乌鸦传媒

A 35-year-old man presents to hospital. He has no notable history of illness -- 3 months previously, he had acute appendicitis, for which he had undergone laparoscopic appendectomy. Although the surgery was successful, surgeons noted perforation of the appendix, which upon extraction was observed to be coated in mucin.

Surgical pathology reveals that the patient has a low-grade appendiceal mucinous neoplasm (LAMN); further examination reveals extra-appendiceal mucin at the resection margin, and acellular mucin invading the visceral peritoneum and involving the proximal surgical margin. The mesenteric resection margin also contains acellular mucin; surgeons note the presence of acute appendicitis.

Investigations include tests for tumor markers and computerized tomography (CT) scans. Serum level of carcinoembryonic antigen (CEA) is 1.160 ng/mL, CA 19-9 was sent for but the tracer reagent was not available.

Findings of CT scans of the chest, abdomen, and pelvis are unremarkable, with no evidence of disease. After consultation with the tumor board and with the informed consent of the patient, the clinicians schedule cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC).

Following administration of general anesthesia, surgeons make a 5.5-cm periumbilical incision, extended to allow access to the intra-abdominal cavity, and they insert a single gel port.

The abdomen was able to be fully assessed via several approaches: direct laparoscopic inspection, direct examination through the single incision, and via hand palpation of the area behind the liver.

Findings during the operation include tumor deposits in the rectovesical pouch and right upper-quadrant abdominal wall, which surgeons dissect and remove. They also note the presence of mucin at the base of the appendix.

Several lesions are identified as follows using the camera scope and palpation:

• The right lower quadrant has evidence of disease at the base of the cecum (peritoneal cancer index [PCI] score 2)

• A single nodule is noted in the rectovesical pouch (PCI score 1)

• A single nodule is found in the right upper quadrant (PCI score 1)

The patient's total PCI score, therefore, is 4.

Surgeons perform a partial cecectomy and omentectomy. The patient also receives HIPEC using the Sugarbaker mitomycin C-based regimen, with an intraperitoneal solution of mitomycin C and doxorubicin, both in 2L 1.5 dextrose at a dose of 15 mg/m² and at 42° C. At the same time, the patient is started on an intravenous infusion of 5-fluorouracil (400 mg/m²) and leucovorin (20 mg/m²) for 90 minutes.

There are no complications either during or after the operation. Clinicians follow the Enhanced Recovery After Surgery (ERAS) protocol. The patient resumes intake of fluids by mouth on the night of his surgery, and is discharged to his home 3 days after the surgery.

Case Follow-up

No complications are noted during the 30 days following surgery. The pathology report following surgery includes a positive focus of low-grade mucinous neoplasm at the appendicular stump, with a negative margin, including the cecum wall. One reactive lymph node is found to be negative for malignancy. Likewise, the two peritoneal nodules resected in the right upper and lower quadrants are not found to be malignant.

Discussion

The authors of this case report¹ note that to the best of their knowledge, this is the first CRS and HIPEC performed through a single-port laparoscopic (SPL) approach.

The authors suggest that success with this single-port technique is related to the advantage of direct visualization and hand palpation of the bilateral subphrenic area, allowing for more accurate PCI assessment compared with other minimally invasive surgery (MIS) approaches.

Additional benefits seen in this case include the opportunity to minimize the size and number of incision sites compared with traditional laparoscopy, with the potential to reduce the risk of port-site metastasis.

Approach to Surgery

CRS with HIPEC has evolved since it was developed almost 2 decades ago, and now represents a promising approach to treating incurable and palliative cases of peritoneal carcinomatosis,² the case authors observe.

CRS aims to remove all macroscopically detectable tumor, through either direct resection of tumor parts or complete excision of the involved organ. This is followed by HIPEC, the instillation of heated chemotherapy in the abdominal cavity, to remove residual microscopic disease.³

Various minimally invasive approaches to CRS-HIPEC have been used in recent years, including robotics and laparoscopic hand-assisted techniques.^4-6

Peritoneal Surface Malignancy

Peritoneal surface malignancy is defined as a group of tumors arising from abdominal organs, which can lead to peritoneal carcinomatosis.²

Cancer originating in the appendix is rare, affecting less than 2% of all patients who receive an appendectomy, and 0.4% of all patients with gastrointestinal tract malignancies.⁷

Most cases of appendiceal cancer present as acute appendicitis, although they may also be discovered during surgery for other abdominal diseases.⁷

Adenocarcinoma of the appendix is categorized as colonic or cystic based on the pattern of growth:

• Colonic tumors originate from tubular or tubulovillous adenomas, and follow a course similar to that of colonic adenocarcinomas

• Cystic-type tumors develop as a progression of a cystadenoma on the base of a villus adenoma.^7,8

Mucinous appendiceal neoplasms are among the cystic-type tumors, with mucin-producing cells. About 20% of such patients develop pseudomyxoma peritonei, a rare cancer that is initially asymptomatic.

