Primary carcinoid tumor of kidney. Light and electron microscopy, and immunohistochemical study

Clinical and Pathological Features of Primary Renal Well-Differentiated Neuroendocrine Tumor

Primary carcinoid tumor of the kidney is an extremely rare well-differentiated neuroendocrine tumor, which is generally a low-grade malignant cancer with a good prognosis. Carcinoid tumors are rarely found in the urinary system. Here, we report a 34-year-old woman with primary renal well-differentiated neuroendocrine tumor who underwent nephron sparing surgery and no evidence of recurrence or distant metastasis was found during routine follow-up. We searched the case of renal carcinoid with the search phrase "carcinoid [title] and kidney [title]" and "carcinoid [title] and renal [title]" using the PubMed and restricted the search to articles published in English since 2013. The clinical manifestations, age, sex, tumor size, location, gross pathology, light microscopy and immunohistochemistry were analyzed. A total of 28 cases of renal carcinoid were retrieved from PubMed. Higher proportion of positive labeling of CgA, Syn, NSE and CD56 are most valuable in the diagnosis of primary renal well-differentiated neuroendocrine tumor. At present, radical nephrectomy remains the gold standard in the curative-intent therapy for well-differentiated neuroendocrine carcinoma of kidney, in metastatic renal carcinoid, long-term use of octreotide may be an effective adjuvant therapy.

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: 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.

Primary Carcinoid Tumors of the Kidney

PURPOSE

We describe in detail the features of carcinoid tumors of the kidney. We evaluated possible prognostic factors.

MATERIALS AND METHODS

An extensive search was performed in the medical literature regarding primary carcinoid tumors of the kidney. Epidemiological, clinical, diagnostic, histopathological, therapeutic and prognostic data were evaluated. Several potential risk factors were compared with the incidence of metastases and clinical outcome of the patients.

RESULTS

A total of 56 case reports were reviewed. Median patient age was 49 years. Horseshoe kidneys were present in 17.8% of cases. Incidental diagnosis was made in 28.6% of patients. The most common symptom was abdominal or flank pain and neuroendocrine syndromes occurred with only 12.7% of primary renal carcinoid tumors. Of the patients 73.6% presented with tumors larger than 4 cm. Metastases were present in 45.6% of patients at initial diagnosis and almost 60% with tumors greater than 4 cm had metastases.

CONCLUSIONS

Renal carcinoid is the second most prevalent genitourinary carcinoid in each sex, following testicular carcinoids in men and ovarian tumors in women. Significant adverse prognostic factors include age greater than 40 years, tumor size greater than 4 cm, purely solid tumors on the cut surface, mitotic rate higher than 1/10 high power fields, metastasis at initial diagnosis and tumors extending throughout the renal capsule.

Carcinoid tumors of the urinary tract and prostate

CONTEXT

Carcinoid tumors are exceedingly rare in the genitourinary tract and may occur in the kidney, urinary bladder, urethra, or prostate.

OBJECTIVE

To review the clinical and pathologic features of carcinoid tumors occurring in the urinary tract and prostate.

DATA SOURCES

We searched the English language literature using MEDLINE and Ovid.

CONCLUSIONS

Carcinoid tumors of the urinary tract and prostate share similar morphologic features with their counterparts in other organs. The differential diagnosis includes metastatic carcinoid tumor, paraganglioma, and nested variants of urothelial and prostatic carcinomas. Correlation of the clinical presentation and histopathologic features (including the immunohistochemical profile) will ensure accurate diagnosis of these rare tumors.

Primary carcinoid tumor in a polycystic kidney

A case of a primary carcinoid tumor within a polycystic kidney is reported. A 51-year-old woman with autosomal dominant polycystic kidney disease (ADPKD) underwent a bilateral nephrectomy because of an infection in her polycystic kidneys. A tumor (1.5 cm in diameter) was incidentally found close to the hilum of the left kidney. Histologically, the tumor exhibited a predominantly trabecular pattern of cuboidal or columnar cells. Grimelius staining showed numerous silver-stained neurosecretory granules in most of the tumor cells; the tumor cells were also positive for chromogranin, synaptophysin, prostatic acid phosphatase (PAP) and neuron-specific enolase (NSE). The tumor was diagnosed as a primary carcinoid tumor of the kidney. Primary renal carcinoid is a very rare neoplasm, and this is the first report of such a lesion arising in a polycystic kidney.

