Clinicopathological analysis of primary epithelial appendiceal neoplasms

Appendiceal carcinomas are classified into three distinct histopathological disease entities: disseminated peritoneal adenomucinosis (DPAM), peritoneal mucinous carcinomatosis (PMCA), or peritoneal mucinous carcinomatosis with intermediate or discorant features (PMCA I/D). The treatment of appendiceal tumors should be based on accurate histopathological classification, per previously reported case series. The objective of this study was to evaluate the clinicopathologic presentation and outcome of patients with appendiceal tumors treated at our institution over a 15-year period. We identified patients with appendiceal tumors diagnosed or treated at our institution from January 1989 through May 2004. Chart review for age, gender, signs and symptoms at diagnosis, and treatment was performed. Review of the pathologic specimens was performed and tumors were classified as DPAM, PMCA I/D, or PMCA. Forty patients were identified (median age 52.5 years; males 38%). The number of patients with DPAM, PMCA I/D, and PMCA was 15 (38%), 6 (15%), and 18 (46%), respectively. Peritoneal involvement was seen in 11 (73%) of patients with DPAM, 5 (83%) of PMCA I/D, and 11 (61%) of PMCA. The median survival for patients with DPAM, PMCA I/D, and PMCA was 7.7 years (90% CI: 2.9—upper limit not estimable), 1.2 years (90% CI: 0.9–1.6), and 0.7 years (90% CI: 0.4–1.5), respectively. The difference in survival across the three groups was statistically significant. Three distinct histopathological disease entities exist in appendiceal tumors. The prognosis and management of these tumors should be based on the extent of disease and pathologic diagnosis.     

COX-2 expression in pseudomyxoma peritonei

COX-2 expression was studied using an immunohistochemical method in 75 patients with pseudomyxoma peritonei (PMP). Twenty-five patients presented with disseminated peritoneal adenomucinosis (DPAM) and 50 with peritoneal mucinous carcinomatosis (PMCA). COX-2 was expressed in neoplastic mucinous epithelium of 30 cases (40%): 20 in PMCA (40%), 10 in DPAM (40%). Weak COX-2 expression was also noted in four of five patients with appendiceal mucinous neoplasms without peritoneal dissemination. In addition, COX-2 was detected in stromal, endothelial, inflammatory cells and reactive mesothelium. This preliminary information indicates a potential for the use of COX-2 inhibitors in patients with PMP.     

Management and prognosis of low-grade appendiceal mucinous neoplasms: A clinicopathologic analysis of 50 cases

Background

Low-grade appendiceal mucinous neoplasms (LAMN) are poorly understood lesions characterized by their potential to spread to the peritoneal cavity as pseudomyxoma peritonei (PMP). The purpose of this study was to investigate the clinical and pathologic features and management of these tumors.

