have a different prognosis and clinical course than non-mucinous tumors and require different management. Depending on their anatomic location and their imaging characteristics, the treatment approach varies from follow-up to radical surgery together with chemotherapy or radiotherapy or both.