Primitive neuroectodermal tumour (PNET) of the kidney: a rare renal tumour in adolescents with seemingly characteristic radiological features

Abstract

While rare, one should consider the diagnosis of PNET when encountering a renal mass with aggressive features such as inferior vena cava tumour thrombus, direct intraspinal invasion and distant metastasis.

Renal Primitive Neuroectodermal Tumors

“…As previously discussed, renal PNETs typically occur in older children and young adults, 3,6,9,10 a different demographic than the more senior populations traditionally affected by clear cell renal cell carcinomas (RCCs), papillary RCCs, and chromophobe RCCs. 12 Patients with renal PNET may present with malaise, an increase in abdominal circumference, weight loss, nephric colic, fever, flank pain, hematuria, and night sweats.…”

“…2 As their name would suggest, PNETs arise from the cells of the primitive neuroectoderm. 3 Primitive neuroectodermal tumors may occur both within and outside of the central nervous system. 4 Most commonly, peripheral PNETs are found to arise in the chest wall and paraspinal regions.…”

“…4 Most commonly, peripheral PNETs are found to arise in the chest wall and paraspinal regions. 5 It is less common, although still possible, to see peripheral PNETs in the genitourinary system, as case reports have documented instances of their occurrence in the uterus, 3 epididymus, 3 and bladder. 6 To our knowledge, the first reported case of a PNET with a renal origin was in 1975, 7 although during the past decade, increasing numbers of case reports and case series have been documented, indicating that this entity may have been underreported or misdiagnosed in the past.…”

“…6,10 Both males and females have been shown to be affected, with some work documenting a predominance in males, 10 although this has not been universally confirmed. 3 Typically, whites and Hispanics are the most commonly affected by ES/PNET family tumors, with cases in blacks and Asians occurring rarely. 1 Renal PNETs present as very clinically aggressive tumors.…”

“…1 Renal PNETs present as very clinically aggressive tumors. 3,4,6,10 Cases of local recurrence and metastasis have been shown to comprise more than 50% of the clinical presentations in this cancer, 5 with the most common sites of metastasis shown to be the lymph nodes, lungs, and liver. 6 In a 2001 review of 25 cases of renal PNET, the mean patient survival was approximately 10 months.…”