Disease progression may cause vague, nonspecific symptoms such as undefined abdominal pain or distension, or result in a hernia due to the accumulation of mucin.^2,9

There are four types of mucinous neoplasms, as classified by the Peritoneal Surface Oncology Group International in 2016:

• LAMN

• High-grade appendiceal mucinous neoplasm

• Mucinous adenocarcinoma

• Poorly differentiated mucinous adenocarcinoma²

The case report authors cite data from a retrospective, multicenter study of CRS-HIPEC outcomes in 1,559 LAMN patients, which identified PCI as the most significant prognostic factor, with 5- and 10-year survival rates of 73% and 93% for patients with PCI of more than 31 and less than 10, respectively.¹⁰

In addition, the extent of cytoreductive resection was strongly associated with survival outcomes, with rates of 91% at 5 years and 81% at 10 years in complete resection. In contrast, patients with incomplete cytoreductive resection and residual disease of more than 2.5 mm had 5- and 10-year survival rates of 33% and 10%, respectively.¹⁰

The patient reported in this case had a low-grade , which clinicians note is defined as low-grade cytologic atypia with extension beyond the mucosa, but without any wall invasion.² The presence of acellular mucin in this patient's tumor is associated with a comparatively better prognosis than other types of mucinous neoplasms.

After a complete abdominal exploration and PCI assessment with direct inspection by the laparoscopic camera, direct visualization, and palpation of bilateral subphrenic area through the single incision, clinicians determined that the patient's PCI was 4.

They note that both the positive margin in the first surgery and the absence of any remnant disease in the preoperative CT scan assessment support the accuracy of the PCI assessment intra-operatively. Thus, the authors chose to use the SPL technique to complete CRS and HIPEC, which was achieved with complete resection.

MIS: Pros and Cons

The expanding use of laparoscopy and MIS in the last 2 decades has had a positive impact on surgeons' experience and skills. The case report authors suggest that numerous published reports of the significance and benefits^4-6 have drawn increasing attention to MIS procedures, compared with the traditional open technique with a midline laparotomy incision.

They nevertheless highlight that the key limitation of MIS in CRS is the challenge of performing a complete abdominal examination, particularly of the two areas behind the liver and spleen¹¹ in order to determine an accurate PCI.

In recurrence of peritoneal metastasis from colorectal cancer, estimation of PCI using laparoscopy failed to identify a peritoneal deposit in 18% of cases, compared with 0% using the laparotomy approach.⁵

Although data are sparse compared with for the traditional open technique, using CRS-HIPEC with a curative intent in selected patients with peritoneal surface malignancies and a low PCI of 10 or less is safe and feasible, and may offer improved short-term results and outcomes, including a reduced postoperative length of stay (i.e., 4 days).^4-6

As well, clinicians' use of an MIS approach and the Enhanced Recovery After Surgery () protocol contributed to an improved postoperative recovery course.

Specific benefits of the ERAS Protocol seen in this patient include the following:

• Avoidance of nasogastric tube insertion

• Early removal of the Foley catheter

• Immediate mobilization

• Early resumption of oral intake

• Adequate analgesia

• Short 3-day postoperative stay

The case authors note that while more prospective studies are needed, single-port laparoscopic CRS-HIPEC has advantages when compared with other MIS approaches such as direct visualization and palpation through the incision, toward more accurate assessment of PCI.

Nevertheless, the team explain, the standard of care continues to be the traditional open technique, which offers the most accurate PCI assessment compared with all MIS approaches.⁵

Based on the case of this patient, the authors conclude that in very select patients with favorable condition, and limited disease based on preoperative histopathology and radiological study, the single-port approach is safe and feasible, with a positive short-term outcome, better patient recovery, and a shorter hospital stay.

References

1. Turki A, et al: Single-Port Laparoscopic Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy. Am J Case Rep 2019; 20: 1648-1651.

2. Bartlett DJ, et al: Mucinous appendiceal neoplasms: Classification, imaging, and HIPEC. Abdom Radiol (NY) 2019; 44(5): 1686–1702.

3. Foster JM, et al: Morbidity and mortality rates following cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy compared with other high-risk surgical oncology procedures. JAMA Netw Open 2019; 2(1): e186847.

4. Salti GI, Naffouje SA: Feasibility of hand-assisted laparoscopic cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal surface malignancy. Surg Endosc 2019; 33(1): 52–57.

5. Passot G, et al: Postoperative outcomes of laparoscopic vs. open cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy for treatment of peritoneal surface malignancies. Eur J Surg Oncol 2014; 40(8): 957–962.

6. Gabriel E, et al: Robotic-assisted cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). J Robot Surg, 2018; 13(1): 175–179.

7. Benedix F, et al: Primary appendiceal carcinoma – epidemiology, surgery and survival: Results of a German multi-center study. Eur J Surg Oncol 2010; 36(8): 763–771.

8. Ruoff C, et al: Cancers of the appendix: Review of the literatures. ISRN Oncol 2011; 2011: 728579.

9. Smeenk R, et al: Appendiceal neoplasms and pseudomyxoma peritonei: A population-based study. Eur J Surg Oncol 2008; 34(2): 196–201.

10. Chua TC, et al: Early- and long-term outcome data of patients with pseudomyxoma peritonei from appendiceal origin treated by a strategy of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. J Clin Oncol 2012; 30(20): 2449–2456.

11. Arjona-Sanchez A, et al: A minimally invasive approach for peritonectomy procedures and hyperthermic intraperitoneal chemotherapy (HIPEC) in limited peritoneal carcinomatosis: The American Society of Peritoneal Surface Malignancies (ASPSM) multi-institution analysis. Surg Endosc, 2018; 33(3): 854–860.

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