Renal Primitive Neuroectodermal Tumor Research Articles

Uncommon suspect: A case report of a rare renal neoplasm

Primitive neuroectodermal tumors (PNETs) are a group of rare and aggressive malignancies primarily found in children and young patients. Primary renal PNETs are very much uncommon and share clinical and radiological features with renal cell carcinoma (RCC), thus posing a significant diagnostic and therapeutic challenge. This case report presents the clinical, radiological, and pathological findings of a primary renal PNET in an adult female patient, mimicking the radiological appearance of RCC.

Renal primitive neuroectodermal tumor in an adolescent: a case report and review of literature

Renal primitive neuroectodermal tumor is a highly malignant neoplasm that commonly affects young adults and infrequently presented in children and adolescents. We report a case of a 14-year-old female child who presented with abdominal mass. PET-CT showed an FDG avid cystic lesion in the inter and lower polar regions of the right kidney, extending into the right renal fat and renal vein, with multiple FDG avid lesions in the axial and appendicular skeleton, suggesting renal mass with bony metastases. Biopsy confirmed the diagnosis of primitive neuroectodermal tumor of the kidney. The patient completed six cycles of chemotherapy with partial response and subsequently the patient defaulted and lost to follow-up. To emphasize the critical significance of renal PNET in the differential diagnosis of renal tumors in children.

Renal primitive neuroectodermal tumor: A rare case with a good prognosis.

Renal primitive neuroectodermal tumor (rPNET) has the characteristics of a difficult preoperative diagnosis, a high degree of malignancy, easy early metastasis or postoperative recurrence, a poor prognosis, and so on. However, rPNET that has no metastasis before surgery can have a good survival prognosis only after radical surgical resection. We report the case of a 14-year-old male patient with a renal tumor who underwent open radical left nephrectomy without radiotherapy or chemotherapy before or after surgery, as confirmed by postoperative pathological results. The prognosis was followed up by a regular review of the chest and whole abdomen on CT, hematuria analysis, renal function, and electrolytes according to the guidelines for renal cancer. Postoperative pathological results confirmed rPNET; no adjuvant radiotherapy or chemotherapy were performed after surgery; no tumor recurrence or metastasis were observed during the follow-up of nearly 5 years. Despite the high degree of rPNET malignancy, patients without metastases before surgery can still obtain a good survival prognosis through timely radical surgery.

Renal Primitive Neuroectodermal Tumor or Renal Ewing Sarcoma

Renal primitive neuroectodermal tumor (renal PNET) or renal Ewing sarcoma (renal ES) is a rare, rapidly growing malignant small round cell tumor with poor prognosis. A 32-years-old Bangladeshi male patient presented with right loin pain, fever and anemia. On CT imaging a large (18x10.5x10.0 cm) renal mass was discovered. On suspicion of malignancy, a biopsy was taken from the mass. Microscopic evaluation showed features consistent with malignant small round blue cell tumor. Immunohistochemical stains showed diffuse and strong positive reaction to CD-99 and negative for WT-1, CD-3 and CD-20, which confirmed the diagnosis of renal PNET. After 6 cycles of combined chemotherapy, the patient was relatively well and at 6 months follow-up he showed no evidence of metastasis or recurrence.
 KYAMC Journal Vol. 13, No. 04, January 2023: 257-260

Renal primitive neuroectodermal tumor. The first case series from Syria.

