a 46-year - old female presented with vague gastrointestinal symptoms , chronic right upper quadrant abdominal pain and intolerance to fatty food and diarrhea for the last two years .
she was given the diagnosis of irritable bowel syndrome and had been followed by her internist .
she had undergone an abdominal hysterectomy with bilateral salpingo - oophorectomy for menometrorrhagia and fibroids 15 years ago but was otherwise healthy . during the work - up , an ultrasound ( u / s ) of the abdomen revealed several small stones in the fundus of the gallbladder and a common bile duct of normal diameter .
laparoscopic visualization of the abdominal cavity revealed a small brownish mass at the tip of the appendix resembling a lymph node .
the camera was then moved from the supraumbilical port to the subxyphoid one . using the same instruments , ie , two endo grasps plus a multifire endo gia 30 stapler , the appendix
pathologic examination demonstrated a carcinoid tumor in the tip of the appendix , which measured 0.3  0.2 cm ( figure 1 , 2 ) .
the margins of the specimen were clear , no lymph nodes were seen , and there was no mesoappendix invasion .
. longitudinal section of the appendix tip demonstrating nests of uniform , polygonal cells with round , centrally placed nuclei , characteristic of carcinoid tumors , 200x .
merling , in 1838 , described the gross pathology of carcinoid tumor of the appendix , and in 1907 oberndorfer coined the term  karzinoide .
carcinoid tumors of the midgut arise from the distal duodenum , jejunum , ileum , appendix , and ascending and right transverse colon , with the appendix and terminal ileum being the most common locations .
carcinoids share common histochemical characteristics with other gut cells ; they originate as solid nests of small monotonous neuroendocrine cells with high rare mitoses and occasional acinar or rosette formation .
they have a high amine content in the cytoplasm , are capable of amine precursor uptake , and are able to decarboxylase these products to synthesize amines and/or peptides , such as tachykinins ( substance p , neurokinin a , neuropeptide k ) and others .
godwin reviewed 2,837 cases of carcinoid tumor and found that the majority originate from the gastrointestinal tract ( 85% ) , but they were also found in the lung , ovary , and biliary tracts .
carcinoid tumors showed several differences from other kinds of tumor , including a low age for appendiceal and lung cases and low male / female and black / white ratios in the lung .
godwin 's percentages of concurrent neoplasm and multiple carcinoids were low compared to other series .
five - year relative survival rates ranged from 99% ( appendix ) to 33% ( sigmoid colon ) .
however , survival for colon cases was not as low as expected on the basis of the high rate of metastases .
histologically , there are five generally accepted carcinoid growth patterns , ie , insular ( type a ) , trabecular ( type b ) , glandular ( type c ) , undifferentiated ( type d ) , and mixed type . the mixed tumors with acinar and glandular pattern have the best median survival time ( 4.4 years ) , whereas the undifferentiated has the poorest median survival ( 0.5 year ) . in decreasing order of median survival time in years , the growth patterns ranked as follows : mixed insular plus glandular , 4.4 ; insular , 2.9 ; trabecular , 2.5 ; mixed insular plus trabecular , 2.3 ; three pooled low incidence rate mixed growth patterns , 1.4 ; glandular , 0.9 ; and undifferentiated , 0.5 .
the site of origin and rate of metastases varies , with appendix being the most common site of carcinoid .
carcinoids of the appendix and rectum smaller than 2 cm have a 5-year survival rate of approximately 100% , declining to 40% when the tumor diameter is larger than 2 cm .
however , metastases have been reported from carcinoid of the appendix less than 2 cm in size . while the risk of metastasis of these tumors has been correlated with their size , invasion of
the mesoappendix is predictive of an increased risk of metastasis for carcinoid tumors of the appendix less than 2 cm in size .
the clinical presentation of carcinoid tumors depends on their location with a wide clinical spectrum varying from asymptomatic to the malignant carcinoid syndrome .
they are , in most instances , found incidentally at operation , as in our case .
a third of patients with carcinoid present with years of intermittent abdominal pain often ascribed to other gastrointestinal or biliary disease , or to the irritable bowel syndrome .