Primary carcinoid tumor in a horseshoe kidney

A case of primary carcinoid tumor arising within a horseshoe kidney in a 51-year-old woman is reported. The tumor was found incidentally by computed tomography (CT) during a check-up for a suspected gall bladder polyp. Histologic, immunohistochemical and electron microscopic analyses of this tumor revealed features typical of carcinoid tumor. Primary carcinoid tumor of the kidney is extremely rare and only 32 cases were previously reported, including five cases in horseshoe kidneys. None of these five cases in horseshoe kidneys demonstrated any evidence of local or distant metastases and all were alive at the time of reporting without evidence of disease after up to 3 years of follow up. The present case, even with accompanying lymph nodal metastasis, also has had no evidence of local recurrence or distant metastasis for 3 years post operation. Primary carcinoid tumor arising within horseshoe kidneys appear to be more benign than those within non-horseshoe kidneys.

Carcinoid tumor of the kidney. The use of somatostatin receptor scintigraphy in diagnosis and management

Three patients were diagnosed with carcinoid tumors of the kidney. The diagnosis was rendered after biopsy with the assistance of immunohistochemical stains. In all three patients, a pentetreotide scan was helpful in staging. Metastatic disease that was not evident by computed tomography was found in one patient. All three patients are alive with stable or slowly progressive disease at 33, 36, and 40 months. Carcinoid tumors arising from the kidney are rare but must be considered in the differential diagnosis of a renal mass. Immunohistochemical staining is important in the diagnosis of these tumors and the pentetreotide scan contributes to accurate staging.

Renal carcinoid and horseshoe kidney: a frequent association of two rare entities--a case report and review of the literature

We report the case of a primary renal carcinoid tumor associated with a horseshoe malformation in a 43-year-old man who presented with testicular pain. The tumor was centrally located and purely solid and had features ascribed to hindgut neuroendocrine neoplasia. The relative risk of developing a carcinoid tumor in a horseshoe kidney is estimated to be x82.

Primary carcinoid tumour with ossification masquerading as calyx stone in a horseshoe kidney

A case of renal carcinoid tumour arising within a teratoma in a horseshoe kidney in a 23-year-old male is reported. The presenting symptom was abdominal pain, and bone tissue within the tumour was initially misinterpreted as a calyx stone, leading to unsuccessful attempts at extracorporeal shock-wave lithotripsia and percutaneous lithotripsia. This unusual tumour is over-represented in patients with horseshoe kidney and other congenital developmental renal defects.

Endocrine carcinoma of the kidney

A 4-cm mass in the right kidney of a 43-year-old female had an endocrine appearance by light microscopy and electron microscopy confirmed this impression, demonstrating the presence of numerous cytoplasmic granules of endocrine caliber. Unusual features were patchy immunoreactivity for chromogranin, and polarity of the granules within the neoplastic cells. Extrarenal extension and liver metastasis were documented.

Primary carcinoid tumor of the kidney with special reference to its histogenesis

A case of primary carcinoid tumor of the kidney occurring in a 66-year-old woman is reported. The tumor was 10 x 10 x 9 cm in size, solid, yellowish-white in color, and associated with massive hemorrhagic necrosis. Histologically, it was composed of trabecular and anastomosing ribbon-like nests. The tumor cells showed argyrophilicity with the Grimelius stain and cytoplasmic positivity for neuroendocrine markers, (including chromogranin A, neuron-specific enolase, synaptophysin and Leu-7), prostatic acid phosphatase, keratin and vimentin. Numerous cytoplasmic neurosecretory granules were demonstrated ultrastructurally. These histologic and immunohistochemical findings are consistent with the theory that this tumor has a common phenotype with that of carcinoid tumor arising from the hindgut or cloaca.

A primary carcinoid tumor of the kidney: a case report and review of the literature

BACKGROUND

Primary carcinoids are found mostly in the gastrointestinal tract. Primary carcinoid tumor of the kidney is rare; only 28 patients have been reported. Because of the rarity of the lesion, its radiological and clinicopathological features are not well characterized. At the same time, its prognosis and histogenesis is unknown.

