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Adenocarcinoma of the appendix is unusual at any age but occurs mostly in an elderly population. The authors report a unique case presenting in a 10-year-old child and emphasize the importance of subjecting all resected specimens to histological examination.
We report an unusual case of an enterovesical fistula secondary to adenocarcinoma of the appendix.
Two cases of primary Burkitt's lymphoma of the appendix are reported. Both children presented with abdominal pain, and the tumors were discovered during routine appendectomy for suspected "appendicitis." The rarity of the lesion and the prognosis are briefly discussed.
In travel medicine, as in all other disciplines, there are principles that physicians need to know and understand as well as constant and variable details that need not be memorized but must be readily accessible. This appendix provides a brief listing of resources helpful to primary care physicians who see their patients before and after travel.
Mucous cystadenomas are benign epithelial tumours with great mucous content inside. Despite being non-malignant, they acquired great size, compressing and displacing important structures and organs of the zone, with theirs unlucky outcomes. Surgical exeresis is very difficult, being almost impossible its total exeresis, showing great frequency of relapse. We present an appendix mucous cystadenoma case in a 54 years old patient.
The 10 class I tRNA synthetases have an N-terminal nucleotide-binding fold which contains the catalytic center. Insertions into the nucleotide-binding fold provide contacts for acceptor-helix interactions, which stabilize the amino acid acceptor end of the tRNA substrate in the active site. A separate and largely nonconserved C-terminal domain provides contacts with distal parts of the tRNA, including the anticodon. For Escherichia coli methionyl tRNA synthetase, whose structure is known, the C-terminal domain is predominantly alpha-helical and forms a loop which interacts with the anticodon trinucleotide located about 76 A from the amino acid attachment site. Fused to the end of this helical domain is a peptide which curls back into the N-terminal nucleotide-binding fold and region of the active site. We show here that mutations in this peptide appendix disrupt aminoacylation and binding of a 7 base pair microhelix substrate based on the acceptor stem of tRNA(fMet), without affecting interactions with ATP or methionine or with the tRNA(fMet) anticodon. The impairment of acceptor-helix interactions by mutation of the C-terminal peptide can offset favorable anticodon interactions and severely reduce aminoacylation of tRNA(fMet). Thus, in addition to, or as an alternative to, acceptor-helix-binding insertions into the N-terminal nucleotide-binding fold, C-terminal peptide epitopes in some class I enzymes may provide a mechanism for facilitating RNA microhelix interactions with the catalytic site.
The rates of the forward and reverse reactions of triosephosphate isomerase catalyzed by the wild-type and by a sluggish mutant enzyme have been studied in the absence and the presence of several viscosogenic agents. For the mutant enzyme, the kcat for which is some 10(3) times less than that for the wild-type enzyme, the value of kcat/Km with glyceraldehyde phosphate as substrate is almost unaffected by the presence of sucrose or glycerol, even though the concentration of the aldehyde form of the substrate is smaller because of hemiacetal formation. [The nature and relative amounts of the various forms of triose phosphate present in solution (free carbonyl forms, hydrates, dimers, hemiacetal adducts) have been evaluated by 31P NMR and are presented in the Appendix.] The viscosogenic agents cause the substrate to bind more tightly to the enzyme, roughly compensating for the lower substrate concentration. With dihydroxyacetone phosphate as substrate, the values of kcat/Km for the mutant enzyme increase with the addition of viscosogenic agent, consistent with the tighter binding of substrate without (in this case) any concomitant loss due to hemiketal formation. These results for the mutant enzyme (known to be limited in rate by an enolization step in the catalytic mechanism) can be used to interpret the behavior of the wild-type enzyme. Plots of the relative values of kcat/Km for catalysis by the wild-type enzyme (normalized with the corresponding data for the mutant enzyme) against the relative viscosity have slopes close to unity, as predicted by the Stokes-Einstein equation for a cleanly diffusive process. In the presence of polymeric viscosogenic additives such as poly(ethylene glycol), polyacrylamide, or ficoll, no effect on kcat/Km is seen for the wild-type enzyme, consistent with the expectation that molecular diffusion rates are unaffected by the macroviscosity and are only slowed by the presence of smaller agents that raise the microviscosity. These results show that the reaction catalyzed by the wild-type triosephosphate isomerase is limited by the rate at which glyceraldehyde phosphate encounters, or departs from, the active site.
The isomerization of 3-phospho-D-glycerate and 2-phospho-D-glycerate catalyzed by the cofactor-independent phosphoglycerate mutase from wheat germ (the isolation and crystallization of which is described in the Appendix) has been shown to be intramolecular by two methods. Mass-spectrometric analysis of the products from the isomerization of a mixture of 3-phospho-D-[2(-2)H]glycerate and 3-[18O]phospho-D-glycerate shows that there is no exchange of labeled phosphoryl group between carbon skeletons in the mutase-catalyzed reaction. Analysis of the products from the isomerization of a mixture of 3-phospho-D-[2(-2)H]glycerate and 3-[32p]phospho-D-glycerate by a method involving the kinetic discrimination between 2(-2)H and 2(-1)H species using the enolase isotope effect similarly shows that the wheat germ phosphoglycerate mutase mediates an intramolecular transfer of the phosphoryl group.
