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PubMed1976

Complement receptor lymphocytes in the rabbit I. an SIg-negative subpopulation in the appendix.

Complement receptor lymphocytes (CRL) were detected in various rabbit lymphoid tissues by the ability of these CRL to form rosettes with sheep red blood cells coated sequentially with rabbit antiserum directed against sheep red blood cell stroma and horse serum as a nonhemolytic source of complement (EAC). The rosette assay was shown to be specific for complement receptor (CR) activity and the EAC capable of detecting both C3b and C3d specific receptors. With lymphocyte preparations containing less than 5% phagocytic cells, the average per cent CRL in the various tissues studied was as follows: thymus 1%, popliteal lymph node 18%, spleen 30%, appendix 35%, and peripheral blood 45%. Double assays in which the lymphocytes were prestained with an FITC-labeled Fab fragment of a goat anti-rabbit Fab antibody before rosetting indicated that CRL were a subpopulation of surface immunoglobulin (SIg)-bearing lymphocytes in popliteal lymph node, spleen, and peripheral blood. In the appendix, however, in addition to finding SIg+ CR+ and SIg+ CR- populations, an SIg- CR+ population was consistently found. Double assays employing FITC-labeled goat antibodies specific for mu, alpha, and gamma determinants were also performed to determine if there was any relationship between the class of Ig displayed and presence of CR. It appeared that an approximately equivalent percentage of both IgM- and IgG-bearing cells also displayed CR. Experiments in which appendix cells were treated with Pronase to remove SIg and CR and the cells cultured in vitro to allow regeneration of surface markers confirmed the existence of SIg+CR+, SIg+CR-, and SIg-CR+ lymphocyte subpopulations. Whether the SIg-CR+, population represents a developing B cell population which will eventually also express SIg or whether it belongs to the T or "null" cell populations is unclear at present.

Animals↗

PubMed2001

Detection of pinpoint tenderness on the appendix under ultrasonography is useful to confirm acute appendicitis.

HYPOTHESIS: Ultrasonography can be efficiently performed using new criteria for the diagnosis of acute appendicitis. DESIGN: Prospective trial. PATIENTS: Eighty-nine patients admitted to the hospital with suspected appendicitis between March 1998 and November 2000. INTERVENTION: At hospital admission, a staff surgeon evaluated each patient and determined whether the patient had appendicitis requiring immediate surgery or another disease. Patients then underwent ultrasonography. A sonographic transducer was placed on the area of maximal tenderness. When the pathological manifestation was depicted, the examiner slipped a fingertip between the transducer and the patient's skin and then pressed the area of depicted pathological manifestation to find pinpoint tenderness. When maximal pinpoint tenderness was noted on the appendix or on pathological manifestations contiguous to the appendix, we diagnosed the condition as appendicitis. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values, and overall accuracy. RESULTS: The diagnosis of appendicitis by this criteria had a sensitivity of 86.7%, a specificity of 89.7%, a positive predictive value of 94.5%, a negative predictive value of 76.5%, and overall accuracy of 87.6%. All 50 patients with pinpoint tenderness noted on the appendix had appendicitis. The surgeon's initial clinical impression had a sensitivity of 83.3%, a specificity of 44.8%, a positive predictive value of 75.8%, a negative predictive value of 56.5%, and overall accuracy of 70.8%. CONCLUSIONS: The efficacy of ultrasonography using the simple criteria was superior to that of the surgeon's initial clinical impression (P<.001). Our ultrasonographic criteria for the diagnosis of appendicitis are simple to use and efficient.

Acute Disease↗

PubMed1994

Asymptomatic primary mucinous cystadenocarcinoma of the appendix with a large abdominal mass: report of a case.

A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen.

Abdominal Neoplasms↗

PubMed1995

Management and prognosis of adenocarcinoma of the appendix.