METHODS

A 62-year-old patient presented with a carcinoid tumor on the isthmus of the horseshoe kidney. Radiological, clinicopathological, and immunohistochemical tests were performed. The tumor was resected.

RESULTS

Two years later, metastasis were observed in the liver. The metastasis were treated with percutaneous ethanol sclerotherapy (PET).

CONCLUSIONS

To our knowledge, this is the first case of primary renal carcinoid tumor present on the isthmus of the horseshoe kidney and the first case of carcinoid liver metastasis to be treated with PET.

Primary carcinoid of the kidney

A rare case of primary renal carcinoid tumour is presented. The diagnosis was based on immunohistochemically diffuse cytoplasmic positivity for chromogranin A and neuron-specific enolase, in addition to histologic findings. Only 14 previous cases of this tumour have been documented in the literature.

Primary carcinoid of the kidney. Immunohistochemical and ultrastructural studies of five patients

BACKGROUND

Primary carcinoid tumor of the kidney is rare; only 18 patients have been reported. Because of the rarity of the lesion, its prognosis and clinicopathologic features are not well characterized, and its histogenesis is unknown.

METHODS

Clinicopathologic, immunohistochemical, and ultrastructural studies were performed on five patients with primary carcinoid tumor of the kidney.

RESULTS

Age of the patients ranged from 42 to 63 years, with a mean of 53.2 years. Only one patient had a carcinoid syndrome. Three were men, and two were women. In each patient, the tumor was solitary and confined to the kidney. All tumors had histologic features identical to those of carcinoid tumors affecting other sites. The cytoplasmic granules of the tumor cells were reactive with Grimelius stain in all patients. All tumors also were immunoreactive for keratin, neuron-specific enolase, and chromogranin, but only two patients had tumors that reacted for serotonin, pancreatic polypeptide, and vasoactive intestinal polypeptide. Ultrastructural studies showed numerous intracytoplasmic neuroendocrine granules in four tumors. One patient had Robson Stage I cancer, and two each had Stage II and IV cancer. The two patients with Stage IV tumor died of disease at 36 months and 28 months after diagnosis; one patient with Stage II carcinoid is alive without clinical evidence of residual disease 8 years after control of metastases; the other patient with Stage II and the patient with Stage I cancer are alive and well without evidence of disease at 36 months, and 2 months, respectively.

CONCLUSION

Tumor stage at presentation appears to be the most important factor in determining outcome. The number of mitoses and degree of cellular atypia appear to be important pathologic parameters in predicting prognosis, despite the limited number of patients reported in this report.

Primary renal carcinoid tumor

We report a case of primary renal carcinoid tumor. Only 13 prior cases are documented in the literature. The tumor fulfilled both histologic and immunochemical criteria for carcinoid. In addition, we employed new diagnostic modalities (i.e., magnetic resonance imaging and chromogranin-A levels) not used in prior published reports. A review of the literature is presented.

Carcinoid tumor of the kidney with morphologic and immunohistochemical profile of a hindgut endocrine tumor: report of a case

A 54-year-old man underwent a radical nephrectomy for a presumed renal cell carcinoma. The tumor was large, showed areas of cystic degeneration and calcification, and had completely obliterated the normal renal parenchyma. The light microscopic appearance was atypical for renal cell carcinoma, and when electron microscopy revealed innumerable neurosecretory granules a diagnosis of carcinoid tumor was made. The tumor cells were argentaffin- and argyrophil-negative but were chromogranin-, neuron-specific enolase-, and leu-7-positive. When tested with a battery of antibodies against specific polypeptide hormones, the tumor exhibited diffuse pancreatic polypeptide and focal somatostatin immunoreactivity. Our case represents only the 16th case of carcinoid tumor of the kidney to be reported and the first with demonstrated pancreatic polypeptide immunoreactivity. The predominantly trabecular histology, nonreactivity with silver stains, and immunohistochemical profile of this case are common characteristics of hindgut carcinoids, suggesting that, like rectal carcinoids, renal carcinoids are tumors of hindgut endocrine cells.

Primary renal carcinoid--case report

Carcinoid tumour is a rare cause of a renal mass. Only fourteen cases have been reported since it was first described in 1966. This case illustrates most of the commoner features.