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In a patient with a goblet cell carcinoid tumor of the appendix, light and electron microscopical studies demonstrated mucinous material and enterochromaffin granules within the same cell. Transitions between cells containing primarily mucin and cells containing numerous argentaffin granules were observed. Fluorescence studies demonstrated that the tumor cells contain biogenic amines.
The authors evaluate the incidence of carcinoid tumours out of a total of 2478 appendectomies performed between January 1984 and December 1991 at Treviglio Hospital. Histological tests, routinely performed on all appendixes removed, have revealed an incidence of 0.56% of this disease. Lesions are clinically silent in all cases. In fact, the finding of a carcinoid tumour was coincidental in 12 patients undergoing appendectomy for symptoms of appendicitis, and in two cases in which appendectomy was initially performed during the course of hysterectomy. Eleven cases were histologically of the classical type, including one with a "balloon cell" variant. Lastly, three cases were tubular type adenocarcinoids. In all cases treatment took the form of simple appendectomy. Follow-up studies are still in progress which have enabled the recidivation of neoplasia to be excluded in all patients, even 11 years after treatment.
Carcinoid tumors are infrequent but not exceptional neoplasias. The gastroenteric tract is affected in 80% of cases and almost half of these involve the appendix where they almost always represent an occasional finding after appendicectomy due to acute or subacute appendicitis. Although they have a low malignancy potential in this site, with a reduced index of metastasization and scant capacity to determine clinical symptoms, they are of considerable clinical importance in view of the prognostic and therapeutic type problems that their diagnosis entails. The authors report the case of a female 14-years-old patient, operated for acute appendicitis, and the finding of a yellowish hard tumefaction with a diameter of around 2 cm near the appendicular cone which histological tests showed was a relatively benign classic carcinoid.
Surgical repair of a damaged portion of the ureter cannot always be resolved by mere ureterolysis or resection of the ureter and its "end to end" anastomosis, but it is not always resolved by complete replacement of the ureter by an ileal loop. The presented case-record describes the partial replacement of the abdominal portion of the ureter (9 cm) by an excluded appendix in a 59-year-old patient with a solitary right kidney, suffering from morbus Ormond.
Two cases of simultaneous typhoid perforation of terminal ileum and appendix are reported from Harare Central Hospital. These findings have not been reported before. Perforations were associated with schistosomiasis and HIV/AIDS. Definitive diagnosis was made only after laparotomy, serology and histopathology. With early diagnosis, effective resuscitation and timely intervention, this life-threatening condition is not necessarily fatal. Septic shock is however, an ominous sign of poor prognosis. In the tropics, bradycardia, leukopaenia and perforation in a febrile patient with right iliac fossa tenderness should arouse suspicion. Perforations may occur in patients with underlying diseases.
The relationship of mast cells, nerves and fibrosis was studied in 50 cases of Appendix using simple histochemical technique. In the mucosa, the mast cell number was greater in the early stages of fibrosis. Both in the mucosa and submucosa mast cells were found closely associated with neural tissue. As the fibrosis increased this association between mast cells and neural tissue was retained only in the submucosa.
Based on the concept on gastroenteropancreatic system, endocrinocytes of which are diffusely scattered throughout the digestive tract epithelium and are found in pancreatic islets, an analysis of endocrine apparatus of epithelium in human appendicular mucosa was performed at different stages of ontogenesis. The response of appendicular endocrinocytes to clinical pathology of both this organ and the entire organism was studied. On the base of the analysis of the appendix function from morphological view, the authors proposed a hypothesis postulating it to be an organ equal to an actively functioning endocrine gland and its unique role on early stages of embryogenesis.
The Authors underline the most important pathological, clinical and therapeutic aspects of appendiceal adenocarcinoid. Appendiceal adenocarcinoid is quite a rare tumor, presently considered as a single entity; it differs from typical carcinoid of the appendix because of its well definite histology, its aggressive behaviour and its poorer prognosis. There are no precise prognostic and therapeutic criteria to direct the operative choice between appendectomy and hemicolectomy. In particular the tumor diameter is of no use since the tumor often present diffuse rather than nodular growth. According to most Authors appendectomy is not sufficient in the following cases: liver lymph-node or retroperitoneal metastases; cecal meso-appendiceal or peritoneal spreading; histological poorly differentiated tumors, with nuclear atypia and high mitotic count. Some Authors performed hemicolectomy and bilateral oophorectomy in all case with peritoneal involvement since the ovaries are a frequent site of metastases.