malignant carcinoid tumors may present with symptoms of mechanical bowel obstruction due to fibrosis , adhesions and kinking of the intestine .
other constitutional symptoms include weight loss , diarrhea , upper gastrointestinal bleeding , intussusception , and abdominal mass . in patients with carcinoid of the foregut ( atypical carcinoid )
, the urine contains only slightly elevated levels of 5-hydroxyindoleacetic acid ( 5-hiaa ) , but large quantities of 5-hydroxytryptophan ( 5-htp ) and 5-hydroxytrypta - mine ( 5-ht ) , because these tumors are deficient in dopadecarboxylase , which is responsible for the conversion of 5-htp to 5-ht .
in carcinoid of the midgut ( typical carcinoid ) most of the 5-htp is rapidly converted to 5-ht , which is taken up by platelets .
the excess of 5-ht is converted by monoamino oxidase ( mao ) and aldehyde dehydrogenase ( da ) to 5-hiaa , which then is excreted in high concentrations in the urine .
it is interesting to note that serotonin - rich foods , such as bananas , plantains , pineapples , kiwi fruits , wal - nuts , hickory nuts , pecans , avocados , and acetaminophen may artificially elevate 5-hiaa .
numerous techniques can identify the primary site of the tumor . a chest radiograph or computed tomography ( ct ) may show a bronchial or mediastinal tumor double - contrast gastrointestinal studies still best define the primary neoplasm .
appendiceal tumors frequently escape radiological detection until large enough to be discovered by computed tomography ( ct ) .
the hypervascular nature of carcinoid tumors and their metastases allows superior mesenteric arteriography of the small bowel and cecum to be used when the scanning procedures are not revealing .
configuration of the desmoplastic mesenteric masses and lymph node metastases are best seen by ct , whereas hepatic metastases can be demonstrated by ct , ct - angioportography ( ctap ) , ultrasonography ( us ) , magnetic resonance imaging ( mri ) , and octreotide scintigraphy .
percutaneous needle biopsy with radiological guidance may confirm the diagnosis of carcinoid tumors and their metastases .
appendiceal carcinoid tumors are rarely malignant , and lesions smaller than 1.5 cm can be safely resected by appendectomy only .
if the tumor is at the base of the appendix , a cecectomy may prove necessary .
laparoscopic resection of carcinoid tumors from the stomach , gallbladder , proximal and distal rectum have been described .
laparoscopic appendectomy has been compared to open procedures , and the results showed open procedures taking less time , but there were more wound infections than in the laparoscopic procedure .
patients with acute appendicitis recuperated more quickly from the laparoscopic procedure , as evidenced by the time until eating regular diet , period of hospitalization , incidence of nausea and pain medications on postoperative day one .
we report a case of incidental laparoscopic resection of a carcinoid tumor at the tip of the appendix during an elective laparoscopic cholecystectomy . even though the risk of metastasis from carcinoid correlates with the size , ie , greater than 2 cm , there are several cases of metastatic disease from carcinoid tumors smaller than 1 cm in diameter . based on review of the literature ,
we suggest that any suspicious lesion of the appendix found during laparoscopic exploration of the abdominal cavity should be removed .
we believe that the magnification provided by the laparoscope , ie , up to 18 times , and the ability to inspect the abdominal cavity allowed us to identify the lesion and to perform laparoscopic appendectomy while adding minimal morbidity to the procedure .
 carcinoid tumors of the midgut arise from the distal duodenum , jejunum , ileum , appendix , ascending and right transverse colon . 
 the appendix and terminal ileum are the most common location . 
 the majority of carcinoid tumors originate from neuroendocrine cells along the gastrointestinal tract , but they are also found in the lung , ovary , and biliary tracts . 
 we report the first case of elective laparoscopic cholecystectomy in which we found a suspicious lesion at the tip of the appendix and proceeded to perform a laparoscopic appendectomy . 
 the lesion revealed a carcinoid tumor of the appendix . 
CASE REPORT
DISCUSSION
CONCLUSION