Prostate cancer with an unusual metastatic affinity for the appendix, inducing acute appendicitis

Abstract

Acute appendicitis induced by metastatic disease is uncommon. We present the case of an 82-year-old man with known bony metastases secondary to prostatic cancer who presents with a short history of acute abdominal pain. A CT scan was indicative of acute appendicitis and the patient underwent a laparoscopic appendicectomy; a phlegmonous mass seen intraoperatively was suspicious for malignancy, and histopathology confirmed acute appendicitis as well as metastases of prostate cancer. Metastatic disease should be considered as an important differential in all patients with a known history of malignancy, as this may in turn complicate their presenting surgical complaint.

Prostate cancer metastasis mimicking appendicitis—A rare but important differential diagnosis in PET/CT imaging

“…Only a small percentage of disseminated prostate cancer shows metastasis in the digestive system or the peritoneum, [1] and even more uncommonly carcinomatosis in relation to the appendix. In all previously reported cases of prostatic metastasis in the appendix, the patients presented with acute appendicitis and had an appendectomy performed from which metastasis was confirmed through histopathological assessment of the surgical specimen [ [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] ]. Acute appendicitis is found to be the most frequent initial manifestation of appendiceal tumors, seen in 30%-50% of patients [15] .…”

“…These image findings could equally come as a result of the extension of the metastasis or from a superimposed appendicitis [15] . Preoperative CT scans from previously reported cases of acute appendicitis secondary to prostate cancer metastasis predominantly show dilated appendix, periappendicular stranding and/or wall thickening [ 2 , [3] , [4] , [5] , [6] , 7 , [8] , [9] , [10] ]. Christou et al present a patient with an identical initial staging and Gleason score to the patient in the present report [2] .…”

“…Preoperative CT scans from previously reported cases of acute appendicitis secondary to prostate cancer metastasis predominantly show dilated appendix, periappendicular stranding and/or wall thickening [ 2 , [3] , [4] , [5] , [6] , 7 , [8] , [9] , [10] ]. Christou et al present a patient with an identical initial staging and Gleason score to the patient in the present report [2] . Their patient had an elongated and dilated appendix on CT imaging as well but differed in symptomology by presenting with lower quadrant abdominal pain [2] .…”

“…Carcinomatosis in relation to the appendix is even more uncommon and not well described in the literature. To the best of our knowledge, only 11 cases of prostate cancer with a metastatic affinity for the appendiceal tissue have been reported worldwide, all located in the appendiceal lumen [ [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] ].…”

Metastatic prostate adenocarcinoma and high-grade appendiceal mucinous neoplasm mimicking acute appendicitis in a post-radiation therapy patient

“…10 There have been case reports of metastatic prostate cancer Metastatic prostate adenocarcinoma and high-grade appendiceal mucinous neoplasm mimicking acute appendicitis in a post-radiation therapy patient presenting as acute appendicitis; however, it is an extremely uncommon occurrence with only 1%-2% of metastatic prostate cancer presenting as acute appendicitis. [11][12][13][14] Acute appendicitis is the most common surgical emergency of the abdomen in the United States, with a lifetime incidence of 8.6% in men and 6.7% in women. Although currently uncertain, the pathophysiology of acute appendicitis has been hypothesized to involve obstruction of the appendiceal lumen, resulting in ischemia and secondary bacterial infection of the appendiceal wall.…”