PURPOSE: Adenocarcinoma of the appendix is a rare neoplasm, and controversies persist regarding management. The purpose of this study was to identify prognostic factors and define management strategies for patients with adenocarcinoma of the appendix. METHODS: A retrospective case series was conducted at three medical school teaching hospitals over a 20-year period from 1972 to 1992. Overall survival was determined by the actuarial life table method. Comparisons of prognostic factors were made using exact nonparametric log-rank tests. RESULTS: Thirteen patients were diagnosed during the study period. Median age was 62 years. There were five males and eight females. The disease was not suspected in any patient preoperatively. Seventy-seven percent of patients had metastatic disease at presentation. Second primary malignancies were found in 15 percent of patients. Thirty-eight percent of female patients had synchronous ovarian lesions. Median survival was 22 months, with an estimated five-year survival of 43 percent (95 percent confidence interval, 22-84 percent). Patients with colonic histology had significantly worse survival than patients with mucinous histology (P = 0.0093). Patients with carcinomatosis had a significantly worse survival than noncarcinomatosis patients (P = 0.0078). Patients who underwent right hemicolectomy had a better prognosis for survival than appendectomy patients, but the difference was not statistically significant. CONCLUSIONS: Carcinoma of the appendix is very difficult to diagnose preoperatively, and most patients are not identified until disease is advanced. Good prognostic factors include mucinous histology and the absence of carcinomatosis. Right hemicolectomy appears to be a reasonable option, although its superiority to appendectomy alone has not been definitively proven. High frequency of ovarian metastases in women suggests a role for bilateral oophorectomy. In addition, a complete work-up of the patient for a synchronous malignancy, especially in the gastrointestinal tract, should be considered.

Adenocarcinoma↗

PubMed1990

Granular cell tumour of the appendix in a patient irradiated for a rectal carcinoma.

We report on a 47-year-old man with a granular cell tumour of the appendix, discovered incidentally during surgery for a rectal adenocarcinoma that had been irradiated preoperatively. A detailed immunocytochemical analysis revealed positivity for S-100 and neuron-specific enolase (NSE). Electron microscopically, the cytoplasm of the tumour cells contained numerous pleomorphic lysosomes. In the appendix tissue adjacent to the tumour a neuroma and the histological features of radiation injury were present. Our findings suggest that this granular cell tumour may have originated from a pre-existing appendix neuroma which underwent granular degeneration, possibly as a result of radiation.

Appendiceal Neoplasms↗

PubMed1984

Metastatic carcinoid tumor of the appendix. Report of a case and review of the literature.

A case of regional metastatic carcinoid of the appendix is presented and the literature reviewed for indications for right colectomy. Five cases of lymph-node metastasis from primary appendiceal carcinoids less than 2 cm in diameter have been reported. There is no reported case of systemic metastasis occurring after appendectomy for a carcinoid with a diameter of less than 2 cm. Perineural involvement, lymphatic invasion, mesoappendiceal invasion, histologic appearance, and location of the tumor in the appendix seem to be unreliable predictors of clinically significant regional node involvement. It is concluded that a right colectomy is indicated only in patients with carcinoid tumors of the appendix 2 cm or more in diameter, or with residual tumor at the margin of resection.

Adult↗

PubMed2002

Retrospective evaluation of carcinoid tumors of the appendix in children.

Carcinoids of the appendix are rare in children and are usually diagnosed incidentally on histologic investigation following appendectomy for appendicitis. To investigate the significance of the diagnosis of appendiceal carcinoid in children, we conducted a retrospective study of the treatment and follow-up of 36 children with histologically confirmed carcinoid tumors of the appendix. Between 1970 and 2000 a total of 36 patients (25 girls, 11 boys) were diagnosed with appendiceal carcinoid. The median age of the patients at diagnosis was 12.3 years (range 6-16 years). The indication for appendectomy was acute lower right quadrant pain in 27 cases and chronic right lower quadrant pain in 9 patients. In 27 specimens the tumor was localized at the apex, in 7 at the midportion, and in 2 at the base of the appendix. The median tumor diameter was 6 mm (range 3-17 mm). Concomitant severe appendicitis was diagnosed in 14 patients 2 with a perforated appendicitis. In only one tumor were mucin-producing cells detectable. After a median follow-up of 10 years (range 2 months to 30 years) all patients were tumor-free. None of the patients had a synchronous or metachronous noncarcinoid malignant tumor. Appendiceal carcinoids are usually asymptomatic, and the indication for surgical intervention is acute or chronic abdominal pains in the right lower quadrant. For most patients the prognosis is excellent after appendectomy. As in adults, appendectomy is the appropriate treatment.

