Primary renal carcinoid tumor with multiple metastases

Primary Carcinoid Tumor of the Renal Pelvis Arising From Intestinal Metaplasia: An Unusual Histogenetic Pathway?

OBJECTIVES

Primary carcinoid tumor of the renal pelvis is a rare neoplasm with few cases reported in the literature. Here we present the clinical and histopathologic findings of a primary carcinoid tumor arising in the left renal pelvis of a horseshoe kidney in a 61-year-old female patient.

MATERIALS AND METHODS

Pathologic features were evaluated with standard hematoxylin and eosin sections and immunohistochemical studies. A literature review was performed to place our case in context to previous reports.

RESULTS

The tumor was associated with intestinal metaplasia with high-grade dysplasia and neuroendocrine hyperplasia. Molecular testing for microsatellite instability and loss of heterozygosity were negative.

CONCLUSIONS

This report portrays a unique presentation of carcinoid tumor arising from intestinal metaplasia of the pelvic urothelium, and supports its histogenesis from urothelial intestinal metaplasia and neuroendocrine hyperplasia.

Primary renal carcinoid tumor: A radiologic review

Carcinoid tumor is the classic famous anonym of neuroendocrine neoplasms. Primary renal carcinoid tumors are extremely rare, first described by Resnick and colleagues in 1966, with fewer than a total of 100 cases reported in the literature. Thus, given the paucity of cases, the clinical and histological behavior is not well understood, impairing the ability to predict prognosis. Computed tomography and (occasionally) octreotide studies are used in the diagnosis and followup of these rare entites. A review of 85 cases in the literature shows that no distinctive imaging features differentiate them from other primary renal masses. The lesions tend to demonstrate a hypodense appearance and do not usually enhance in the arterial phases, but can occasionally calcify. Octreotide scans do not seem to help in the diagnosis; however, they are more commonly used in the postoperative followup. In addition, we report a new case of primary renal carcinoid in a horseshoe kidney.

Renal carcinoid tumor with liver metastasis followed up postoperatively for 9 years

Background

We describe a case of renal carcinoid tumor with liver metastasis followed up postoperatively for 9 years.

Case presentation

A 33-year-old man presented with left flank dull ache. On the abdominal computed tomography, a solid renal mass in the upper portion of the left kidney was detected. The patient had no other abnormal findings, such as suspected distant metastasis or lymph node metastasis. Radical nephrectomy was performed on 14/9/2005. Histological examination and immunohistochemical staining confirm primary renal carcinoid tumor. 9 years after radical nephrectomy, computed tomography of the abdomen demonstrated a 2 cm × 1.8 cm cyst mass in the right liver. Similar pathologic characteristics were found between the renal carcinoid tumor and liver tumor.

Conclusions

We present a primary renal carcinoid tumor with liver metastasis 9 years after radical nephrectomy. With literature review, renal carcinoid tumors exhibit heterogenous behavior.

Neuroendocrine tumors of the kidney: a single institution experience

BACKGROUND

Renal NETs, comprised of carcinoid tumors and small cell carcinomas, are a rare group of neoplasms. The rarity of these tumors pose a diagnostic and therapeutic challenge. Our purpose was to characterize the cases treated at a tertiary cancer center and to evaluate patient outcomes with the available treatment modalities.

PATIENTS AND METHODS

This was a retrospective study of patients with renal NETs seen at The University of Texas M.D. Anderson Cancer Center between January 1, 2001, and January 1, 2011. Patient and tumor data were analyzed using descriptive statistical methods.

RESULTS

Three cases of carcinoid tumors and 6 cases of small cell carcinoma were identified. The median age at diagnosis was 53 years for patients with carcinoid and 65 years for patients with small cell carcinoma. The most common presenting symptoms were back pain, flank pain, and hematuria. The morphological appearance of the tumor cells and their immunohistochemical reactivity for neuroendocrine markers and cytokeratin helped establish the diagnosis. Nephrectomy was the mainstay of treatment for carcinoid tumors, yielding good long-term results, even in the presence of metastases. Surgery and chemotherapy were used for small cell carcinoma of the kidney. The median overall survival for patients with small cell carcinoma of the kidney was 17.3 months.

CONCLUSION

Renal carcinoid tumors are indolent and are associated with prolonged survival, and small cell carcinomas of the kidney are aggressive tumors with relatively short overall survival. Although palliative in nature, cytotoxic chemotherapy is the mainstay of therapy and is best given before surgery.

Primary carcinoid tumour of the kidney: a review of the literature

Context. Primary renal carcinoid tumours are rare. Their pathogenesis is unknown and the clinical presentation is similar to other renal tumours thus posing diagnostic dilemmas for clinicians. Objectives. To review the literature for case reports of primary renal carcinoids. Methods. Literature was extensively searched for case reports for primary renal carcinoids. Reports of metastatic carcinoids to the kidneys were excluded. Results. Approximately less than 90 cases of primary carcinoid tumours of the kidney have been reported in the literature. A total of 29 cases of primary renal carcinoids were reviewed. The mean age of presentation was 48 years (range 29–75) with both right kidney (48.3%) and left kidney (44.8%) being equally affected. 28.6% of the cases reviewed were diagnosed as an incidental finding. The mean followup time was 20 months with 73.1% of patients without evidence of disease after surgical treatment (radical or partial nephrectomy). Primary carcinoid tumours of the kidney are often well differentiated tumours. They are often misdiagnosed because of their rarity and similar presentation with other renal tumours. Conclusions. Primary carcinoid tumours of the kidney are rare tumours with an indolent course with frequent metastasis. Metastatic work up and followup is required in their management.

Primary renal carcinoid: treatment and prognosis

Primary carcinoid tumors of the kidney are very rare, malignant tumors consisting of neuroendocrine cells. The pathogenesis of renal carcinoid is unclear because neuroendocrine cells are not normally found in adult renal parenchyma. Electron microscopy, immunohistochemistry, octreotide scan, positron emission tomography along with conventional radiographic imaging techniques are used in diagnosis and follow-up. Presenting symptoms usually include flank pain and haematuria. Early stage disease is treated with surgery only. However, randomized trials are lacking because of the very low number of reported cases. Thus, the role of debulking surgery, chemotherapy, radiotherapy, octreotide and targeted therapy in the management of advanced disease remains an open question. In this article the clinicopathologic features and prognosis of this very rare disease along with treatment outcomes of the reported cases are reviewed. In addition, we report a new case of a metastatic primary renal atypical carcinoid tumor treated with octreotide therapy.