Primitive neuroectodermal tumor (PNET) mainly arises from soft tissues of the extremities such as humerus, femur, C tibia. It rarely arises from kidney; less than 200 cases have been reported in the literature. The clinical presentation and radiography findings are not specific. Here we first report two cases of renal primitive neuroectodermal tumor in Syria.the first patient was 26-year-old- female that presented to urology clinic complaining of right flank pain. Ultrasonography of the abdomen showed a large mixed heterogeneous mass in the right kidney with no hemorrhage or calcification and MSCT of abdomen and pelvis demonstrate a mixed well-demarcated heterogeneous mass measuring (74*117) mm in the right kidney right radical nephrectomy was performed.The second patient 19-year-old-male presented with left flank pain. Ultrasonography of the abdomen showed mixed large mass involving the left kidney, with unmarked border. The CT of the abdomen and pelvis demonstrating a (30*110*90) mm left renal mass and periaortic lymphadenopathy measuring (45*28) mm. The patient underwent Left radical nephrectomy with periaortic lymphadenectomy dissection. The final diagnosis for both cases was Renal PNET based on microscopic and immunohistochemistry examination.In patient with suspected renal mass in the radiographic images, the diagnosis of renal primitive neuroectodermal tumor should be kept in the mind despite its rarity. The final diagnosis is done by histopathological study in association with immunohistochemical examination.

Primitive neuroectodermal tumor of the kidney: an experience of three cases

BackgroundPrimitive neuroectodermal tumors (PNET) are highly aggressive tumors belonging to the Ewing’s sarcoma family. Primitive neuroectodermal tumor is a group of bone and soft tissue tumor arising from neuroectodermal tissues. They are characterized by the expression of MIC2 and neural markers like neuron-specific enolase, synaptophysin, S-100, vimentin, Leu-7, and the presence of the EWS-FLI1 translocation. It is a rare malignancy with only about 150 cases being published worldwide. The tumor usually presents with non-specific symptoms such as abdomen pain and hematuria. Inferior vena cava (IVC) involvement by renal PNET is extremely rare with only a handful cases reported in the literature and is a clinically challenging scenario. There is a dearth of data on the management of this disease; further, the management of this disease in current scenarios is not well reported. We report our experience with three cases over 11 years which spans all three spectrums of the disease: localized, locally advance and metastasis. Case presentationCase 1: 37-year-old gentleman presenting with hematuria found to have right renal tumor with IVC invasion which was found to be unresectable intraoperatively. Patient was started on chemotherapy but deteriorated and died 3 months later. Case 2: 38-year-old gentleman presenting with abdominal pain found to have locally advanced left renal tumor. Patient developed local recurrence and metastasis 15 months after resection but had stable disease for nearly 4 years before developing acute myeloid leukemia and withdrawing consent for treatment. Case 3: 13-year-old girl who presented with right abdominal mass and subsequently found to have localized disease. After aggressive chemotherapy, patient is now recurrence-free after nearly 11 years.ConclusionsOur study aims to show the spectrum of renal primitive neuroectodermal tumors with outcomes in all three clinical scenarios, with the aim of reinforcing that high index of suspicion for this disease is required in young patients presenting with aggressive disease, and immunohistochemistry should be used when in doubt, as outcomes are greatly improved with adjuvant chemotherapy.

Primary primitive neuroectodermal tumour of the kidney in adults: Experience of managing 12 cases with systematic review and pooled analysis of literature.

Primitive neuroectodermal tumor (PNET) of the kidney is unusual in adults. These tumours are diagnosed mainly on histopathology and that too sometimes has limitations. With this study, we aimed to review our clinical and histopathological data of patients with renal PNET and reviewing the world literature. In this retrospective study, we reviewed our database from January 2006 to July 2018 to include all the cases of primary PNET of the kidney. We also performed systematic literature search to identify all the relevant series on renal PNET. A total of 12 patients including 5 men and 7 women were managed during the above mentioned period. Out of these 7 patients, 2 patients had metastasis at diagnosis, one had locally advanced disease, 6 underwent radical nephrectomy, 5 patients received adjuvant chemotherapy (two currently receiving) and only 1 patient received adjuvant radiotherapy (RT). On Immunohistochemistry (IHC), CD99 and FLI1 were positive in all the patients. Median survival was 10months. In our review 10 studies were included, 38.6% of the patients had metastatic disease and 10.7% had locally advanced disease at diagnosis. Overall mean survival was 33.75months. CD99 and FLI1 were positive in 94.3% and 78.5%, respectively. PNET remains a pathological diagnosis and IHC has important place in diagnosis of PNET. Locally advanced and metastatic disease is common at diagnosis leading to overall poor survival.