组织学分型对于CRS联合HIPEC治疗后的阑尾黏液性肿瘤预后评估的临床意义

  目的  阑尾黏液性肿瘤较为罕见,可发生腹膜转移形成腹膜假黏液瘤。目前,临床上多应用肿瘤细胞减灭术（cytoreductive surgery,CRS）和腹腔热灌注化疗（hyperthermic introperitoneal chemotherapy,HIPEC）进行治疗。其组织学类型、腹膜癌指数（peritoneal carcinomatosis index,PCI）评分及细胞减灭程度（completeness of cytoreduction,CC）评分等因素和预后的相关性尚为明确。将规范的组织学分类作为预测因子应用至临床,探讨不同组织学分型、PCI评分和CC评分等因素对伴有腹膜转移的阑尾黏液性肿瘤的预后影响。  方法  回顾行分析2009年3月至2019年1月重庆大学附属肿瘤医院就诊的经CRS联合HIPEC治疗后的阑尾黏液性肿瘤的转归。按照2019年第5版世界卫生组织（WHO）对消化道肿瘤推荐的分类标准和国际腹膜表面肿瘤组的规范化组织学分型,采用Cox比例风险模型,通过单变量和多变量分析明确组织学分型、PCI评分、CC评分对患者无进展生存期(progress free survival, PFS)的影响。  结果  共48名患者接受了CRS+HIPEC的治疗。经单因素Cox回归分析,PCI 评分 、CC评分、原发组织学类型和腹膜组织学类型均对PFS存在影响,差异具有统计学意义（P<0.05）。表现为与PCI评分≤10分相比,20～30的危险比为10.38;CC评分与0分相比,1分和3分的危险比分别为4.26和14.74;原发组织学类型中与低级别黏液性肿瘤相比,印戒细胞癌的危险比为9.81;腹膜组织学类型中,与无细胞黏蛋白相比,高级别腹膜黏液癌的危险比为14.35。经多因素Cox回归分析,仅原发组织学类型对PFS存在影响,差异具有统计学意义（P<0.05）,原发组织学类型中与低级别黏液性肿瘤相比,印戒细胞癌的危险比为110.79。  结论  对于经过CRS+HIPEC治疗阑尾黏液性肿瘤及其引起的腹膜假黏液瘤,规范化地进行原发病灶和腹膜病灶组织学分型对患者预后评估具有重要意义。腹膜病灶组织学恶性程度与原发病灶组织学恶性程度相比呈正相关。原发病灶和腹膜灶恶性度越高,患者预后越差。相对于腹膜病灶组织学分型,原发病灶组织学分型与患者预后更为密切,是更好的预测指标。同时,患者预后与CRS的CC评分和PCI评分有关,PCI评分和CC评分越高,患者预后越差。因此,在CRS+HIPEC治疗中,应对原发病灶和腹膜病灶进行组织学分型,尽可能减瘤彻底,规范化地HIPEC治疗使患者获益。      

Clinically aggressive pseudomyxoma peritonei: a variant of a histologically indolent process

BACKGROUND: Three distinct morphologic types of pseudomyxoma peritonei syndrome have been defined: disseminated peritoneal adenomucinosis (DPAM), peritoneal mucinous carcinoma (PMCA), and a hybrid morphologic type. Prognosis is best in patients with DPAM; unfortunately, some patients with DPAM succumb to a rapidly progressive disease process. METHODS: We identified a subset of 11 patients with a histopathology of DPAM but a clinical course showing an invasive disease process. As a comparison group, from a database of 501 patients with pseudomyxoma peritonei, we selected 22 age- and sex-matched controls with a DPAM histology who are alive with no evidence of disease. Clinical factors were identified for comparison of case and control groups. Expression of mucin antigens, mucin (MUC)1 and MUC2, were evaluated using immunohistochemistry. RESULTS: The study group consisted of 11 patients (five men and six women), with a median survival of 52.2 months (SD 7.46) and a 31% 5-year survival. All 22 matched control cases (10 men and 12 women) are alive and disease-free. Clinical data on the study and control groups including co-morbidity were similar. No significant difference in the expression of MUC1 (P = 0.74, Fisher's exact test) or MUC2 (P = 0.34, Fisher's exact test) was demonstrated between groups. CONCLUSIONS: Further investigation of pseudomyxoma peritonei at a molecular and genetic level may help to formulate a more comprehensive classification.     

Validating the PSOGI classification of peritoneal disease from non-carcinoid epithelial appendiceal neoplasms in the curative and palliative setting: an observational retrospective study

