|Year : 2015 | Volume
| Issue : 3 | Page : 664
Primitive neuroectodermal tumor of the prostate: Case report from China
Chunli Liao1, Xingcheng Wu2, Xiaojing Wang1, Hanzhong Li2
1 Department of Medical Services, Peking Union Medical College Hospital, Beijing, China
2 Department of Urology Surgery, Peking Union Medical College Hospital, Beijing, China
|Date of Web Publication||9-Oct-2015|
Department of Urology Surgery, Peking Union Medical College Hospital, Dongdan, 1 Shuaifuyuan, Beijing 100730
Source of Support: None, Conflict of Interest: None
Peripheral primitive neuroectodermal tumor (PNET) in the prostate is one of the most aggressive tumors and a rare, uncommon clinical disease entity with a very poor prognosis. We reported a case of PNET in the prostate of a 49-year-old man and diagnosed through a biopsy. The patient underwent chemotherapy followed by adjuvant external radiation therapy without cystoprostatectomy as recommended, and 2 years later there is no sign of recurrence or distant metastasis. The patient had a good recovery and satisfactory outcomes in the follow-up. The successful treatment of PNET in the prostate in our case without surgery will provide a good therapeutic regime for reference until now.
Keywords: Chemotherapy, primitive neuroectodermal tumor, radiotherapy, the prostate
|How to cite this article:|
Liao C, Wu X, Wang X, Li H. Primitive neuroectodermal tumor of the prostate: Case report from China. J Can Res Ther 2015;11:664
| > Introduction|| |
Peripheral primitive neuroectodermal tumor (PNET) is primarily occurring in soft tissues and bones, with malignant proliferations of small undifferentiated neuroectodermal cells. Cases of PNET have been mainly reported arising from the visceral sites such as brain, parotid gland, lung, kidney, urinary bladder, uterus, pancreas, and testis, rarely in prostate.  As far as our knowledge is concerned, only seven cases of PNET have been reported in the prostate. ,,,,,,, And there is no data available about PNET in the prostate in literature from China. We report a case of a 49-year-old PNET patient diagnosed by tru-cut biopsy from the prostate mass and immunohistochemistry (IHC). Despite of the poor outcome the current literature illustrated, our patient survives >2 years, treated by 6 cycles of chemotherapy based on vincristine, ifosfamide, doxorubicin, and etoposide protocol and full-round external radiotherapy (RTx) (at a dose of 60 Gy, 200 cGy/day, 5 days a week, three-dimensional conformal RTx).
| > Case report|| |
A 49-year-old man presented with a 1-year history of frequent urination, dysuria, pelvic discomfort, and weight loss. He had no documentation of any major illness or malignancy disease before. On physical examination, the prostate was very large and the mass was hard and palpable with poor mobility. The patient's serum prostate-specific antigen level and carbohydrate antigen series were within normal ranges. Neuron-specific enolase (NSE) level was 19.3 ng/ml. Computed tomography (CT) scan revealed prostate was enlarged with inhomogenous enhancement about 7.1 cm × 6.5 cm × 5.0 cm. The tumor was in close contact with the bilateral seminal vesicle [Figure 1]. Magnetic resonance imaging (MRI) showed mass lesion was arising from prostate and extending exteriorly recta with no signs of enlargement of lymph nodes. Positron emission tomography-CT (PET-CT) confirmed the findings of MRI and no distant metastasis.
|Figure 1: Computed tomography scan of the pelvic region showing the tumor mass in the prostate gland before chemotherapy, involved with the bilateral seminal vesicle|
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A biopsy of the prostate was performed, which revealed a malignant PNET. IHC showed positive CD99, CD56, and NSE with Ki-67 70%, consistent with PNET of prostate. Chemotherapy based on vincristine, adriamycin, and cyclophosphamide with ifosfamide and etoposide was planned. The patient had slight side effects of moderate liver functional damage with alanine transaminase maximum 71 U/L during the chemotherapy, and the supporting treatment was given. Until June in 2012 when the succeeding six rounds of chemotherapy were finished. CT scan showed the mass shrank to 4.2 cm × 5.0 cm × 4.5 cm, and then full-round external RTx was added afterwards. The three-dimensional conformal RTx radiation was given at a dose of 60 Gy, 200 cGy/day, 5 days a week. Subsequent CT scan in January, 2013, revealed that the prostate showed a remarkable reduction in size [Figure 2], about 3.5 cm × 3.5 cm × 4.0 cm and the biopsy of the prostate was reperformed, showing no sign of tumor recurring. PET-CT was rechecked displaying no evidence of distant metastasis. NSE was back to normal.
|Figure 2: Computed tomography scan of the pelvic region showing the tumor mass in the prostate gland after six rounds of chemotherapy and full-round external radiotherapy|
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| > Discussion|| |
Primitive neuroectodermal tumor in the prostate is extremely rare, accounting for <0.1% of the primary prostate cancer types in adults, especially in the young man aged between 35 and 60.  In the only eight reported cases up to date, only one of those patients who undertook only combination chemotherapy consisting of ifosfamide, doxorubicin, vincristine, and etoposide was reported surviving without evidence of distant metastasis, just as our patient did [Table 1].
|Table 1: The features of primitive neuroectodermal tumor of prostate reported to date compared with our case|
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Diagnosis of PNET in the prostate is full of challenge. The patients often described exactly the same chief complaints as the patients with benign prostatic hyperplasia did. The CT and MRI findings provided with the evidence of a heterogeneously enhanced mass in all cases. And the further biopsy with IHC is required to confirm the diagnosis. Prostate biopsy specimens showing a segmented mass of uniform small cells and immunoreactivity for CD99, as well as for NSE, CD56 are key to diagnosing a primary PNET of the prostate as they did in all the other cases. ,,,,,,, Indeed, considering its rare occurrence and the nonspecific imaging features of PNET, biopsy with IHC should be considered initially in case of delaying the illness, especially when it comes to a large retroperitoneal mass with aggressive characteristics. Hence, molecular studies with IHC are the gold standard for an accurate diagnose in such cases.
