To the editor: Contraindicating  the start  of  chronic  dialysis  in  a  patient with  an  advanced  malignant  tumor1

may be very difficult if the patient is in a good general condition and symptomfree. An  example  of  a  situation  where this may occur are  patients with carcinoid  tumors,  an  uncommon  condition with a high survival rate despite its high metastatic  capacity  that  grows  slowly and  has  an  indolent  course  in  many cases.2,3



The case of a 72-year-old male patient  in  whom  evidence  of  chronic renal  failure  for  an  unknown  cause

was  detected  in May  2006  during  a work-up study for isomorphic macrohematuria  episodes  is  reported.  A

cystoscopy  and  several  urine  cytologies  showed  no malignancy. The  patient started hemodialysis two months

later due  to uremic clinical signs. An urological  MRI  performed  a  little later showed right pyelocalycial ectasis with a pelvic filling defect approximately  2.5  cm  in  diameter  suggesting  a urinary  tract  tumor,  as well  as

multiple  hepatic  lesions.  FNA of  the liver  showed  carcinoma  consistent with metastasis from a neuroendocrine  tumor. An  oncological  octreotide scan,  performed  in August  2006,  revealed  scintigraphic  uptake  suggesting lesions with a high density of somatostatin  receptors  in  the  liver. The presence of foci with a high uptake in

the thoracic study suggested the diagnostic  possibility  that  the  primary tumor was of pulmonary or bronchial

origin  (fig.  1),  but  a  subsequently performed  CT scan  of  the  chest  and abdomen  showed  no  obvious  lesions in  mediastinum  or  lungs.  However, the  patient  was  still  asymptomatic, with a good general condition and tolerating  well  hemodialysis  sessions. The  only  remarkable  findings  were resistance  to  erythropoietin  and  a consequent  trend  to  anemia.  Under the  control  of  the  oncology  department,  patient was  treated with  intramuscular  somatostatin  analogs,  but never had a carcinoid syndrome (episodes  of  flushing,  dyspnea,  diarrhea, or  right  valve  disease).  Because  of occasional  recurrence  of  hematuria with  discomfort  in  the  right  lumbar area  and based on  the  suspicion of  a non-endocrine  tumor  because  of  the absence of scintigraphic uptake in the octreotide  scan,  a  control  urological MRI was performed half a year later. MRI  showed  persistent  hepatic  lesions mainly in the right lobe, and an infiltrative lesion in the right pyeloureteral  junction  causing  significant dilation  of  the  collecting  system. There was an additional mass that lobulated  the  cortical  contour  of  the same  kidney,  appeared  to  communicate with  the  renal pelvis  lesion, and had a greater axis of 4.2 cm. Based on these  findings,  the  case  was  re-evaluated  by  the  oncology  and  urology departments, and a right nephrectomy was  performed.  The  postoperative course  was  very  torpid.  Transfusion

of several red cell packs and debridement  of  an  intraabdominal  abscess were  performed,  despite  which  the

patient died a  few days  later. A renal pathological  study  revealed  a  grade 3-4  renal  cell  carcinoma  with  wide

necrotic areas and a predominance of eosinophilic  cells. Lymph  nodes  isolated from renal fat and hilum had no

neoplastic infiltration.



Carcinoid  tumors  are  neoplasms originating from cells of the neuroendocrine  system.  Two  thirds  of  these

tumors are  located  in  the gastrointestinal  tract  (41.8%  in  the small bowel, 27.4%  in  rectum,  and  8.7%  in  stomach).3 Pulmonary and bronchial carcinoid tumors have also occurred. Typical  tumors  have well  differentiated

cells  and  usually  involve  the  hilum, but less common, atypical tumors also occur  in  more  peripheral  locations

and in older patients.2 Tumors may secrete  hormones,  causing  the  classical carcinoid syndrome, but there are also non-secreting  tumors.  Severity  depends on tumor size and the extent of metastases,  particularly  if  they  occur in  the  liver.  In addition  to conventional  imaging  tests,  scintigraphy  is  essential to study the extent of this neoplasm.3



It is known that carcinoid tumors are sometimes  associated  to  other  tumors. Approximately  15%  of  carcinoid  tumors arising in the small bowel are associated  to  non-carcinoid  neoplasms, most  of  them  adenocarcinomas  of  the gastrointestinal tract.4



It is noteworthy how, in the case reported,  the  study  of  a  symptom  such as hematuria led us to diagnose a very

advanced chronic  renal  impairment, a carcinoid  tumor, and  finally, a hypernephroma. It should also be noted that a  metastatizing  tumor,  a  carcinoid tumor  in our  case, may  follow  an  indolent  course.  The  patient  was  in  a good general condition, and his death was  eventually  caused  by  other  reason. The need  for  a  scintigraphic  test such as an oncological octreotide scan is  stressed,  as  the  absence  of  uptake showed  us  that  the  renal  tumor  was not  a  carcinoid.  Moreover,  primary renal carcinoid tumor is extremely infrequent.5



We think that coexistence of a carcinoid  tumor  and  hypernephroma  is  casual,  because  only  another  case  in

which  a  carcinoid  tumor  in  the  cecal appendix and a renal cell carcinoma coexisted in the same patient was found in the literature.6