Renal Primitive Neuroectodermal Tumor With Inferior Vena Cava Thrombus: Case Series and Literature Review of a Rare but Challenging Entity.

To investigate the clinicopathological characteristics, treatments, and prognosis of patients with renal primitive neuroectodermal ectodermal tumors (rPNETs) with inferior vena cava (IVC) tumor thrombus. We retrospectively reviewed 6 patients with rPNETs and IVC tumor thrombus between January 2005 and December 2019, and identified 39 published cases through a literature review. The clinicopathological characteristics, treatments, and survival data were analyzed. The median patient age patients was 26 years, and the male to female ratio was approximately 1:1. The average tumor diameter was 12.5 cm. Seventeen patients (37.8%) showed metastasis at diagnosis. Forty-three cases (95.6%) were managed with surgical resection, and 35 (77.8%) received adjuvant chemotherapy after surgery. Follow-up data were available for 41 patients (median follow-up, 10 months; range, 4.5-13.0). The median overall survival (OS) and median progression-free survival (PFS) were both 30.0 months. Patients who received adjuvant chemotherapy had better PFS than those who underwent surgery only (30.0 months [95% confidence interval [CI], 4.3-55.7] vs 5.0 months [95% CI, 1.0-9.0]; P=.036). In terms of OS, however, the difference between the 2 groups was not significant (30.0 months [95% CI, 8.4-52.6] vs 7.0 months [95% CI, 4.5-9.5]; P=.244). rPNET with IVCTT is an extremely rare entity that mostly occurs in young adults. Although multidisciplinary treatment is used, the prognosis of this disease remains unclear. RN with IVC tumor thrombectomy is a challenging procedure requiring vascular management techniques and experience. Adjuvant chemotherapy contributes to improved PFS, but not OS. Thus, early diagnosis and treatment play a key role in improving prognosis.

A retrospective study of primitive neuroectodermal tumor (PNET) of the kidney in a tertiary cancer center in India.

361 Background: Primitive neuroectodermal tumours (PNET) of the kidney are rare tumours with aggressive behaviour. This study was conducted to review the diagnosis and management of patients with renal PNET at our centre. Methods: This was a retrospective study conducted at a tertiary cancer care centre in Mumbai, India. The demographic and clinical data of 17 patients treated by the uro-oncology services were retrieved from electronic medical records. Descriptive analysis was performed for baseline characteristics.Overall & progression-free survival was determined using the Kaplan Meier method. Cox regression was used for multivariate analysis. Results: There were 12 male and 5 female patients in this cohort with a median age of 27 years. At diagnosis 2 patients had metastatic disease and 15 patients had non-metastatic disease. Median follow up in this cohort was 22 months (range 2-30 months). Presenting complaints were hematuria, abdominal pain, flank pain, fever, bone pain, and incidentally detected renal mass. All patients were Mic -2 positive and 13 were FLI-1 positive on immunohistochemistry. Fourteen patients underwent radical nephrectomy. One (5.9%) patient received both neoadjuvant and adjuvant chemotherapy, 8 (47.1%) received adjuvant and 2 (11.8%) received palliative chemotherapy upfront. Eight patients received adjuvant radiation to the renal bed.There was disease progression in12 patients,10 of 15 patients with non metastatic disease at diagnosis eventually developed metastasis.The median progression free survival (PFS) was 10.55 months.The pathological feature that was associated with a shorter PFS was tumor size ⩾10 cm(p = 0.044).The median overall survival was 20.04 months (95% CI 9.49 -not reached). The presence of metastasis and treatment received significantly impacted overall survival (OS). Median OS in patients with non-metastatic disease was not reached versus 14.1 months in those with metastatic disease (p = .019).The median OS in patients treated with multimodality approach was 20.11 months. Patients did not undergo surgery had a median OS of 5.45 months (p < .001) and those who did not receive any chemotherapy had a median OS of 4.57 months (p = .024).Thus, patients who received multimodality treatment had better outcomes. Conclusions: PNET kidney is an aggressive tumor which should be treated with a multimodality approach. Tumor size ⩾10 cm was an adverse prognostic factor.