Immunoflorescence microscopy of sections of the voodoo lily Sauromatum guttatum appendix stained with monoclonal antibodies against alpha-smooth muscle actin and cytoplasmic actin revealed different staining intensity of different parts of the cell. The anti-cytoplasmic-actin recognized antigens present mainly in the cytoplasm, and the anti-alpha-smooth muscle-actin recognized more intensively antigens present in the nuclei. A positive staining of the nucleus was also obtained with FITC-phalloidin confirming the presence of actin in its filamenous form in the nucleus. The presence of a nuclear alpha-smooth muscle-actin-like protein was further confirmed by confocal laser microscopy. On Western blots, the two anti-actins labelled a protein band that comigrated with standard actin at the approximate molecular weight of 43 kDa. Several other proteins interacted with the two antibodies to a different degree. The monoclonal antibodies against beta-tubulin subunit stained only the periphery of the cytoplasm and anti-pan cytoplasmic myosin stained the cytoplasm weakly. On a Western blot, anti-beta-tubulin subunit primarily recognized a protein band at the appropriate molecular weight of 50 kDa. This is the first cytochemical evidence for the presence of alpha-smooth muscle-actin-like protein in the plant nucleus.
The diagnosis of adenocarcinoid (mucinous/goblet cell carcinoid) is usually unexpected by both clinicians and pathologists. We report here the case of a 74-year-old man with gastric lymphoma (B-cell MALToma) diagnosed by endoscopy, who was found on exploratory laparotomy also to have extensive intraabdominal involvement by adenocarcinoid, arising from the ileum and/or appendix. The patient died two years after diagnosis with bladder outlet and small bowel obstruction due to diffuse metastases. In addition to mucin positivity, immunohistochemical stains demonstrated the tumor to be positive for chromogranin, synaptophysin, serotonin, gastrin, and glucagon. Of histogenetic interest, some individual neoplastic cells appeared to be positive for both mucin and chromogranin, and this was confirmed by the electron microscopic finding of microvilli, intracytoplasmic mucin droplets, and neurosecretory granules involving the same neoplastic cells. This also appears to be the first reported case of adenocarcinoid associated with lymphoma and demonstration of histochemical/immunohistochemical and ultrastructural evidence of cellular components with dual mucinous adenocarcinoma and neuroendocrine features, and the second reported case to have prostatic metastases.
A case of large, and multicentric adenomatoid tumors involving the uterus, right ovary and appendix is described. The uterine tumor was exceptionally large, about 15 cm in maximal diameter, and located in the right fundal region of the uterus with a short, thick pedicle as in a subserous pedunculated uterine fibroid.
It is well established that endogenous overproduction of glucocorticoids may cause osteoporosis. However, knowledge about potential recovery of the skeleton after cessation of corticosteroid excess is limited. We describe a 34-year-old female patient and discuss the complex diagnostic workup that led to the rare diagnosis of carcinoid of the appendix as the cause of Cushing's syndrome. The patient experienced multiple spontaneous rip fractures, and at that time, the bone mineral density of the lumbar spine was 4.3 SD below values for age-matched healthy controls. After removal of the tumour, the patient completely recovered. Measurements at the lumbar spine showed an increase in area bone density of 79% equivalent to 4 SD over a subsequent 3-year observation period. This first case of documented bone mass recovery in a patient cured of ectopic ACTH syndrome suggests a potential for excellent reversibility of steroid-induced osteoporosis and should be considered in the management of such patients.
Appendiceal adenocarcinoma is a rare malignancy for which there is no characteristic clinical presentation. We describe five women who presented with signs and symptoms characteristic of advanced ovarian cancer but whose final diagnosis was stage IV appendiceal cancer. Between 1998 and 1999, five women treated for presumed ovarian cancer were identified as having primary appendiceal cancer. Medical records and pathology were retrospectively reviewed. The median age was 47 years (range 36-61 years). All had elevated preoperative CA125 levels with a median value of 171 micro/ml (range 46-383). Four women underwent right hemicolectomy with two requiring radical surgical tumor debulking to render them optimally debulked. Four had postoperative chemotherapy, the most common agent used was 5-flourouracil. Median survival was 6.75 months (range 19 days-11 months). Primary adenocarcinoma of the appendix is rare; therefore, the clinical utility of radical tumor debulking and chemotherapy is not well described. Given the poor survival in our series, all efforts should be considered palliative. Although this disease process is uncommon, it should be entertained by gynecologic oncologists in the differential diagnosis of an intra-abdominal mass and ascites. The ability to make the correct diagnosis and differentiate between an ovarian and appendiceal primary is critical as the treatment modalities vary.
