Desmoplastic small-round-cell tumor

Display of small round blue cells characteristic of desmoplastic small-round-cell tumor.

Cell exhibiting blue oval and round shapes of desmoplastic small-round blue cell tumor

There are few early warning signs that a patient has a DSRCT. Patients are often young and healthy as the tumors grow and spread uninhibited within the abdominal cavity. These are rare tumors and symptoms are often misdiagnosed by physicians. The abdominal masses can grow to enormous size before being noticed by the patient. The tumors can be felt as hard, round masses by palpating the abdomen.

First symptoms of the disease often include abdominal distention, abdominal mass, abdominal or back pain, gastrointestinal obstruction, lack of appetite, ascites, anemia, and cachexia.

Other reported symptoms include unknown lumps, thyroid conditions, hormonal conditions, blood clotting, kidney and urological problems, testicle, breast, uterine, vaginal, and ovarian masses.

There are no known risk factors that have been identified specific to the disease. The tumor appears to arise from the primitive cells of childhood, and is considered a childhood cancer.

Research has indicated that there is a chimeric relationship between DSRCT and Wilms' tumor and Ewing's sarcoma. Together with neuroblastoma and non-Hodgkin's lymphoma, they form the small-cell tumors.

DSRCT is associated with a unique chromosomal translocation t(11;22)(p13:q12)[5] resulting in an EWS/WT1 transcript[6] that is diagnostic of this tumor.[7] This transcript codes for a protein that acts as a transcriptional activator that fails to suppress tumor growth.

The EWS/WT1 translocation product targets ENT4.[8] ENT4 is also known as PMAT.

The entity was first described by pathologists William L. Gerald and Juan Rosai in 1989.[9] Pathology reveals well circumscribed solid tumor nodules within a dense desmoplastic stroma. Often areas of central necrosis are present. Tumor cells have hyperchromatic nuclei with increased nuclear/cytoplasmic ratio.

On immunohistochemistry, these cells have trilinear coexpression including the epithelial marker cytokeratin, the mesenchymal markers desmin and vimentin, and the neuronal marker neuron-specific enolase. Thus, although initially thought to be of mesothelial origin due to sites of presentation, it is now hypothesized to arise from a progenitor cell with multiphenotypic differentiation.

DSRCT is frequently misdiagnosed. Adult patients should always be referred to a sarcoma specialist. This is an aggressive, rare, fast spreading tumor and both pediatric and adult patients should be treated at a sarcoma center.

There is no standard protocol for the disease;[10] however, recent journals and studies have reported that some patients respond to high-dose (P6 Protocol) chemotherapy, maintenance chemotherapy, debulking operation, cytoreductive surgery, and radiation therapy. Other treatment options include: hematopoietic stem cell transplantation, intensity-modulated radiation therapy, radiofrequency ablation, stereotactic body radiation therapy, intraperitoneal hyperthermic chemoperfusion, and clinical trials.

The prognosis for DSRCT remains poor.[11] Prognosis depends upon the stage of the cancer. Because the disease can be misdiagnosed or remain undetected, tumors frequently grow large within the abdomen and metastasize or seed to other parts of the body.

There is no known organ or area of origin. DSRCT can metastasize through lymph nodes or the blood stream. Sites of metastasis include the spleen, diaphragm, liver, large and small intestine, lungs, central nervous system, bones, uterus, bladder, genitals, abdominal cavity, and the brain.

A multi-modality approach of high-dose chemotherapy, aggressive surgical resection,[12] radiation, and stem cell rescue improves survival for some patients. Reports have indicated that patients will initially respond to first line chemotherapy and treatment but that relapse is common.

Some patients in remission or with inoperable tumor seem to benefit from long term low dose chemotherapy, turning DSRCT into a chronic disease.

The Stehlin Foundation[13] currently offers DSRCT patients the opportunity to send samples of their tumors free of charge for testing. Research scientists are growing the samples on nude mice and testing various chemical agents to find which are most effective against the individual's tumor.

Patients with advanced DSRCT may qualify to participate in clinical trials that are researching new drugs to treat the disease.

The Cory Monzingo Foundation is a 501(c)(3) organization that supports the research for treatments and a cure for DSRCT. The Cory Monzingo Foundation provides funding to MD Anderson Cancer Center and may also provide funding to other nonprofit cancer research organizations.

In 2002, Nishio and al[14], established a novel human tumor cell line derived from the pleural effusion of a patient with a typical intra-abdominal DSRCT, called JN-DSRCT-1[15] that can now be used in research.

St. Jude Children’s Research Hospital has, in 2018, make available resources from the Childhood Solid Tumor Network, that upon request gives access to patient-derived orthotopic xenografts[16].

This disease is also known as: desmoplastic small round blue cell tumor; intra-abdominal desmoplastic small round blue cell tumor; desmoplastic small cell tumor; desmoplastic cancer; desmoplastic sarcoma; DSRCT.

There is no connection to peritoneal mesothelioma which is another disease sometimes described as desmoplastic.

• Kate Granger (1981–2016), an English physician, whose diagnosis with DSRCT led to her campaigning for better patient care, and fund-raising for cancer research.