Renal Ewing's sarcoma/primitive neuroectodermal tumor (PNET): a case series of 7 patients and literature review.

BackgroundPrimitive neuroectodermal tumor (PNET) is a rare kind of sarcoma that is primarily found in the kidney and has a very poor prognosis. Here, we review and summarize the clinical data of patients with renal PNET in our center and follow up the patients for survival status. Although the current literature suggests that chemotherapy may benefit the survival of these patients, the information from our center suggests that this may not be the case.MethodsWe retrospectively analyzed the clinical data of patients with renal PNET diagnosed pathologically at Peking University First Hospital from January 1, 2007, to January 1, 2018. All of the patients were followed up for survival status.ResultsSeven patients with renal PNET were found. The ratio of males to females was 6:1. The median age was 29 years (21–72 years) at the time of diagnosis. The preoperative imaging examination showed a large renal mass protruding outwards from the renal contour, with internal necrosis and hemorrhage. Six/7 patients were diagnosed with distant metastasis or retroperitoneal lymph node metastasis. The main clinical manifestations of patients were pain (5/7) and fever (3/7). In immunohistochemistry, all patients’ samples were CD99 positive. All patients died in our follow-up, with an average overall survival (OS) of 12.09 months (1.90–26.77 months).ConclusionsAs a rare renal tumor, renal PNET has a propensity to occur in young males. Most patients have distant metastasis when they are diagnosed, and the prognosis is very poor. Effective treatments are urgently needed.

Primary primitive neuroectodermal tumor of the kidney: A rare case report and review of literature

Primitive neuroectodermal tumors (PNET) is an aggressive, rapidly progressing and metastatic tumor. It rarely arises from the kidney and has an incidence of less than 1%. These are usually mistaken for a wide variety of other small round cell tumors. Young adults and children are commonly affected and have an aggressive course. These tumors are mistaken for a wide variety of other small round cell tumors. Here is a case of a 52-year-old female, who presented with flank pain and gross hematuria. The contrast-enhanced computerized tomogram (CECT) revealed a renal mass with a tumor thrombus extending to the renal vein, inferior vena cava, and the right side of the heart. The patient underwent radical nephrectomy along with IVC thrombectomy and chemotherapy. The sections from formalin-fixed surgical specimens were paraffin-embedded and stained with H & E stain. Immunohistochemistry (IHC) was performed.Histology revealed small round to oval cells with hyperchromatic nucleus and very scanty cytoplasm. Frequent mitotic figures were noted. Few rosettes were seen at places. Tumor was seen invading the perirenal adipose tissue. The tumor thrombus extended into the right atrium and the right ventricle. IHC evaluation revealed the tumor cells showed a strong positivity for CD99, synaptophysin, neuron-specific enolase, vimentin, and were negative for CD45, pan-cytokeratin, and desmin. Thus, the histological examination and IHC helped in getting a definite diagnosis of PNET involving the kidney. The patient has been undergoing chemotherapy. PNET has an aggressive clinical course with a poor prognosis. Renal PNET bears many similarities to other small round cell tumors; hence it is important to review the histologic features and immunostaining for definitive diagnosis. Due to the rarity of the disease, there is no standard guideline regarding its management. Achieving accurate diagnosis facilitates the prolongation of survival with definitive treatment.

Do Primitive Neuroectodermal Tumors of the Kidney Have a Predilection for Inferior Vena Cava Involvement?