Adolescent↗

PubMed2003

Mucous cystadenoma of the appendix: is it safe to remove it by a laparoscopic approach?

Mucinous cystadenoma is an uncommon neoplasm of the appendix usually discovered intraoperatively. Its clinical significance lies in the possible rupture and consequent spillage of mucin into the peritoneal cavity, leading to pseudomyxoma peritonei. Even if laparoscopy has been successfully used to perform appendectomy, some concerns exist regarding its use in dealing with mucinous secreting lesions because of possible spillage of mucin during surgery. We report a case of mucous cystadenoma of the appendix, which was successfully removed using a laparoscopic approach. At a 12-month follow-up assessment, the patient was free of disease. We believe that the laparoscopic approach is safe if surgery can be performed without grasping the lesion, and if the specimen is removed through the abdominal wall using a bag. Conversion to laparotomy should be considered if the lesion must be traumatically grasped, or if the tumor clearly extends beyond the appendix.

Appendiceal Neoplasms↗

PubMed2006

Appendix adenocarcinoma associated with ulcerative colitis: a case report and literature review.

Ulcerative colitis (UC) represents a risk factor for colorectal cancer, but the association between UC and appendix cancer is uncommon. A 60-year-old woman with a 5-year history of UC initially received medical treatment with mesalazine and prednisone with no satisfactory response; therefore surgery was indicated. The procedure was a total intersphincteric proctocolectomy with ileostomy. Histopathological analysis indicated adenocarcinoma from the cecal appendix, and chronic-active ulcerative colitis of the colon. In conclusion, surgeons and pathologists should examine every surgical specimen from patients with UC because of the possibility, although remote, of a neoplasic pathology. The appendix adenocarcinoma and ulcerative colitis may or may not be associated, same as colon cancer in patients with UC.

Adenocarcinoma↗

PubMed1990

Carcinoid tumor of the appendix in the first two decades of life.

Carcinoid tumor of the appendix is the most common neoplasm of the gastrointestinal tract in childhood and adolescence. Sufficient long-term follow-up data after surgical treatment are not currently available for patients diagnosed during the first two decades of life. From 1936 to 1988, 23 patients were observed at this institution with histologically confirmed carcinoid tumors involving the vermiform appendix. In contrast to the adult experience, in which the tumor is most commonly encountered as the result of an incidental appendectomy, 18 of these patients presented with signs and symptoms of an acute abdomen directing the surgeon to the appendix. In the other five cases, surgery was performed for other reasons. Median age at presentation was 13.0 years (range, 6 to 20 years). Fourteen patients were female, nine were male. Simple appendectomy was the initial procedure for all patients. Tumor size ranged from "microscopic" to 2.5 cm in largest dimension. Three patients subsequently underwent right hemicolectomy, and one patient had removal of a residual appendiceal stump, but no residual or metastatic tumor tissue was found in any of the resected specimens. Nineteen patients underwent simple appendectomy alone. Eighteen available specimens were reviewed at the time of this study for confirmation of histology and degree of invasion. The tumor invaded to the serosa in nine of 23 (39%). The mesoappendix or periappendiceal fat was involved in seven of 23 (30%). Vessel invasion was not noted in any specimen. Our median follow-up time was very long, being 26 years (range, 9 months to 51 years). No patient has had evidence of recurrent or metastatic disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed2004

Synchronous extraperitoneal and intraperitoneal dissemination of appendix cancer.

