Complete Cytoreductive Surgery vs. Debulking Surgery for pseudomyxoma peritonei of appendiceal origin: A propensity score-matched study based on a single-center experience

Pseudomyxoma peritonei originating from small intestine: A case report and review of literature

BACKGROUND

Pseudomyxoma peritonei (PMP) is a distinct form of peritoneal malignancy characterized by diffuse intra-abdominal gelatinous ascites, with an estimated incidence of 1-3 per 1000000. PMP is predominantly secondary to appendiceal mucinous neoplasms, with rarer origins including the ovaries, colon, and urachus. However, PMP originating from small intestine is extremely rare.

CASE SUMMARY

A 60-year-old male patient presented with anorexia and abdominal distension. Computed tomography revealed the presence of abdominopelvic effusions and multiple intra-abdominal space-occupying lesions. Ultrasound-guided aspiration indicated that the aspirated tissue was mucinous. Exploratory laparoscopy and tissue biopsy identified diffuse tumor nodules in peritoneum, omentum, pelvic region, intestinal walls, and mesentery. Histopathological analysis of the resected tumors confirmed the presence of mucinous adenocarcinoma, but the primary lesion was difficult to determine. The patient was referred to our center for further treatment and underwent cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) under general anesthesia. The intraoperative peritoneal cancer index was 30. The surgery lasted 8 hours, with a blood loss of about 600 mL. A complete cytoreduction (CCR0) was achieved. No serious complications occurred after surgery, and the patient's condition was good during the telephone follow-up. Postoperative pathology confirmed the diagnosis of small intestinal mucinous adenocarcinoma at proximal jejunum, which was complicated by high-grade PMP.

CONCLUSION

PMP originating from small intestine is an exceptionally rare entity that exhibits non-specific clinical features. The preferred treatment is CRS + HIPEC.

Negative Impact of Systemic Therapy on Survival in Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Low-Grade Metastatic Appendiceal Adenocarcinoma

BACKGROUND

Despite studies demonstrating that patients with peritoneal metastases from low-grade appendiceal adenocarcinoma (AA) do not respond well to systemic chemotherapy (SC), patients frequently undergo combination of SC with cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) regardless of grade.

METHODS

A nationwide retrospective analysis using the National Cancer Database evaluated patients with AA with peritoneal metastasis from 2016 to 2021. Cox proportional hazards model was used to evaluate the impact of SC in addition to CRS/HIPEC on overall survival (OS) stratified by tumor grade.

RESULTS

A total of 1,449 patients were included: 481 low-grade, 428 intermediate-grade, and 540 high-grade tumors. Clinical variables, such as age, sex, and comorbidity index, were similar across tumor grades. Cytoreductive surgery/hyperthermic intraperitoneal chemotherapy without SC was utilized in 65.73% of low-grade cases compared with 41.01% in intermediate-grade and 11.11% in high-grade cases. Systemic chemotherapy was utilized alone in 17.74% and with CRS/HIPEC in 16.53% of low-grade cases. In adjusted survival analysis, addition of SC to CRS/HIPEC was associated with worse OS for patients with low-grade AA (hazard ratio [HR] 2.77, 95% confidence interval [CI] 1.18-6.50) but not for intermediate (HR 1.65, 95% CI 0.82-3.35) and high-grade tumors (HR 1.18, 95% CI 0.67-2.45). The addition of time to definitive surgery variable nullified the negative impact of adding SC to CRS/HIPEC in low-grade AA (HR 1.76, 95% CI 0.68-4.53).

CONCLUSIONS

Negative OS impact of SC may be mediated by delays in effective surgical/intraoperative therapy. If CRS/HIPEC is planned for patients with metastatic low-grade AA, avoiding SC may facilitate earlier surgical intervention and improve survival.

Prophylactic cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for low-grade appendiceal mucinous tumors with early and limited disease after completely removed

The necessity of prophylactic cytoreductive surgery (PCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for low-grade appendiceal mucinous neoplasms (LAMN) after complete removal is still controversial. This study aims to determine the role of PCRS + HIPEC and identify optimal strategies for managing these patients. One hundred fifty-nine patients who sought medical advice at Aerospace Center Hospital were retrospectively analyzed from January 2011 to December 2021. All the patients were divided into the PCRS group and the observation group. The data of surgical specimens and pathology was collected, and the effect on recurrence-free survival (RFS) was analyzed. Of these 159 patients, 88 were in the PCRS group, and 71 were in the observation group. The median follow-up time was 38 months. Seven patients recurred and developed into pseudomyxoma peritonei, 1 in the PCRS group and 6 in the observation group. The analysis of RFS showed that patients who underwent PCRS (P = .01) and HIPEC (P = .01) had better survival. After multivariate analysis, the surgical specimen accompanied by disseminated peritoneal adenocarcinoma was identified as an independent prognostic factor for RFS. In the study of surgical resection content, patients with greater omentum (P = .01) and bilateral fallopian tubes and ovaries of women (P = .002) resection had a more prolonged RFS with statistical significance. The research indicated that PCRS + HIPEC could prevent recurrence. Therefore this treatment were necessary for LAMN after complete removal in patients with a high risk of recurrence. However, it was not proven to be an independent factor for RFS, and a multicenter, prospective, randomized trial was need to definitively address the role of PCRS + HIPEC for LAMN after complete resection.