The primitive neuroectodermal tumor (PNET) of the kidney is an extremely rare neoplasm, the diagnosis of which mainly depends upon his-topathology, immunohistochemistry (IHC), and cytogenetics. A handful of cases reported in the literature mention about aggressive features of this neoplasm. The purpose of our study was to review our experience in not only the diagnosis and management of the patients with renal PNET but also to highlight its propensity to involve inferior vena cava (IVC) and also present a rare occurrence of Ewing’s sarcoma (ES)/PNET of the renal pelvis.The clinical, operative, and histopathology records of four patients of renal PNET treated between January 2017 and December 2019 were reviewed and data analyzed concerning the available literature. Out of the four patients treated, two had level III and IV IVC thrombus, and one had dense desmoplastic adhesions with the IVC wall. One of the cases had a rare presentation of ES/PNET of the renal pelvis. All patients were managed surgically, while only one patient received adjuvant chemotherapy and following up with remission for the last 2 years and 4 months. On IHC, cluster of differentiation-99 (CD-99) was positive in all patients, and three were positive for Friend leukemia integration-1. PNET of the kidney is primarily an immunohistopathological diagnosis. This neoplasm has an increased propensity for the local invasion of surrounding structures. A multimodality approach with surgery, chemotherapy, and radiotherapy could offer better outcomes, although the prognosis of these tumors remains poor.

Second New Primary PNET of Kidney in a Treated Case of Carcinoma Breast: A Case Report

Primitive Neuroectodermal Tumour (PNET) is a member of small round cell “Blue tumour” family. The overall incidence of PNET is <1%. PNET of kidney is uncommon and was first reported in 1975. Since the first report around 150 cases have been published in medical literature. It exhibits highly aggressive behaviour. It usually affects young adults and has a male predominance of 3:1. Only six cases of PNET of kidney have been reported in older patients and PNET of kidney as a second new primary has rarely been reported, only three cases of renal PNET with history of an earlier or synchronous primary cancer were reported in literature from the USA, Germany and China. Here, the author reported a case of renal PNET in a 48-year-old female who has been treated for right breast cancer by surgery, adjuvant chemotherapy and radiotherapy three years (July 2015) prior to diagnosis of PNET of left kidney. Upon diagnosis, patient underwent left nephrectomy. Postoperatively, patient was started on Ewing’s Family of Tumours (EFT) 2001 protocol. Patient completed induction therapy followed by radiation to tumour bed with concurrent weekly single agent vincristine and was planned for maintenance chemotherapy. After one cycle of maintenance chemotherapy, patient developed severe febrile pancytopenia and was admitted in the ICU, even after aggressive medical line of management, patient could not be revived. Although, the patient tolerated the treatment protocol for breast malignancy well and the primary was under control but after three years, with the diagnosis of a very rare second new primary PNET of left kidney which has a very aggressive nature and poor prognosis, the patient could not tolerate the multimodality treatment which was required.

Primary Pediatric Renal Primitive Neuroectodermal Tumor: A Case Report With Different Stage CT and MRI Images

Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) of the kidney in children younger than 10 years of age is extremely rare. We describe here the case of a 7-year-old female patient who was diagnosed with ES/PNET. The timeframe for this case spanned from 8 months prior to diagnosis until 8 months postsurgical removal of the tumor. In addition, we summarized the cases of PNET in children younger than 10 years of age in the last decade.

Ewing sarcoma/primitive neuro-ectodermal tumor of the urogenital system in children: a retrospective observational case series