BackgroundFew studies on long-term survival have been published since the new updated pseudomyxoma peritonei (PMP) classification was published in 2016. The aim was to investigate long-term survival according to the Peritoneal Surface Oncology Group International (PSOGI) classification and compare prognostic factors.MethodsFrom Uppsala University Hospital, consecutive patients referred for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) from 2004 to 2017 with peritoneal disease from non-carcinoid mucinous epithelial appendiceal neoplasms were included in the study. The peritoneal disease was divided into four groups: mucin only, low-grade mucinous carcinoma peritonei (MCP-1), high-grade (MCP-2), and high-grade with signet ring cells (MCP-3). Survival curves were rendered, and prognostic factors were compared.ResultsThe study included 223 patients: 36 with mucin only, 112 with MCP-1, 70 with MCP-2, and 5 with MCP-3. Thirty-eight patients had a palliative debulking or open/close procedure. The 5- and 10-year overall survival was 97% and 97% for mucin only, 83% and 70% for MCP-1, 69% and 49% for MCP-2, with no patients still under follow-up after 5 years in the MCP-3 group. In a multivariable analysis, completeness of cytoreduction (CC) score 2–3 and PSOGI class MCP-3 were significantly associated with lower survival. The 5-year overall survival in the palliative setting was 40% vs. 44% (MCP-1 vs. MCP-2, P>0.05) with median survival 51 vs. 53 months, respectively.ConclusionsThe PSOGI classification of PMP provides a solid differentiation of prognostic groups after CRS/HIPEC treatment, but not in the palliative setting.     

The etiology, clinical presentation, and management of pseudomyxoma peritonei

PMP is a rare condition, which, although of "borderline malignancy," is invariably fatal. Difficulties exist with the definition of PMP. It has been broadly applied to include a heterogenous group of pathologic lesions that present clinically with "jelly belly" due to mucinous ascites. The relatively few reports in the literature commonly use different pathologic definitions, and there is no consensus on the point of separation between PMP and carcinomatosis secondary to a mucinous adenocarcinoma. Sugarbaker has suggested "the term pseudomyxoma peritonei syndrome be strictly applied to a pathologically and prognostically homogenous group of cases characterized by histologically benign peritoneal tumors that are frequently associated with an appendiceal mucinous adenoma." This definition excludes all cases with mucinous adenocarcinoma. The optimal treatment is undoubtedly complete tumor excision, by complex surgical peritonectomy procedures, taking on average 10 hours. Surgery is usually combined with intraperitoneal, and now intraoperative heated chemotherapy. These techniques have a high morbidity and mortality. The rarity of the condition, together with the risks associated with definitive treatment, suggests that such treatment ought to be centralized in a few centers, covering a large population. The search continues for safer, less aggressive treatments, but is hampered by a lack of hard evidence and the absence of experimental animal or human models to evaluate emerging strategies.     

Efficacy of a novel mucolytic agent on pseudomyxoma peritonei mucin,with potential for treatment through peritoneal catheters

Compared to current treatment for pseudomyxoma peritonei (PMP), the extraction of solubilised mucin through peritoneal catheter can be minimally invasive. However, mucin has variable appearance that may influence mucolysis. Hence, we investigated the mucolysis of 36 mucin samples with a novel agent. Using visual inspection and hardness index, PMP mucin was classified into three grades. The mucin pathological category was identified from patient record. Subsequently, the dissolution of the samples was tested. For in vitro, 1 g of mucin was treated to the mucolytic agent in 10 ml TRIS buffer at 37 deg. Celsius for 3 hours, with weighing of residual mucin. Control treatment was similar but received TRIS buffer. For in vivo, 2 g of implanted intra-peritoneal mucin in nude rats was treated to mucolytic (2 X 500 ul/24 hr, over 48 hours, plus another treatment before sacrifice at 56 hours, with weighing of residual mucin. Controls were treated but only with TRIS buffer. Six animals were used for each mucin grade (3 mucolytic treated & and 3 controls). Grades of mucin were soft mucin (62%), semi hard (20%) and hard mucin (18%). Diffuse peritoneal adenomucinosis had 50% of soft mucin and peritoneal mucinous carcinoma had 11% (P = 0.0382). In vitro and in vivo absolute disintegration was 100% for soft, 57.38% and 48.67% for semi hard, 50% and 28.67% for hard mucin. Majority of mucin were soft with complete disintegration, the rest showed variable disintegration, suggesting that the mucolytic has potential for treating PMP.     