The aim of the study is to reveal the three-dimensional distribution and ultrastructure of the peripheral absorbing lymphatic vessels of the vermiform appendix, since the gut-associated lymphoid tissue is necessary to the immune responses to the enteric antigens. Corrosion casts showed the beginning of the lymphatic vascularization at the tunica mucosa, which lacks intestinal villi, through a tight, delicate lymphatic network. This network drains the lymph by peculiar straight vessels, distributed in the mucosal beams that separate the adjacent follicle domes, in the fine network of the upper portion of the lymphatic basket, surrounding the lateral walls of the basal and medium portions of each lymphoid follicle. This network, which is made of large caliber vessels that are not dilated like sinuses, continues through small vessels into the large dome-like vessels of the submucosa, which in turn by way of the lymphatic vessels of the muscular tunica, drain into the subserous precollector valved lymphatic vessels that flow into the pre-lymph node collectors. We underlined that the particular fluidity of Neoprene latex and the direct injection method, when compared with other substances and injection methods, provided us with exceptionally clear and precise three-dimensional plastic images of the absorbing lymphatic vessels. Moreover, these images extraordinarily illustrated the preservation of the absorbing lymphatic spatial relationships with blood vessels. Ultrastructural features and three-dimensional models of ultrathin serial sections of the absorbing peripheral lymphatic vessels showed a continuous endothelial wall lacking basal lamina, as well as open junctions between adjacent cells. Moreover, we observed the presence of numerous lymphocytes, together with intense transendothelial migratory activity that occurs through intraendothelial channel formations, dynamic entities, at absorbing lymphatic vessels of the peri-interfollicular lymphoid tissue. Also, we saw that the germinal center, as well as the lymphoid follicle dome, lacked lymphatic absorbing vessels. In addition, many postcapillary high endothelial venules (HEV) were observed with lymphocyte migration into the extravasal compartment. Furthermore, we maintain that the absorbing peripheral lymphatic vessels (ALPA) of the tunica mucosa play an important role in liquid drainage. For the peri-interfollicular vessels, we hypothesize a potential migratory and a reserve capacity for lymphocytes, as well as a conduction activity for the muscular tunica and submucosa vessels.
Malignant lymphoma comprises 1-4% of the malignant neoplasm of the gastrointestinal tract. Appendiceal lymphomas are extremely rare, reported in 0.015 percent of all gastrointestinal lymphomas. This is a report of a case of localized malignant lymphoma of the appendix associated with the histological features of acute inflammation that presented clinically as acute appendicitis. A three years follow-up after appendectomy alone did not show any evidence of recurrent disease. This case report emphasizes the importance of routine histology examination of the appendectomy specimen.
Sixty-six young patients (average age, 17.2 years) underwent intestinal operations for Crohn's disease during a 14-year period at the UCLA Hospital. Nine had undergone previous appendectomy for suspected appendicitis, and in seven subsequent enteric fistulae and/or obstruction involving the cecum developed. None of the appendices were acutely inflamed. During the same period, a total of 125 children with Crohn's disease underwent medical or surgical care, and in none did acute appendicitis develop. Of the 66 patients under 22 years old who required intestinal resection, 60 had removal of the cecum. In a child with ileal Crohn's disease, rarely should a normal appendix be removed because of the high likelihood of complications and the low incidence of subsequent appendicitis.
The cellular features of adeno-endocrine-cell carcinoma of appendiceal origin are presented. The pleural fluid contained metastatic predominantly atypical cells in linear cluster accompanied by numerous mesothelial cells. The cells had small round nuclei, with a slight tendency to molding; nucleoli were absent. The cytologic findings in Papanicolaou-stained smears of the pleural fluid suggested a metastatic small-cell carcinoma of the lung. Subsequently, adeno-endocrine-cell carcinoma of the appendix was demonstrated at autopsy. Reports of such occurrences are few; no study, to the best of our knowledge, has previously documented the cytologic diagnosis in pleural fluid.
Carcinoid tumors of the appendix in 30 children younger than 15 years showed no recurrence with up to 24 years' followup, regardless of size, depth of invasion, or presence of perineural involvement. All were treated by appendectomy. Twenty-three of the tumors were in girls, confirming the female preponderance reported in other series.