BACKGROUND: The aim of this study was to report the role of combined treatments, including cytoreductive surgery and perioperative regional chemotherapy, in patients with synchronous systemic and intraperitoneal dissemination of appendix cancer. METHODS: Patients with synchronous systemic and intraperitoneal dissemination of appendix cancer were treated with cytoreductive surgery and perioperative regional chemotherapy. Variables statistically analyzed with survival as an end point included demographic characteristics, prior surgical score (PSS), tumour marker levels, peritoneal cancer index (PCI), and completeness of cytoreduction (CC). RESULTS: Mean follow up was 42.6 months, median survival time (MST) for 15 patients was 28 months and 5-year survival rate was 29.4%. Female patients had a longer MST than male patients (p=0.0199). Survival was better in patients with PSS 0 and 1 (p=0.0277). Patients with elevated CEA and CA 19-9 levels had a shorter MST (p=0.0083 and p=0.0193, respectively). PCI and CC comparisons did not show significant differences. Morbidity (n=2) and mortality (n=2) rates were 13.3% respectively. CONCLUSION: Acceptable morbidity and mortality and a 29.4% 5-year survival rate allows cytoreductive surgery and regional chemotherapy to be considered as a treatment option for selected patients with synchronous systemic and intraperitoneal dissemination of appendix cancer.

Adenocarcinoma, Mucinous↗

PubMed2005

Immunohistochemical expressions of cytokeratins, mucin core proteins, p53, and neuroendocrine cell markers in epithelial neoplasm of appendix.

Epithelial neoplasms of appendix are infrequent, and their pathological features are not fully characterized. We collected 33 cases of appendiceal tumors and examined immunohistochemically the expression of cytokeratins (CK, CK7, and CK20), mucin core protein (MUC1, MUC2, MUC5AC, and MUC6), E-cadherin, chromogranin A, and p53 protein. Gene analysis of TP53 was also conducted on exons 5 to 8. Clinically, mucinous tumors were predominant in females. Immunohistochemically, all the tumors expressed CK20, whereas CK7 was positive in one third of the cases. Similarly, MUC2 was expressed in all the tumors, whereas MUC1 and MUC5AC were detected in about a half of the cases. Although chromogranin A-positive cells are generally sparse in normal appendix, they were more common in mucinous tumors than in nonmucinous tumors. Contrary to the previous data reported (Mod Pathol 2002;15:599-605), mucinous carcinoma exhibited a higher frequency of p53-positive cells (mean 29%) compared with mucinous adenoma (2.8%) (P < .001), whereas nonmucinous tumors showed high levels of p53-positive cells to similar extent (51%-67%) in both adenoma and carcinoma. The high expression of p53 protein coincided with the presence of mutations in multiple sites of TP53 gene in mucinous tumors. This is the first report that characterized the immunophenotypic profile of appendiceal epithelial neoplasms with an emphasis of a higher frequency of p53 positivity in mucinous carcinoma cases compared with mucinous adenoma in the appendix.

Aged↗

PubMed2005

Chronic abdominal pain secondary to a mucous cystadenoma of the appendix in a 10-year-old boy.

Mucocele of the appendix is a thin-walled dilated appendix filled with mucus. It occurs secondary to chronic obstruction of the appendiceal lumen because of a range of pathologies. Cystadenomas in children are exceedingly rare and most frequently of ovarian origin. A mucous cystadenoma of the appendix in a 10-year-old boy with chronic abdominal pain is presented.

Abdominal Pain↗

PubMed1997

Mucinous tumors of the vermiform appendix and ovary, and pseudomyxoma peritonei: histogenetic implications of cytokeratin 7 expression.