Recommendations in the management of epithelial appendiceal neoplasms and peritoneal dissemination from mucinous tumours (pseudomyxoma peritonei)

The epithelial appendiceal neoplasms are uncommon and are usually detected as an unexpected surgical finding. The general surgeon should be aware of the diversity of its clinical manifestations and biological behaviors along with the significance of the surgical treatment on the progression of the illness and the prognosis of the patients. The operative findings and, especially, tumor histology, determine the type of surgery. Intestinal histologic subtype behaves and should be treated similarly to the right colon neoplasms; while mucinous tumors, often discordant between histology and its aggressiveness, can be treated with a simple appendectomy or require complex oncological surgeries. Mucinous tumors are often associated with the presence of mucin or tumor implants in the abdominal cavity, being the clinical syndrome known as pseudomyxoma peritonei (PMP). PMP tends to present an indolent but deadly evolution and requires a multimodal approach as a single treatment with curative potential: complete cytoreductive surgery plus hyperthermic Intra-peritoneal chemotherapy (CCRS + HIPEC) now considered the standard of care in this pathology. The general surgeon should be aware of the governing principles of the treatment of appendiceal neoplasms with or without peritoneal dissemination, know the therapeutic frontiers in every situation (avoiding unnecessary or counterproductive surgeries) and sending early these patients to specialised centres in the radical management of malignant diseases of the peritoneum in the conditions and with the necessary information to facilitate a possible radical treatment.     

Appendiceal neoplasms and pseudomyxoma peritonei: A population based study

Background

Pseudomyxoma peritonei (PMP) is a rare disease with an estimated incidence of 1 per million per year, and is thought to originate usually from an appendiceal mucinous epithelial neoplasm. However it is not known exactly how often these neoplasms lead to PMP. The aim of this study is to investigate the incidence of both lesions and their relation.

Methods

The nationwide pathology database of the Netherlands (PALGA) was searched for the incidence of all appendectomies, the incidence of primary epithelial appendiceal lesions and the incidence and pathology history of patients with PMP. All regarded the 10-year period of 1995–2005.

Results

In the 10-year period 167,744 appendectomies were performed in the Netherlands. An appendiceal lesion was found in 1482 appendiceal specimens (0.9%). Nine percent of these patients developed PMP. Coincidentally, an additional epithelial colonic neoplasm was found in 13% of patients with an appendiceal epithelial lesion. A mucinous epithelial neoplasm was identified in 0.3% (73% benign, 27% malignant) of appendiceal specimens and 20% of these patients developed PMP. For mucocele and non-mucinous neoplasm the association with PMP was only 2% and 3%, respectively. From the nationwide database 267 patients (62 men and 205 women) with PMP were identified, which demonstrates an incidence of PMP in the Netherlands approaching 2 per million per year. The primary site was identified in 68% and dominated by the appendix (82%).

Conclusions

Primary epithelial lesions of the appendix are rare. One third of these lesions are mucinous epithelial neoplasms and especially these tumours may progress into PMP. The incidence of PMP seems to be higher than thought before. Furthermore there is a considerable risk of an additional colonic epithelial neoplasm in patients with an epithelial neoplasm at appendectomy.     

Epithelial cells and other cytologic features of pseudomyxoma peritonei in patients with ovarian and/or appendiceal mucinous neoplasms: a study of 12 patients including 5 men