AIMS: Appendicoliths cause acute appendicitis and appendicular perforation. Do appendicoliths cause acute abdominal pain in the absence of acute appendicitis? METHODS: A retrospective observational study was undertaken of histology reports of all appendicectomy specimens from children < 16 years of age between January 1995 and December 2001. Specimens were categorised as perforated or uncomplicated acute appendicitis, non-inflamed, and "incidental" (removed during abdominal surgery for other indications). The presence of an appendicolith was noted. Clinical details were supplemented by selected case note review. Specimens in which the diagnosis of appendicitis or the presence of an appendicolith were not clearly defined (n = 20) were reviewed by an experienced, independent pathologist. RESULTS: 601 consecutive appendicectomy reports were analysed. The mean age of the study population was 9 years (range 1 day - 15.9 years) and there were 357 boys. An appendicolith was identified in 31/118 (26%) cases of perforated appendicitis, 60/352 (17%) cases of uncomplicated appendicitis, 12/59 (20%) cases of non-inflamed appendices, and only 1/72 (1%) cases of incidental appendicectomies. All patients with an appendicolith in the non-inflamed appendix group had presented with acute abdominal pain mimicking acute appendicitis. The frequency of an appendicolith in perforated appendicitis was significantly greater than in uncomplicated acute appendicitis (chi (2) = 4.8, 1 df, p < 0.05). There was no significant difference in the frequency of an appendicolith between non-inflamed appendices and acute appendicitis (either perforated or intact). Appendicoliths were rarely found in incidental appendicectomies, but these patients were younger. The frequency of appendicoliths in non-inflamed appendices was much greater than that expected from published autopsy data. CONCLUSION: Appendicoliths may cause acute abdominal pain that mimics acute appendicitis.
In a 52 year old pyknic patient in whom very violent pain had suddenly occurred in the left lower abdomen, an acute hemorrhagic infarction of an epiploic appendix of the sigmoid colon with adhesion to the anterior abdominal wall was found to be the cause of the symptoms. A hernia, above all a hernia of the semilunar line of Spigelius, an inflammatory process and a granuloma had to be considered in the differential diagnosis.
In a long-term study of 150 unselected patients with carcinoid tumors of the appendix, we found that the neoplasms were usually less than 1.0 cm in largest dimension and discovered as an incidental finding during surgery performed for other reasons. Metastases were observed with none of the 127 appendiceal carcinoids less than 2.0 cm in largest dimension, with 3 of the 14 lesions greater than or equal to 2.0 cm but less than 3.0 cm in greatest dimension, and with 4 of the 9 lesions greater than or equal to 3.0 cm. Paradoxically, the patients with the larger tumors and metastases were younger than those with smaller and clinically benign tumors. The median age of patients with tumors greater than or equal to 2.0 cm was 31 years and that of those with metastases was 29 years, as compared with a median age of 42 years in patients with nonmetastasizing tumors less than 2.0 cm. We conclude that simple appendectomy is adequate treatment for patients with apparently localized tumors less than 2.0 cm in largest dimension. We have not observed any recurrences or metastases among 122 such patients followed for a median time of more than 26 years. Simple appendectomy is probably also appropriate treatment for lesions greater than or equal to 2.0 cm in elderly patients or in those at high operative risk. Right hemicolectomy seems justified only in young patients with tumors greater than or equal to 2.0 cm who have a low risk of operative morbidity or mortality. Vascular involvement and invasion of the mesoappendix are features that may favor a more radical approach.
Electron microscopy of the cells of the thermogenic appendix of Sauromatum guttatum has revealed a fusion event between pocket-like structures of the rough endoplasmic reticulum (rER) and the plasma membrane. As a result of the fusion event, many regions of the plasma membrane have paired unit membranes (four leaflets instead of two). The fusion allows the transfer of osmiophilic material from the rER pockets to the plasma membrane, where the osmiophilic material is confined to bilayer, pocket-like structures. A clear correlation is found between the presence of the osmiophilic compound and sesquiterpenes. Prior to heat production, the rER- and plasma-membrane pockets are electron dense, and sesquiterpenes are detectable only in tissue extracts. On the day of heat production, electron-translucent pockets are subsequently found and the stored sesquiterpenes are released to the atmosphere. Three sesquiterpenes have been identified by gas chromatography-mass spectrometry as alpha-copaene and beta- and alpha-caryophyllene.
Carcinoid tumours of the gastrointestinal tract are most frequently located at the appendix. We report two cases: In the first case, we realized a simple appendicectomy. In the second case, two weeks after the appendicectomy was performed, according to the histological characteristics of the tumoral specimen, the patient underwent a laparoscopic right hemicolectomy with regional lymphadenectomy. In both cases, 5-HIAA (5 HydroxyIndolAceticAcid) is assayed regularly and remains normal.