Cytokeratin 7 (CK-7) has been shown to be uncommonly expressed in colonic epithelial tumors, as opposed to ovarian epithelial tumors, which are always CK-7 positive. The authors investigated the expression of CK-7 in 17 appendiceal cystadenomas and carcinomas, 20 mucinous borderline tumors of the ovary, 10 cases of simultaneous mucinous tumors of the appendix and ovary, three so-called high-stage mucinous borderline tumors of the ovary, and three cases of pseudomyxoma peritonei (PP) of unknown origin. Nine appendiceal cystadenomas were CK-7 negative; two of these were associated with PP, and the peritoneal lesions were negative as well. Three cystadenomas were CK-7 positive. Three appendiceal carcinomas were CK-7 negative, and in one case the metastases were also negative. Two carcinomas were CK-7 positive. All 20 ovarian borderline tumors were CK-7 positive. Six cases of simultaneous mucinous tumors of the ovary and appendix were CK-7 negative, as were their peritoneal mucinous deposits. Four cases showed a positive reaction in both appendiceal and ovarian sites. Two of three so-called high-stage ovarian borderline tumors were CK-7 negative. All three cases of PP of unknown origin were CK-7 negative. In conclusion, appendiceal cystadenomas are often CK-7 negative, whereas ovarian mucinous borderline tumors are always CK-7 positive. The concordant staining pattern for CK-7 of simultaneous mucinous tumors involving the appendix and ovary (60% of which were CK-7 negative) supports an appendiceal origin for these tumors. Our results also support an appendiceal (or colonic) source for any CK-7-negative mucinous tumor involving the ovary or the peritoneum. Furthermore, our findings are in agreement with the assumption that mucinous borderline-like tumors in the ovary associated with PP are not ovarian in origin but are often, if not always, metastatic from an appendiceal (or other) mucinous tumor.

Adult↗

PubMed1999

Müllerian-type epithelial tumor arising within a torsed appendix testis.

Because it is a remnant of the müllerian duct system, the appendix testis contains müllerian epithelium that theoretically may produce epithelial tumors similar to those that occur in the female genital tract. Few reports of tumors of müllerian origin arising in the testis exist, and rarely are neoplasms arising from the appendix testis identified. We present a case of a serous cystic neoplasm of low malignant potential derived from müllerian-type epithelium that was located in the torsed appendix testis of a young, otherwise healthy, boy.

Adolescent↗

PubMed1999

Carcinoid tumors of the appendix detected at laparoscopy for gynecologic indications.

STUDY OBJECTIVE: To evaluate the significance of the abnormal-appearing appendix during gynecologic laparoscopy. DESIGN: Retrospective study (Canadian Task Force classification II-2). SETTING: University-affiliated hospital. PATIENTS: One hundred sixty-six women. INTERVENTIONS: Laparoscopic appendectomy. MEASUREMENTS AND MAIN RESULTS: Five of 166 appendixes removed for abnormal appearance contained a carcinoid tumor. At least one patient was a candidate for additional resection. CONCLUSION: It is important for gynecologists to be aware of the possibility of a carcinoid tumor of the appendix, particularly if an abnormality is seen at the time of surgery. (J Am Assoc Gynecol Laparosc 6(3):303-306, 1999)

Adolescent↗

PubMed2003

Sonographic diagnosis of a carcinoid tumour of the appendix in a 14-year-old boy.

Carcinoid tumours of the appendix are rare tumours of the bowel which occasionally are found histologically in resected appendices. There are no publications on the sonographic diagnosis of carcinoid tumours of the appendix in children. We report on the sonographic examination of a carcinoid tumour in a 14-year-old boy. Sonography showed a hypoechoic tumour located at the apex of the appendix with eccentric growth. Histology revealed a carcinoid tumour with invasion of the regional lymphatic vessels.

Adolescent↗

PubMed2003

Intramucosal adenocarcinoma of the appendix: how to find and how to treat.

A colonoscopic examination of a 58-year-old man revealed a small elevated lesion inside the orifice of the appendix. Using a polypectomy snare, a nodular polypoid lesion with a diameter of ca. 20 mm was removed from the lumen of the appendix. Histopathology showed that it was a well-differentiated adenocarcinoma. This is the first report of an intramucosal adenocarcinoma of the appendix diagnosed preoperatively; laparoscopy-assisted colectomy with a D2 lymph-node dissection was carried out. Endoscopists should consider an appendiceal tumor when an erosion, elevation, or deformity is seen in the head of the cecum.

Adenocarcinoma↗