Reply to Krüger et al.: Intramucosal Adenocarcinoma of the Appendix

We are grateful to Krüger et al. for their interest in our article [1]. Their report is quite interesting and suggestive. As Nitecki et al. reported, second primary malignancies were encountered in 35 % of patients with surgically treated primary adenocarcinoma of the appendix and synchronous lesions in 18 % - usually in the large intestine (59 %), as well as the pancreas, ovary, uterus, breast, kidney, prostate, and lung [2]. This incidence of secondary neoplasms is much higher than that for colonic cancer in general. In 30 cases of carcinoma metastatic to the appendix reported by Burney et al., the primary lesion was in the breast in 12 cases (40 %), in the lung in five cases, and in the stomach in three cases [3]. In 33 cases reported in Japan, the primary lesion was in the stomach in 25 cases (76 %), in the gallbladder in four cases, and in the lung and breast in two cases each [4]. We diagnosed our case as a primary adenocarcinoma of the appendix firstly because, as shown in Figure 3 in the article, the well-differentiated adenocarcinoma was adjacent to normal glandular structures, and secondly the lesion was an intramucosal adenocarcinoma with no vascular involvement and no metastases to the lymph nodes.

Esophagogastroduodenoscopy, abdominal ultrasonography, abdominal computed tomography, and chest radiography were carried out before surgery, and no synchronous tumors or metastatic lesions were found. We agree with Krüger et al. that a careful search of the lungs and abdominal organs should be made in order to detect synchronous and metastatic lesions as well as a primary tumor. Immunohistochemical staining would be helpful to detect the origin of such metastases.

References

• 1 Sakamoto I, Watanabe S, Sakuma T. et al . Intramucosal adenocarcinoma of the appendix: how to find and how to treat.  Endoscopy. 2003;  35 785-787
• 2 Nitecki S S, Wolff B G, Schlinkert R. et al . The natural history of surgically treated primary adenocarcinoma of the appendix.  Ann Surg. 1994;  219 51-57
• 3 Burney R E, Koss N, Goldenberg I S. Acute appendicitis secondary to metastatic carcinoma of the breast.  Arch Surg. 1974;  108 872-875
• 4 Shimamoto T, Onitsuka A, Katagiri Y. et al . Acute appendicitis secondary to metastatic appendiceal carcinoma from gastric cancer.  J Abdom Emerg Med. 2000;  20 95-99