BACKGROUND: Pseudomyxoma peritonei (PP) is a rare condition. Cytologic evaluation of peritoneal fluid often is an initial diagnostic test for possible ovarian and/or appendiceal primary tumors. Previous studies suggest that patients with PP who have epithelial cells (ECs) in their peritoneal fluid usually have a less favorable prognosis than patients with acellular PP. To the authors' knowledge, few reports of PP in the cytologic literature cite the presence of ECs. METHODS: Twelve cases of PP diagnosed by cytologic examination at the University of Texas M. D. Anderson Cancer Center over 15 years were identified. In all cases, primary tumors were confirmed histologically. All available cytologic smears and cell block sections were reviewed for cytomorphology, with particular attention given to the presence of ECs. A correlation between the presence of ECs and patient outcome also was sought (median follow-up, 26 months). RESULTS: Two patients had ovarian neoplasms, six patients (one female and five males) had appendiceal neoplasms, and four patients had synchronous ovarian and appendiceal tumors. Cytologic features included mucin pools (12 of 12 patients), ECs (11 of 12 patients), mesothelial or mesothelial-like cells (10 of 12 patients), histiocytes (11 of 12 patients), and fibroblast-like or spindle cells (6 of 12 patients). ECs were columnar with mucinous features in the majority of cases, and the number of ECs in each case was variable, ranging from 1+ (rare) to 3+ (many). Of the 11 patients with available follow-up data, 6 had recurrent disease, 4 had persistent disease, and 1 patient with acellular PP was alive without clinical evidence of disease after 24 months of follow-up. CONCLUSIONS: Unlike previous PP cytology reports, the current study frequently identified ECs (92%). Because of the potential prognostic implication of ECs in patients with PP, a diligent search for ECs is warranted. Indication of the presence or absence of ECs in the cytology report may be useful when PP is diagnosed.     

Indications and outcomes for repeat cytoreductive surgery and heated intra-peritoneal chemotherapy in peritoneal surface malignancy

IntroductionCytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is offered in specialist centres as a treatment for peritoneal surface tumours. Despite its demonstrated efficacy, intra-abdominal recurrence occurs in 31–57% of patients. The aim of this study is to review the early and long-term outcomes in patients who undergo repeat CRS/HIPEC.Materials and methodsA retrospective review of a prospectively maintained database of patients who had undergone repeat CRS/HIPEC for appendiceal neoplasms and colorectal peritoneal metastases (CRPM) from 2003 to 2019 was performed at a single specialist centre. Data pertaining to both short term outcomes and survival were evaluated.ResultsOf 1259 patients who had undergone CRS/HIPEC, 84(6.7%) underwent repeat surgery: 45(53.6%) had pseudomyxoma peritonei (PMP) secondary to low grade appendiceal mucinous neoplasms (LAMN), 21(25.0%) had appendix carcinoma and 18(21.4%) had CRPM. Demographics, intra-operative findings and short-term outcomes were comparable across tumour types and between procedures. Median (95% CI) interval between procedures was 22.7(18.9–26.6) months and was comparable between tumour types. Median (95%CI) overall survival was not reached for the cohort overall or for those with PMP, but was 61.0(32.6–89.4) months for those with appendix cancer and 76.9(47.4–106.4) months for CRPM (p=<0.001). Survival was favourable in the PMP group (HR [95%CI] 0.044 [0.008–0.262]; p = 0.000) and unfavourable in the CC2-3 at index CRS procedure group (HR [95%CI] 25.612 [2.703–242.703]; p = 0.005).ConclusionOur findings demonstrate that repeat cytoredutive surgery with HIPEC can result in favourable survival, especially for patients with PMP when complete cytoreduction is achieved at index operation. We recommend that detailed patient assessment is performed through an expert multidisciplinary team meeting (MDT).     

Review: Pathology and Its Clinical Relevance of Mucinous Appendiceal Neoplasms and Pseudomyxoma Peritonei

Until recently, many classifications existed for the terminology and histopathologic classification of appendiceal mucinous neoplasms, mucinous appendiceal adenocarcinomas, and pseudomyxoma peritonei (PMP). A major accomplishment was achieved by consensus-based histopathologic classifications on behalf of the Peritoneal Surface Oncology Group International regarding mucinous appendiceal tumours and PMP. As different classifications were used over the years and also owing to the rare nature of these tumors, many clinicians are not familiar with the terminology and the impact on patient management. Hence, an overview concerning mucinous appendiceal neoplasms, mucinous appendiceal adenocarcinomas, and PMP is provided to serve as an introduction into the basic morphology of these tumors with tentative recommendations for management.     

