The incidence of appendectomies, tonsillectomies and adenoidectomies in cancer patients

Appendicitis as an early manifestation of subsequent malignancy: an asian population study

BACKGROUND & AIMS

Cancer risk after appendectomy in patients with appendicitis remains unclear. This study examined the role of appendicitis as an early manifestation harbingering the distant malignancy.

METHODS

From the insurance claims data of Taiwan, we identified a cohort of 130,374 patients newly received appendectomy from 2000-2009, without cancer diagnosis. A comparison cohort of 260,746 persons without appendectomy and cancer was selected from the same database, frequency matched by age, sex, comorbidity and index year. We monitored subsequent cancers with a12-month follow-up.

RESULTS

Over all, 1406 and 616 cancer cases were identified in the appendectomy cohort and comparisons, respectively, with all cancers incidence rate 4.64-fold higher in the appendectomy cohort (9.06 vs. 1.96 per 1000 person-months). Digestive and female genital organs harbored 80.9% of cancer cases in the appendectomy cohort. The Cox model measured site-specific hazard ratio (HR) was the highest for female genital cancers (23.3), followed by cancers of colorectum (14.7), small intestine (10.1), pancreas (7.40), lymphoma (5.89) and urinary system (4.50), all significant at 0.001 level. The HR of all cancers decreased from 13.7 within 3 months after appendectomy to 1.37 in 7-12 months after the surgery. In general, relative to the comparison cohort, younger appendectomy patients tended to have a higher HR than older patients.

CONCLUSIONS

The high incident cancers identified soon after appendectomy suggest the acute appendicitis is the early sign of distant metastatic malignancy. The risk of colorectal cancer, female genital cancer and haemopoietic malignancy deserve attention.

Appendectomy and cancer risk in Jewish BRCA1 and BRCA2 mutation carriers

Previous studies suggested that appendectomy may affect cancer risk in the general population. No data on the effect of appendectomy on cancer risk in BRCA1 and BRCA2 carriers is available. Data on appendectomy, cancer type, and age at diagnosis were collected from BRCA1 (n = 677) and BRCA2 (n = 270) female Jewish Israeli mutation carriers counseled in a single medical center. Data were also collected on 225 consecutive ovarian cancer cases treated at the same medical center. Overall, 367/947 (38.7%) of mutation carriers had breast cancer (age at diagnosis 44.1 ± 10.4 years), 142 (15.0%) ovarian cancer (53.6 ± 10.1 years), and 438 (46.25%) were asymptomatic carriers (age at counseling 41.4 ± 11.2 years). Mean age at diagnosis of consecutive ovarian cancer cases was 53.6 ± 10.1 years. Of mutation carriers, 28/367 breast cancer cases (7.6%), 15/142 ovarian cancer cases (10.6%), and 11/438 asymptomatic carriers (2.5%) underwent prior appendectomy (P = 0.001 for breast/ovarian cancer when compared with asymptomatic carriers). In all but two cases, appendectomy was performed more than 10 years before cancer diagnosis or age at counseling. Of ovarian cancer patients, 12/225 (5.3%) underwent appendectomy, and in 10 appendectomy was performed 10 years or more before ovarian cancer diagnosis (P = 0.068 when compared with inherited ovarian cancer cases). This study suggests that prior appendectomy is more frequently noted in BRCA1 and BRCA2 carriers with breast and ovarian cancer than in unaffected mutation carriers. The mechanism for this association is elusive, and future analyses of ethnically diverse mutation carriers are needed to validate these results.

Appendectomy and subsequent cancer risk

Although earlier epidemiologic studies reported a positive association between appendectomy and certain cancers, interest was limited due to lack of confidence in the study findings. However, recent morphologic studies on the immune structure of the vermiform appendix in the rabbit and man argue for a reevaluation of the appendectomy--cancer association. This paper reviews briefly the morphologic and epidemiologic literature on the subject to date. The validity of the earlier epidemiologic findings is discussed and avenues for further research assessing the relationship of appendectomy to subsequent cancer risk are proposed.

Rationale of incidental appendectomy

In an effort to settle the controversy regarding use of incidental appendectomy, we have reviewed the literature regarding the function of the appendix and its role in the development of cancer, incidence of acute appendicitis, pathologic findings in incidentally removed appendices, and morbidity of incidental appendectomy. Considering all parameters we conclude that incidental appendectomy is a service to the patient and should be done except where specifically contraindicated.

Appendectomy, tonsillectomy, and neoplasia

Reports in the literature that study the frequency of cancer in individual who have had their tonsils or appendix or both removed are reviewed. Some investigators found a high incidence of solid cancers - in particular, breast and colon neoplasms - in female patients who have had appendectomy, but others disagreed. The association of tonsillectomy and/or appendectomy with the later development of malignant lymphomas is not proven.