Pediatric Ewing sarcoma (ES)/primitive neuro-ectodermal tumor (PNET) occurring in the genitourinary system has been rarely reported. And the result of long-term follow-up is still a matter of debate. The aim of the study was to identify the characteristics, therapeutic strategies, and long-term outcomes of pediatric ES/PNET in the genitourinary system. All children with genitourinary system PNET from a single center were retrospectively reviewed. The American Joint Committee on Cancer (AJCC) staging system was used to evaluate tumor grade. Four patients were included. Three were boys, and 1 was a girl. The locations of the lesions were the penis in 1 patient, ureter in 1 patient, and kidney in 2 patients. Two patients were of AJCC stage IVB, and the other 2 patients were of stage IIA. In the follow-up ranging from 2.5 to 8.0 years, 3 patients had survival, and 1 patient died. The patient with penis PNET survived during the 8 years of follow-up. One patient with renal PNET had tumor thromboses in the renal vein, inferior vena cava, and right atrium, which was the first definite report in children (case 3). Primitive neuro-ectodermal tumor as a highly malignant subgroup of blue round cell tumor is extremely rare in the genitourinary system, especially in children. The current case series represents the first report of penis PNET in children with the longest (8 years) follow-up and first definite report of pediatric renal PNET with vena cava and atrium tumor thrombus. In contrast to the previous literature, the patient with ureteral PNET in this study was much younger, who was the youngest child to be reported in the literature thus far. Although the key prognostic factor of the outcomes is detectable metastases at diagnosis, the patient with penis PNET and bone and lung metastasis in this series still survived. It was hypothesized from the data of present cases that young age was a protective factor, which was consistent with the previous literature. Aggressive therapy is not trivial for patients with multiple recurrences who can also be a long-term survivor. The survival outcomes of these high-stage patients were favorable with combination treatment. As the patient with penis PNET in this series had bone metastasis at his 7.5 years after definite diagnosis, five years of follow-up was not enough. The follow-up period should be extended, even to a lifetime follow-up. Children with PNET have a better prognosis than adults. Aggressive combination treatment should be performed to improve prognosis and the survival rate. It is better to monitor the changes of the disease by extending the follow-up period.

Renal primitive neuroectodermal tumor (RPNET) in children

Renal primitive neuroectodermal tumor (rPNET) as a member of Ewing’s sarcoma family is extremely rare and usually occurs in children and young adults. Most literature about rPNET was isolated case reports. Here we described a case of renal PNET in a 7-year-old girl who presented at our Paediatric Surgery Department of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh with fever, left flank pain and mass Ultrasonogram (USG) and Computer tomography (CT) scan revealed a huge mass in the left kidney. The patient underwent left radical nephrectomy with neoadjuvent chemotherapy on April,2016. Histopathology and immunohistochemistry (IHC) confirmed the diagnosis of PNET. She did not receive adjuvant chemotherapy, as advised. She had a local tumor recurrence 3 months after the surgery and continued to deteriorate but not developed distant metastasis. She again received 2-cycle of chemotherapy but size did not decrease. So re-do surgery was performed on 10.01.2017 and send to paediatric haemato-oncology department of BSMMU for further management. rPNET is rare and presents aggressive clinical behavior and worse prognosis. We expect that further awareness and study of this rare tumor can be had by presenting our case.
 Journal of Paediatric Surgeons of Bangladesh (2016) Vol. 7 (2): 66-71

Qualitative and quantitative CECT features for differentiating renal primitive neuroectodermal tumor from the renal cell carcinoma and its subtypes.

To identify important qualitative and quantitative clinical and imaging features that could potentially differentiate renal primitiveneuroectodermal tumor (PNET) from various subtypes of renalcell carcinoma (RCC). We retrospectively reviewed 164 patients, 143 with pathologically proven RCC and 21 with pathologically proven renal PNET. Univariate analysis of each parameter was performed. In order to differentiate renal PNET from RCC subtypes and overall RCC as a group, we generated ROC curves and determined cutoff values for mean attenuation of the lesion, mass to aorta attenuation ratio and mass to renal parenchyma attenuation ratio in the nephrographic phase. Univariate analysis revealed 11 significant parameters for differentiating renal PNET from clear cell RCC (age, p = <0.001; size, p =< 0.001; endophytic growth pattern, p < 0.001;margin of lesion, p =< 0.001; septa within the lesion, p =< 0.001; renal vein invasion, p =< 0.001; inferior vena cava involvement, p = 0.014; enhancement of lesion less than the renal parenchyma, p = 0.008; attenuation of the lesion, p = 0.002; mass to aorta attenuation ratio, p =< 0.001; and mass to renal parenchyma attenuation ratio, p =< 0.001). Univariate analysis also revealed seven significant parameters for differentiating renal PNET from papillary RCC. For differentiating renal PNET from overall RCCs as a group, when 77.3 Hounsfield unit was used as cutoff value in nephrographic phase, the sensitivity and specificity were 71.83 and 76.92 % respectively. For differentiating renal PNET from overall RCCs as a group, when 0.57 was used as cutoff for mass to aorta enhancement ratio in nephrographic phase, the sensitivity and specificity were 80.28 and 84.62 % respectively. Specific qualitative and quantitative features can potentially differentiate renal PNET from various subtypes of RCC. The study underscores the utility of combined demographic and CT findings to potentially differentiate renal PNET from the much commoner renal neoplasm, i.e. RCC. It has management implications as if RCC is suspected, surgeons proceed with resection without need for confirmatory biopsy. On the contrary, a suspected renal PNET should proceed with biopsy followed by chemoradiotherapy, thus obviating the unnecessary morbidity and mortality.