Two-stage cytoreductive surgery for 'extensive' pseudomyxoma peritonei: A legitimate alternative or salvage strategy?

BACKGROUND AND AIM

Two-stage cytoreductive surgery (CRS) has been proposed as an alternative to one-stage surgery in patients who have 'extensive' pseudomyxoma peritonei (PMP) and/or are unfit for very extensive surgery, to reduce morbidity. We review current evidence on two-stage CRS focusing on patient selection, interval between procedures, extent of surgery, use of HIPEC, perioperative and oncological outcomes.

METHODS

This is a narrative review. A literature search on PubMed and Embase was performed using keywords- 'Two-stage cytoreductive surgery', 'pseudomyxoma peritonei', 'high-volume PMP', 'huge PMP', 'cytoreductive surgery', 'HIPEC', 'staged surgery' and 'extensive pseudomyxoma peritonei'.

RESULTS

Five studies reported outcomes in a total of 114 patients. The indications for two-stage CRS were: in two studies, patients undergoing an incomplete cytoreduction due to undue surgical risk were reevaluated for a second surgery during routine surveillance; severe comorbidities in one; extensive disease with PCI>28 in another and in one, only HIPEC was performed as a second procedure due to intraoperative hemodynamic instability (the two-stage procedure was performed in interest of patient's safety). Major morbidity ranged from 0 to 37.5 % (first-stage) and 25%-38.9 % (second-stage). Short term follow-up demonstrated equivalent short-term oncological outcomes compared to historical data. Long term follow-up and quality-of-life data were not available.

CONCLUSIONS

The published studies showed different interpretations and applications of the two-stage CRS concept. The reported morbidity was similar to that after single-stage CRS for extensive PMP. Though short-term survival outcomes are acceptable, long-term follow-up is needed. Planned two-stage CRS should currently be reserved for highly selected clinical situations.

Successful treatment of pseudomyxoma peritonei (PMP) through cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC): A case report and literature review

INTRODUCTION AND IMPORTANCE

Pseudomyxoma peritonei (PMP) is characterized by the accumulation of mucinous fluid in the abdominal cavity, typically originating from mucin-producing tumors, most commonly arising in the appendix.

CASE PRESENTATION

A 63-year-old male patient presented to the hospital with complaints of abdominal pain, significant weight loss, a palpable mass in the right iliac fossa, and evidence of ascites. A diagnosis of PMP was proposed based on findings from a computed tomography (CT) scan, which was subsequently confirmed through histopathological examination of a biopsy. The patient underwent successful treatment with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS-HIPEC).

CLINICAL DISCUSSION

Diagnosing PMP presents challenges due to its rarity and the potential for extensive spread throughout the peritoneal cavity, necessitating a multidisciplinary approach for successful treatment.

CONCLUSION

Pseudomyxoma peritonei is a rare yet medically significant condition. Documenting a case of this ailment in Palestine has the potential to advance medical understanding, raise awareness, and improve patient care standards within the local healthcare system. By documenting this uncommon condition, healthcare practitioners in Palestine can gain valuable insights into its manifestations, diagnostic processes, and treatment modalities. This contribution not only enriches the global medical literature but also promotes collaboration in addressing the challenges associated with rare diseases.

[Incidental finding of appendiceal mucinous neoplasms]

Low-grade appendiceal mucinous neoplasms (LAMN) are rare and are diagnosed in at least 0.13% of appendectomies in Germany, although significant underreporting is likely. Perforation of the tumors can result in abdominal mucinous collections, so-called pseudomyxoma peritonei (PMP). The challenge in the treatment of LAMN is the adequate approach to the incidental finding of these tumors. If a mucinous neoplasm is preoperatively suspected in cases of an acute condition, usually appendicitis, it must be weighed up whether a conservative approach is justifiable or whether immediate appendectomy is necessary. If this is the case, an intraoperative perforation of the appendix must be avoided and the complete abdominal cavity must be inspected for mucin deposits. If conservative treatment is possible, further treatment should take place at a specialized center. If the neoplasm is first found incidentally during surgery, perforation of the appendix should also be avoided and the entire abdominal cavity should be inspected for a PMP. If a PMP is present cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) should be performed in a specialized center. If LAMN are found during the postoperative histological work-up, it should be evaluated whether a perforation was present and mucin collections are noted in the surgical report. In the case of LAMN without evidence of a PMP, appendectomy is the adequate treatment. In cases of intra-abdominal mucinous collections, samples should be taken and further treatment should be performed at a center with sufficient expertise. An ileocecal resection or oncological hemicolectomy is not indicated. After adequate treatment, all patients should receive a follow-up using cross-sectional imaging (preferably magnetic resonance imaging, MRI) and determination of the tumor markers CEA, CA 19-9 and CA 125.

