Treatment patterns and outcomes in goblet cell carcinoid tumors of the appendix

BACKGROUND

Goblet cell carcinoid (GCC) tumors of the appendix are a rare malignancy. We aim to examine the overall survival per stage and the relationship between different treatment modalities and outcomes for patients with GCC tumors of the appendix.

METHODS

We identified patients with GCC tumors of the appendix from the National Cancer Database. The main outcome was overall patient survival and cox proportional hazard models were used to ascertain predictors of survival.

RESULTS

There were 2552 patients identified. The median age of diagnosis was 57 (interquartile range: 49-65) and 52.3% of patients were female. The 5-year survival for Stage I disease was 91.1% (95% confidence interval [CI]: 82.2%-95.7%), for Stage II disease was 90.5% (95% CI: 85.8%-93.7%), for Stage III disease was 57.0% (95% CI: 45.0%-67.3%), and for Stage IV disease was 18.9% (95% CI: 9.3%-31.0%). In a Cox proportional hazard model, older age (hazard ratio [HR]: 1.1; 95% CI: 1.03-1.12; P < .001), lymph node metastasis (HR: 6.9; 95% CI: 2.76-17.01; P < .001), and positive surgical margins (HR: 2.9; 95% CI:1.13-7.26; P = .003) were associated with worse overall survival for Stages I to III disease while only older age (HR: 1.03; 95% CI: 1.002-1.06; P = .04) was associated with worse overall survival for Stage IV disease.

CONCLUSIONS

Patients with GCC tumors of the appendix who have the nonmetastatic disease have a high 5-year survival. We have identified several prognostic factors for GCC.

Laparoscopic treatment of cystadenocarcinoma of the appendix penetrating in the sigmoid colon

Adenocarcinoma of the vermiform appendix is a rare neoplasm of the gastrointestinal tract that most commonly presents as right lower abdominal pain, mimicking acute appendicitis. Presentation caused by loco-regional spread with involvement of adjacent structures is rare. An accurate and complete preoperative diagnosis has been rare in the past; however, modern imaging techniques allow recognition of most complications and associated conditions. The diagnosis is confirmed postoperatively. Aggressive surgical management is the treatment of choice in appendicular adenocarcinoma. We report the case of appendicular mucinous cystadenocarcinoma in a 55-year-old lady with penetration of the sigmoid colon treated with laparoscopic-assisted sigmoid and en block right hemicolectomy. It was possible to manage this complex case by using a laparoscopic procedure with all the known benefits of minimally invasive surgery.

Landscape of Genetic Mutations in Appendiceal Cancers

In appendiceal cancers, the most frequently mutated genes are (i) KRAS, which, when reactivated, restores signal transduction via the RAS-RAF-MEK-ERK signaling pathway and stimulates cell proliferation in the early stages of tumor transformation, and then angiogenesis; (ii) TP53, whose inactivation leads to the inhibition of programmed cell death; (iii) GNAS, which, when reactivated, links the cAMP pathway to the RAS-RAF-MEK-ERK signaling pathway, stimulating cell proliferation and angiogenesis; (iv) SMAD4, exhibiting typical tumor-suppressive activity, blocking the transmission of oncogenic TGFB signals via the SMAD2/SMAD3 heterodimer; and (v) BRAF, which is part of the RAS-RAF-MEK-ERK signaling pathway. Diverse mutations are reported in other genes, which are part of secondary or less critical signaling pathways for tumor progression, but which amplify the phenotypic diversity of appendiceal cancers. In this review, we will present the main genetic mutations involved in appendix tumors and their roles in cell proliferation and survival, and in tumor invasiveness, angiogenesis, and acquired resistance to anti-growth signals.

Occult appendix pathology in patients undergoing colorectal cancer resection and prophylactic appendectomy

BACKGROUND

The risk-benefit balance of prophylactic appendectomy in patients undergoing left colorectal cancer resection is unclear. The aim of this report is to assess the proportion of histologically abnormal appendices in patients undergoing colorectal cancer resection in a unit where standard of care is appendectomy, with consent, when left-sided resection is performed.

METHODS

A retrospective study on a prospectively collected database was conducted in a single tertiary-care center. Overall, 717 consecutive patients undergoing colorectal cancer resection between January 2015 and June 2021 were analyzed. The primary outcome was the proportion of histologically abnormal appendix specimens at prophylactic appendectomy. The secondary outcome was complications from prophylactic appendectomy.

RESULTS

Overall, 576/717 (80%) patients had appendectomy at colorectal cancer surgery. In total, 234/576 (41%) had a right-/extended-right hemicolectomy or subtotal colectomy which incorporates appendectomy, and 342/576 (59%) had left-sided resection (left-hemicolectomy, anterior resection or abdominoperineal excision) with prophylactic appendectomy. At definitive histology, 534/576 (92.7%) had a normal appendix. The remaining 42/576 (7.3%) showed abnormal findings, including: 14/576 (2.4%) inflammatory appendix pathology, 2/576 (0.3%) endometriosis, 8/576 (1.4%) hyperplastic polyp, and 18/576 (3.1%) appendix tumors, which encompassed six low-grade appendiceal mucinous neoplasms (LAMNs), three carcinoids, and nine serrated polyps. In the 342 patients who had prophylactic appendectomy, 10 (2.9%) had a neoplasm (two LAMN, three carcinoids, and five serrated polyps). There were no complications attributable to appendectomy.

CONCLUSION

Occult appendix pathology in patients undergoing colorectal cancer resection is uncommon when prophylactic appendectomy was performed. However, approximately 3% of patients had a synchronous appendix neoplasm.