Primitive neuroectodermal tumor of the kidney at the advanced stage: A case series of eight Chinese patients.

Primitive neuroectodermal tumor (PNET) rarely occurs as a primary renal neoplasm. Renal (r)PNET is a rare but aggressive neoplasm with poor prognosis; the majority of patients are diagnosed as advanced stage at presentation and face a worse prognosis than patients with localized disease. The present study describes the diagnosis and management of eight cases of rPNET at an advanced stage, who were treated at two institutions [Lingnan Hospital (branch of The Third Affiliated Hospital) and the Cancer Center of Sun Yat-sen University, Guangzhou], from December 2004 to January 2013. The clinical and pathological results of all patients were retrospectively obtained. Kaplan-Meier analysis was performed to estimate patient survival. The study cohort comprised five males and three females. Radical nephrectomy was performed in seven cases, while the remaining case only received needle biopsy of the tumor. Five cases received adjuvant chemotherapy, while three received no further treatment after surgery. Of note, one case received cytokine-induced killer (CIK) cell immunotherapy combined with surgery and chemotherapy. The overall median survival was 20 months with a 3-year survival rate of 25%. The overall survival of the four patients who received adjuvant chemotherapy following surgery was 36 months, compared with 10 months in the three patients without further treatment. The patient who received CIK cell immunotherapy survived for 20 months. Based on the observations of the present and previous studies, surgical excision and chemotherapy are recommended for treating rPNET at advanced stage. Furthermore, the present study was the first to report on CIK cell immunotherapy for a patient with rPNET, indicating that it may be a promising optional treatment. However, further studies are required to validate the benefit of CIK cells and to establish an appropriate immunotherapy protocol.

Primitive neuroectodermal tumor of kidney and its rare affection for inferior vena cava

Primitive neuroectodermal tumors (PNETs) are a group of small round cell malignancies of neural crest origin. Renal PNET (rPNET) is a rare entity affecting young adults and children with a poor prognosis, and involvement of inferior vena cava (IVC) is extremely uncommon. Nonspecific clinical features often preclude preoperative diagnosis which ultimately depends on microscopy and immunohistochemistry. The preferred treatment for rPENT is surgical resection associated with chemotherapy and radiotherapy. We report a case of rPNET in a 16-year-old male which was preoperatively thought to be of renal cell carcinoma and underwent radical nephrectomy with IVC venotomy. The case on histopathology study revealed features of malignant small blue round cell neoplasm and further immunohistochemical examination diagnosed the case as rPNET.

Renal Primitive Neuroectodermal Tumor in a Child with Brain Metastasis: A Case Report

Primitive neuroectodermal tumor (PNET) is a malignant small round cell tumor that typically arises from bone or soft tissue in adolescents and young adults. Renal PNET is extraordinarily rare and exhibits highly aggressive biological behavior with poor prognosis. It generally occurs in young adults and only a few pediatric cases have been reported. Here, we present a case of renal PNET in an 11-month-old boy which developed brain metastasis after two years, despite combined modality treatment.