Adenocarcinoid is a form of appendiceal carcinoid possessing features of both carcinoid and adenocarcinoma. There are two histologic types. Thirty patients had the goblet cell type, characterized by nests of large mucin-distended cells. Nine patients had the tubular type, characterized by small glandular structures lined by uniform cells. Despite abundant mucin and a goblet cell or acinar-like arrangement, a closer relationship to carcinoid than to adenocarcinoma is suggested by a concentration of tumor elements below the crypts of Lieberkuhn, a lack of evidence of neoplastic transformation of the appendiceal mucosa, and the demonstration of argentaffin or argyrophil granules in 88% of the lesions. Six tumors, all of the goblet cell type, metastasized and resulted in the death of the patients. One of the tumours that metastasized had a prominent tubular component. Most adenocarcinoids can be adequately treated by appendectomy, but hemicolectomy is recommended for those tumors showing atypical foci, a high mitotic count, or spread beyond the appendix.
Intraperitoneal chemotherapy with mitomycin C and 5-fluorouracil has been used to rescue patients from peritoneal carcinomatosis after perforated cystadenocarcinoma of the large bowel or appendix. A staging celiotomy was used to asses the results of therapy. In nine patients tumor was recovered from the abdominal cavity and was subjected to careful histopathologic examination. The posttreatment appearance of the tumor was compared with that before treatment. Also, tumor deposits harvested from these same patients, but from anatomic sites not directly exposed to chemotherapy were examined. The most striking findings observed in treated patients were as follows: (1) the marked reduction in the number of foci of atypical neoplastic epithelium lining the mucin globules, and (2) atrophy and degeneration of the atypical neoplastic epithelium. All treated patients showed these effects but they were not in all sampled tumor specimens, suggesting nonuniform drug distribution in the abdominal cavity and limited penetration of chemotherapy into tumor. The authors conclude that intraperitoneal chemotherapy produces marked histologic changes in mucinous tumors when there is direct contact between tumor and intracavitary drugs.
BACKGROUND: Mucinous tumors of the appendix and ovary are known to occur together in association with pseudomyxoma peritonei. It has been postulated that this association may be attributable to the development of independent tumors or to metastasis from one site to another. METHODS AND RESULTS: This article reports two patients with concomitant mucinous ovarian and appendiceal tumors in the absence of pseudomyxoma peritonei. CONCLUSIONS: The evidence suggests that these tumors are independent primary neoplasms that develop as a result of neoplastic field change that affects colonic-type epithelium.
The right bronchus of the short-tailed shrew, Blarina brevicauda, terminates in a nonrespiratory pulmonary appendix (PA) containing two bronchial extensions. The experimentally demonstrated ability of these structures to collect and peristaltically expel aspirated material was initially assumed to be a sufficient reason for their developmental persistence, but as bronchus associated lymphoid tissue (BALT) became a subject of immunologic interest in other species, a possible immunologic role for the concentrations of BALT observed in the shrew PA were investigated. As the BALT of the PA contained many well-differentiated plasma cells and numerous particle-containing macrophages, 6-mu paraffin sections were treated with an immunoperoxidase avidin-biotin preparation that chromogenically identified alpha chains of IgA in many of the PA plasma cells and their associated luminal secretions. Also, vascular injections revealed that the PA had a complex relationship with anastomotic sinusoids connecting the bronchial and pulmonary circulation systems, and scanning electron microscopy showed that the luminal epithelial surfaces of the PA were virtually identical to the scattered BALT aggregates in the bronchi of other animals. It thus appeared that these unique structures in the shrew are morphologically and topographically suited to receive aspirated antigens that induce secretory IgA production, while possibly providing other humoral and cellular immunologic products to the general circulation.
BACKGROUND: Appendiceal carcinoid tumours are found in 0.3-0.9 per cent of patients undergoing appendicectomy. Controversy exists over the management following appendicectomy, especially with regard to the role of right hemicolectomy in patients with tumours smaller than 2 cm in diameter. METHODS AND RESULTS: The literature pertaining to the behaviour of appendiceal carcinoids was reviewed in order to formulate indications for right hemicolectomy. Metastatic disease from appendiceal carcinoids is a rare occurrence, but is more common when lesions are larger than 2 cm in diameter. The risk-benefit balance of right hemicolectomy needs to be better defined, and an improved understanding of tumour cell biology may aid prognostic accuracy and decision-making. CONCLUSION: There is limited evidence on which to base clear indications for right hemicolectomy in patients with a diagnosis of appendiceal carcinoid. Acceptable indications are carcinoids larger than 2 cm in size, any high-grade malignant carcinoid (including those with a high mitotic index), mesoappendiceal invasion, lesions at the base of the appendix with tumour-positive margins, and goblet cell adenocarcinoid tumours.