A cystic nephroma, also known as

multilocular A locule (plural locules) or loculus (plural loculi) (meaning "little place" in Latin) is a small cavity or compartment within an organ or part of an organism (animal, plant, or fungus). In angiosperms (flowering plants), the term ''locule'' usu ...

cystic nephroma, mixed epithelial stromal tumour (MEST) and renal epithelial stromal tumour (REST), is a type of rare

benign Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous benign tumor, ''benign'' tumor in that a malign ...

kidney tumour Kidney tumours are tumours, or growths, on or in the kidney. These growths can be benign or malignant (kidney cancer). Presentation Kidney tumours may be discovered on medical imaging incidentally (i.e. an incidentaloma), or may be present in pat ...

Symptoms

Cystic nephromas are often asymptomatic. They are typically discovered on

medical imaging Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to rev ...

incidentally (i.e. an

incidentaloma In medical or research imaging, an incidental imaging finding (also called an incidentaloma) is an unanticipated finding which is not related to the original diagnostic inquiry. As with other types of incidental medical findings, they may represen ...

Diagnosis

Cystic nephromas are diagnosed by

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...

or excision. It is important to correctly diagnose them as, radiologically, they may mimic the appearance of a

renal cell carcinoma Renal cell carcinoma (RCC) is a kidney cancer that originates in the lining of the proximal convoluted tubule, a part of the very small tubes in the kidney that transport primary urine. RCC is the most common type of kidney cancer in adults, resp ...

that is cystic.

Pathologic diagnosis

The characteristics of cystic nephromas are: *

Cyst A cyst is a closed sac, having a distinct envelope and cell division, division compared with the nearby Biological tissue, tissue. Hence, it is a cluster of Cell (biology), cells that have grouped together to form a sac (like the manner in which ...

s lined by a simple epithelium with a ''hobnail morphology'', i.e. the nuclei of the cyst lining epithelium bulges into the lumen of the cysts, *

Ovarian The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. T ...

-like stroma that has a: **

Spindle cell Von Economo neurons (VENs), also called spindle neurons, are a specific class of mammalian cortical neurons characterized by a large spindle-shaped soma (or body) gradually tapering into a single apical axon (the ramification that ''transmits ...

morphology, and has a **Basophilic

cytoplasm In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. The ...

. Cystic nephromas have an immunostaining pattern like ovarian stroma; they are positive for: * Estrogen receptor (ER), * Progesterone receptor (PR) and *

CD10 Neprilysin (), also known as membrane metallo-endopeptidase (MME), neutral endopeptidase (NEP), cluster of differentiation 10 (CD10), and common acute lymphoblastic leukemia antigen (CALLA) is an enzyme that in humans is encoded by the ''MME'' ge ...

Differential diagnosis

Renal tumors by relative incidence and prognosis

cystic partially differentiated nephroblastoma A cyst is a closed sac, having a distinct envelope and division compared with the nearby tissue. Hence, it is a cluster of cells that have grouped together to form a sac (like the manner in which water molecules group together to form a bubble); ...

*cystic standard nephroblastoma (cystic

Wilm's tumor Wilms' tumor or Wilms tumor, also known as nephroblastoma, is a cancer of the kidneys that typically occurs in children, rarely in adults.; and occurs most commonly as a renal tumor in child patients. It is named after Max Wilms, the German surge ...

) *cystic

mesoblastic nephroma Congenital mesoblastic nephroma, while rare, is the most common kidney neoplasm diagnosed in the first three months of life and accounts for 3-5% of all childhood renal neoplasms. This neoplasm is generally non-aggressive and amenable to surgical r ...

*cystic

*other

renal cyst A renal cyst is a fluid collection in or on the kidney. There are several types based on the Bosniak classification. The majority are benign, simple cysts that can be monitored and not intervened upon. However, some are cancerous or are suspicio ...

Additional images

Image:Cystic_nephroma_intermed_mag.jpg,

Micrograph A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a mic ...

of a cystic nephroma.

H&E stain Hematoxylin and eosin stain ( or haematoxylin and eosin stain or hematoxylin-eosin stain; often abbreviated as H&E stain or HE stain) is one of the principal tissue stains used in histology. It is the most widely used stain in medical diagnos ...

References

External links

{{Urologic neoplasia Benign renal neoplasms