Can low grade PMP be divided into prognostically distinct subgroups based on histological features? A retrospective study and the importance of using the appropriate classification

Introduction

The pathological classification of PMP of appendiceal origin has prognostic and treatment implications. Our goals were to? Classify low grade mucinous carcinoma peritonei (LGMCP) into prognostically distinct subgroups based on histological features.? Compare the reproducibility of the WHO and the PSOGI classifications for both PMP and the appendiceal primary tumor.

Cytoreductive surgery and perioperative intraperitoneal chemotherapy for peritoneal carcinomatosis from colorectal carcinoma: non-mucinous tumour associated with an improved survival

AIMS: Cytoreductive surgery combined with perioperative intraperitoneal chemotherapy has been reported as a treatment option for patients with peritoneal carcinomatosis from colorectal carcinoma. METHODS: Thirty patients with colorectal peritoneal carcinomatosis underwent cytoreductive surgery and perioperative intraperitoneal chemotherapy. All appendiceal cancers were excluded. All patients were followed until January 2006 or death. Univariate analysis was performed to evaluate significant prognostic factors for overall survival, defined from the time of surgery. RESULTS: There were 13 male patients. The mean age at the time of surgery was 54years. There was no hospital mortality. The mean duration of hospital stay was 27days. The overall median survival was 29months, with 1- and 2-year survival of 72% and 64%, respectively. Twenty-one patients had complete cytoreduction and their 1- and 2-year survival rates were 85% and 71%, respectively. Univariate analysis demonstrated that patients with non-mucinous colorectal adenocarcinoma, Peritoneal Cancer Index (PCI) < or =13, and complete cytoreduction were associated with an improved survival. CONCLUSIONS: This study reported on 30 patients who underwent cytoreductive surgery and perioperative intraperitoneal chemotherapy for colorectal peritoneal carcinomatosis. Patients with mucinous tumour had relatively more extensive intraperitoneal disease. Non-mucinous colorectal adenocarcinoma, PCI < or =13, and complete cytoreduction were associated with an improved survival.     

Pseudomixoma peritoneal tipo adenomucinosis peritoneal diseminada con imágenes radiológicas atípicas

Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management.     

Immunotoxin targeting EpCAM effectively inhibits peritoneal tumor growth in experimental models of mucinous peritoneal surface malignancies

Cytoreductive surgery and intraperitoneal (i.p.) chemotherapy constitute a curative treatment option in mucinous peritoneal surface malignancies of intestinal origin, but treatment outcome is highly variable and the search for novel therapies is warranted. Immunotoxins are attractive candidates for targeted therapy in the peritoneal cavity because of direct cytotoxicity, distinct mechanisms of action and tumor cell selectivity. The MOC31PE immunotoxin targets the tumor‐associated adhesion protein EpCAM (Epithelial Cell Adhesion Molecule), and has been administered safely in early clinical trials. In our work, the efficacy of i.p. administration of MOC31PE alone and together with mitomycin C (MMC) was investigated in unique animal models of human mucinous peritoneal surface malignancies. In initial model validation experiments, clear differences in efficacy were demonstrated between MMC and oxaliplatin, favoring MMC in five investigated tumor models. Subsequently, MOC31PE and MMC were given as single i.p. injections alone and in combination. In the PMCA‐2 model, moderate growth inhibition was obtained with both drugs, while the combination resulted in at least additive effects; whereas the PMP‐2 model was highly sensitive to both drugs separately and in combination and intermediate sensitivity was found for the PMCA‐3 model. Furthermore, results from ex vivo experiments on freshly obtained mucinous tumor tissue from animals and patients suggested that classic mechanisms of immunotoxin activity were involved, i.e., inhibition of protein synthesis and induction of apoptosis. The present results suggest that adding MOC31PE to MMC‐based i.p. chemotherapy should be further explored for EpCAM‐expressing peritoneal surface malignancies, and a phase I trial is in preparation.     