Combined ultrasonography and CT for prognosis and predicting clinical outcomes of patients with pseudomyxoma peritonei

OBJECTIVES

This study aimed to identify the diagnostic accuracy of combined ultrasonography (US) and computed tomography (CT) in evaluating the tumor burden of pseudomyxoma peritonei (PMP). Besides, we assessed the ability of this combination to predict the likelihood of complete resection.

METHODS

This retrospective study involved 504 patients diagnosed with PMP and scheduled for cytoreduction surgery. We compared tumor burden-quantified as peritoneal cancer index (PCI) by preoperative US and CT (US-CT-PCI)-with surgical findings. Next, we assessed the prognostic value of US-CT PCI and imaging features in determining the completeness of cytoreduction (CCR) score using multivariate analysis.

RESULTS

US-CT PCI demonstrated a high PCI evaluation accuracy under moderate tumor burden. Higher US-CT PCI could predict incomplete resection. In addition, we identified imaging features such as mesenteric involvement as an independent predictor of incomplete resection (hazard ratio (HR) = 2.006; p = 0.007).

CONCLUSIONS

US-CT PCI allowed us to predict the completeness of cytoreductive surgery in patients with PMP. Moreover, the combined US and CT imaging detected several features indicating incomplete cytoreduction.

KEY POINTS

• Ultrasonography (US) can act as a complementary diagnostic modality in peritoneal cancer index (PCI) evaluation by combining CT in the small bowel area and US in the abdominal area. • A modified peritoneal cancer index (US-CT PCI) helps preoperatively evaluate tumor burden with high accuracy and allows to predict incomplete resection. • US-CT PCI of 20 or above and the involvement of particular structures such as mesentery, independently indicate incomplete resection.

Prognostic prediction of preoperative nutritional status in low-grade appendiceal mucinous neoplasms

To describe the preoperative nutritional status of Low-grade Appendiceal Mucinous Neoplasms (LAMNs) and identify prognostic factors for survival. Medical records from 165 patients with LAMNs who attended the Aerospace Center Hospital, Beijing, China between January 2017, and December 2018 were retrospectively reviewed. Survival analysis was performed with the Kaplan-Meier method, the log-rank test, and a Cox proportional hazards model. Among 165 patients, 59 (36%) were male and 106 (64%) were female. Patient's median age was 58 years (range 20 to 78 years). Univariate analysis indicated that gender, weight loss, prior surgical score (PSS), red blood cell, albumin, peritoneal cancer index (PCI), completeness of cytoreduction (CCR), and hyperthermic intraperitoneal chemotherapy (HIPEC) were related to prognosis. Multivariate analysis showed that PSS, CCR and HIPEC were independent predictors of prognosis. The preoperative nutritional status of patients plays an important role in predicting prognosis. Patients can benefit from a complete cytoreductive surgery (CCRS) and HIPEC in an experienced institution for the first medical treatment.

Nomogram to predict overall survival of patients with pseudomyxoma peritonei of appendiceal origin: A retrospective cohort study

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare disease, with the rate of overall survival (OS) influenced by many factors. The present study aimed to define independent predictors and establish a nomogram for individual risk prediction in PMP patients.

METHODS

One hundred forty-seven PMP patients were consecutively included between June 1, 2013, and November 22, 2019. The log-rank test was used to compare the OS rate between groups; subsequently, variables with p < .10 were subjected to multivariate Cox modeling for defining independent prediction indicators. Finally, a nomogram was established based on independent prognosticators and assessed for internal validation.

RESULTS

Multivariate Cox analysis showed that D-dimer level, carbohydrate antigen (CA) 125 level, CA 19-9 level, degree of radical surgery, and histological grade were all independently associated with OS in PMP patients. A nomogram was plotted and underwent internal validation. The discrimination ability of the nomogram revealed a good predictive ability as indicated by the C-index value (0.825), and calibration plots confirmed good consistency between the predicted and observed survival probabilities.

CONCLUSIONS

Five independent prognostic factors for predicting the survival of PMP patients were identified, and the nomogram based on these independent indicators showed a reasonable discrimination ability for individual risk prediction.