Primitive neuroectodermal tumor in the prostate is considered to be aggressive with poor outcomes. There are three patients in the eight cases reported showed good response to chemotherapy and then extended surgeries [Table 1]. ,,,,,,, Three of the patients were reported to be successfully treated chemotherapy consisting of ifosfamide, doxorubicin, vincristine, and etoposide, and two of them received combined RTx, as our patient did. But none of them was reported to achieve longer disease-free time than our case, in which our patient was 2 years disease-free after treatment. It seems that the combination treatment of chemotherapy and RTx can achieve the same results as the typical treatment of chemotherapy extending surgery, which is recommended to be the most appropriate treatment.  Surgery was considered to be the best mode of local disease control.  PNET is a radiosensitive tumor. Dunst reported RTx was as effective in overall survival as surgery or combination of RTx and surgery in 177 patients with localized Ewing's sarcoma.  Radiation may have the same role in improving local disease control in patients with PNET. In our case, the patient does not want surgery. Still we managed to control PENT with systemic chemo plus RTx without surgery, which suggested that radiation may have good local disease control. Despite of the temporary success, optimal management of this tumor is still unknown, and the results are not promising. Response to chemotherapy is one of the most important prognostic factors. One of the eight patients was first given with vincristine and doxorubicin, then switched to second line chemotherapy with docetaxel and gemzar due to nontolerance of primary drugs. After showing no response with second-line chemotherapy, the patient was given third-line chemotherapy with ifosphamide. Four months later, his disease progressed, and he gave up.  Available information little regards the upmost therapeutic options for PNET, and newer protocols need to be evaluated to optimize chemotherapeutic response in patients with PNET. Nevertheless, our patient survived without the resection surgery of the tumor, so the best treatment for the patients with PNET in the prostate is still debatable, while the patient can have another effective option of treatment as the patient did in our case.
In summary, we report a rare, uncommon case of PNET arising from the prostate in China. As it is easily overlooked for its occurrence, an accurate diagnose is based on biopsy with IHC. Combination chemotherapy consisting of ifosfamide, doxorubicin, vincristine, and etoposide, and adjuvant radiation therapy is effective in the treatment for the patients with PNET in the prostate in our case without resection of the tumor. In our case, we provided a successful therapeutic regime for reference until now.
| > References|| |
Dehner LP. Peripheral and central primitive neuroectodermal tumors. A nosologic concept seeking a consensus. Arch Pathol Lab Med 1986;110:997-1005.
Peyromaure M, Vieillefond A, Boucher E, De Pinieux G, Beuzeboc P, Debré B, et al
. Primitive neuroectodermal tumor of the prostate. J Urol 2003;170:182-3.
Colecchia M, Dagrada G, Poliani PL, Messina A, Pilotti S. Primary primitive peripheral neuroectodermal tumor of the prostate. Immunophenotypic and molecular study of a case. Arch Pathol Lab Med 2003;127:e190-3.
Thete N, Rastogi D, Arya S, Singh A, Rao P, Chandge A, et al
. Primitive neuroectodermal tumour of the prostate gland: Ultrasound and MRI findings. Br J Radiol 2007;80:e180-3.
Kumar V, Khurana N, Rathi AK, Malhotra A, Sharma K, Abhishek A, et al
. Primitive neuroectodermal tumor of prostate. Indian J Pathol Microbiol 2008;51:386-8.
Funahashi Y, Yoshino Y, Hattori R. Ewing's sarcoma/primitive neuroectodermal tumor of the prostate. Int J Urol 2009;16:769.
Mohsin R, Hashmi A, Mubarak M, Sultan G, Shehzad A, Qayum A, et al
. Primitive neuroectodermal tumor/Ewing's sarcoma in adult uro-oncology: A case series from a developing country. Urol Ann 2011;3:103-7.
Al Haddabi I, Al Bahri M, Burney I. Cytokeratin-positive primitive neuroectodermal tumor of the prostate: Case report and review of literature. Indian J Pathol Microbiol 2012;55:569-71.
Wu T, Jin T, Luo D, Chen L, Li X. Ewing's sarcoma/primitive neuroectodermal tumour of the prostate: A case report and literature review. Can Urol Assoc J 2013;7:E458-9.
Paulussen M, Fröhlich B, Jürgens H. Ewing tumour: Incidence, prognosis and treatment options. Paediatr Drugs 2001;3:899-913.
Dunst J, Jürgens H, Sauer R, Pape H, Paulussen M, Winkelmann W, et al
. Radiation therapy in Ewing's sarcoma: An update of the CESS 86 trial. Int J Radiat Oncol Biol Phys 1995;32:919-30.
[Figure 1], [Figure 2]