卵巢来源腹膜假黏液瘤临床病理分析

  目的  探讨卵巢来源腹膜假黏液瘤（pseudomyxoma peritonei,PMP）的临床病理学特征及免疫组织化学表型。  方法  回顾性分析2010年1月至2019年1月272例于首都医科大学附属北京世纪坛医院确诊为PMP患者的临床资料,研究PMP肿瘤来源,复阅病理切片并行免疫组织化学标记,标记抗体包括CK7、CK20、CEA、Villin、CDX2、SATB2、CA125、ER、PR、PAX8、MUC1、MUC2等。  结果  272例PMP中阑尾来源245例（90.1%）、非阑尾来源27例（9.9%）。卵巢来源PMP仅5例（1.8%）,其中4例为黏液性囊腺瘤、1例为交界性黏液性囊腺瘤,均发生在单侧,5例中2例合并成熟性囊性畸胎瘤;腹膜播散肿瘤中2例为无细胞性黏液、2例为低级别腹膜黏液癌、1例为高级别腹膜黏液癌。免疫组织化学法检测显示,5例PMP患者组织中CK20、CEA、Villin、CDX2均阳性,2例黏液性囊腺瘤合并畸胎瘤患者的SATB2部分阳性、2例SATB2阴性、1例SATB2灶状阳性。  结论  卵巢来源PMP罕见,需对阑尾全部取材或对可疑组织块行连续切片,以排除阑尾黏液性肿瘤,并结合临床症状体征、影像学表现、手术所见、组织学特征及免疫组织化学法检测进行综合分析。      

Intraperitoneal cancer dissemination: mechanisms of the patterns of spread

BACKGROUND: Well known patterns govern the distribution of hematogenous and lymphatic metastasis of cancer. In the past the distribution of cancer cells free within abdominal cavity received little attention and was thought to be a random event. However, surgical observation led the authors to generate and test hypotheses regarding patterns of spread that vary with tumor type, with the intraperitoneal environment, and with the physiology of the peritoneal surface tissues. METHODS: The distribution and volume of peritoneal surface malignancy was prospectively recorded in 129 patients with 5 different types of tumors at the time of cytoreductive surgery. The malignancies studied included pseudomyxoma peritonei (PMP) of appendiceal origin, colonic mucinous adenocarcinoma (MA), nonmucinous colonic adenocarcinoma (NMA), ovarian carcinoma (OV) and sarcoma (SA). The abdominal and pelvic cavity was divided into 3 horizontal sectors, 9 regions and 25 sites. The incidences of tumor implants in these designated areas were statistically analyzed for each tumor type and comparisons between tumor types studied. RESULTS: The magnitude of intraperitoneal cancer dissemination was similar for mucinous tumors, including PMP and MA and significantly higher than for non-mucinous tumors. Also the mucinous cancers were more likely to be present in the upper horizontal sector than were non-mucinous. When NMA was compared to PMP and MA the epigastric region was significantly less likely to contain tumor. For all cancer diagnoses the colon, greater omentum and cul-de-sac of Douglas were most often affected. The ileocecal valve region was more likely to have large tumor masses on its surface than small bowel surface or small bowel mesentery. CONCLUSIONS: Peritoneal carcinomatosis had a wider distribution when mucinous fluid was present; this cancer distribution by intraperitoneal fluid hydrodynamics occurred regardless of histologic aggressiveness. The organs that have peritoneal fluid resorption (omentum and omental appendages) have a high incidence of implants. Small bowel and its mesentery free to move by peristalsis had a reduced incidence of implants as compared to the ileocecal area, which is fixed to the retroperitoneum. These observations may facilitate efforts to treat peritoneal surface malignancy.