Seminal vesicle carcinoma is a rare malignant tumor originating from the epithelium of seminal vesicle glands. A total of more than 100 cases diagnosed with this disease can be retrieved at home and abroad up to now. Due to the small number of cases, there is no clinical staging and specific surgical treatment plan about this disease to follow. The cause of this disease is not clear and the initial symptoms are not obvious, so early diagnosis is difficult and easy to misdiagnose. Our hospital from January 1996 to January 2008, a total of five cases of primary seminal vesicle malignant tumors, now combined with the relevant literature and our experience in the treatment of the disease of the surgical program and its selection of conditions, in order to provide some help to the treatment of this disease. 1.Data 5 patients aged 39~80 years old, average 62 years old, were admitted to the hospital for lower urinary tract obstruction and lower gastrointestinal tract symptoms, 1 case was accompanied by hematospermia, 1 case had the symptoms of prostatic vesicourethritis, accompanied by lumbosacral perineum spermatic cord testicles and anus drop discomfort and a dull pain sensation. Rectal fingerprinting can be found around the seminal vesicle prostate swelling, size from 1×2cm to 7×6cm ranging from different texture, or hard or soft. In one case, a 1×2cm hard nodule was palpated in one epididymis. Blood CEA, AFP, PSA were not abnormal. Imaging data ultrasound: bladder or posterior prostate or even urethral bladder can be seen as a mass of varying sizes, with unclear outline, nodular shape, and inhomogeneous light spots of cancerous nests inside. CT or MR: in the junction area of prostate and seminal vesicle, a mass of unequal size, maximum about 7×5.6×6cm, with inhomogeneous density is seen, the mass may protrude backward, the rectum is compressed and displaced, and the lumen of rectal canal is irregularly narrowed, the mass may also protrude from backward to forward and upward direction, and compress the bladder, or the mass may encroach into urethra to compress the urethra, and grow to the bladder from the urethra. The mass infiltrated into the surrounding tissues and organs, such as rectum, prostate, bladder and pelvic wall.No obvious metastasis was seen in the pelvic lymph nodes of the three patients. Bone scan did not show any tumor bone metastasis, and chest radiograph and ultrasound did not show any metastasis to other tissues and organs, such as lung, liver and spleen. Surgical approach and surgical scope: due to the large size of the tumor and the fact that all of them had already invaded to the surrounding tissues when they were found, we used the posterior bladder approach to perform seminal vesicle surgery. According to the size and extent of tumor invasion, 3 patients underwent resection of seminal vesicle tumor, bilateral seminal vesicles, part of the bladder, and prostate, 2 patients underwent radical resection of bilateral seminal vesicles together with bladder, prostate, and rectum (total pelvic resection), and bilateral orchiectomy. 5 patients underwent pelvic lymph node dissection. After resection of the mass and its invading organs, urethral reconstruction or urinary diversion was performed. 3 patients underwent anastomosis of the urethral stump to the residual part of the bladder, and 2 patients underwent ileal cystectomy. Postoperative pathology showed that one of the five patients had moderately differentiated seminal vesicle smooth muscle sarcoma, infiltrating the urethro-prostatic gland; one had indolent cell carcinoma, invading the rectum, bladder, prostate, and bilateral lower ureters; three patients had adenocarcinoma of seminal vesicles, which was poorly differentiated, and one of them had infiltrated the muscular layer of the rectal wall and the epididymis on one side. no lymph node metastasis was seen in any of the five patients. By summarizing the cases in this group and following them up, of the 5 patients we treated with radical surgery, 2 had no recurrence and metastasis within 5 years of postoperative follow-up, 1 had recurrence and distant metastasis 3 months after surgery, 1 died of recurrence 2 years after surgery, and 1 died of other diseases 3 years after surgery. Immunohistochemical detection of postoperative pathological specimens: 5 patients were negative for CEA, AFP, PSA, and 4 cases were positive for keratin and CA125. 3, Discussion Primary seminal vesicle malignant tumor is a rare malignant tumor originating from the seminal vesicle glands. Reviewing the literature, more than 100 cases have been reported abroad, and only 10 cases have been reported in China so far. The cause of this disease is not clear, but studies on mouse and guinea pig models have found that androgens seem to have a slight promoting effect on seminal vesicle cancer. This disease is mostly seen in the elderly, because seminal vesicles are located in the deep pelvis, the initial symptoms are not obvious, so early diagnosis is difficult, some patients may have different degrees of pelvic floor pain, urinary frequency, urinary urgency, urination difficulty, hematuria, spermatogonium and hematospermia, etc., and there may be changes in the fecal character if compression infringes on the rectum. Therefore, it is easy to be confused with prostate tumor and bladder tumor. Since carcinoma in situ of bladder, prostate cancer, rectal cancer and lymphoma are easy to infiltrate the seminal vesicles, it is difficult to identify whether the tumor originates from seminal vesicles. Histologically, primary seminal vesicle malignant tumors are mostly adenocarcinomas and sarcomas. The establishment of primary seminal vesicle malignant tumor must rely on a clear anatomical site and pathological confirmation that the center of the tumor is located in the seminal vesicles, and there is no primary tumor in the prostate and adjacent organs. Primary seminal vesicle malignant tumors are mainly treated by surgery, and there are not enough cases to confirm whether radiotherapy can improve the cure rate, and other adjuvant therapeutic options have not been proven to be effective. Since the seminal vesicle glands are androgen-dependent organs, as are the prostate glands, endocrine therapy has been advocated. Although the efficacy of this treatment has yet to be proven, most scholars tend to believe that radical surgery with debulking or estrogen therapy may be the best option for prolonging life. Primary seminal vesicle malignancies are insensitive to chemotherapy, and no effective chemotherapeutic agents have been found to be available. However, one case of small cell neuroendocrine tumor of the seminal vesicles admitted by E. C. Hoppin et al. was treated with chemotherapy that was effective early on and prolonged the patient’s survival. Therefore, different chemotherapeutic regimens may be considered for different seminal vesicle tumor origins, which may be effective in future treatment, although there is no uniformly effective chemotherapy regimen due to the limitation of the number of cases. Reviewing and analyzing primary seminal vesicle malignant tumors, we believe that they should be clinically staged according to the extent of their invasion for the formulation of surgical or therapeutic regimens. Tumors confined to the seminal vesicles should be considered early stage; invasion of the prostate, bladder, and rectum should be considered intermediate stage; and invasion of the pelvic wall or other distant metastases should be considered advanced stage. Surgery may be indicated for early and intermediate stages, and palliative surgery, such as surgery to relieve urinary tract obstruction or intestinal obstruction, and radiotherapy or chemotherapy may be indicated for advanced complete stages, depending on the needs of the disease. Reviewing and summarizing previously reported cases, the surgical approaches for primary seminal vesicle malignancy can be divided into three surgical approaches: simple vesiculectomy, radical resection and total pelvic resection. Clinicians can choose according to different clinical stages and the degree of tumor malignancy. In our opinion: ① simple vesiculectomy is suitable for small, highly differentiated tumors confined to the seminal vesicles, but due to the hidden nature of primary seminal vesicle tumors, most of the tumors have already invaded the surrounding tissues and organs when the patients consult the clinic, which is seldom seen in the clinic; ② radical resection is the procedure of removing bilateral seminal vesicles and the mass based on the degree of invasion of seminal vesicles and the bladder by seminal vesiculectomy and partial resection of the prostate and bladder or bladder according to the degree of invasion. Partial resection of the bladder or total cystoprostatectomy is performed according to the degree of invasion, while pelvic lymph node dissection is carried out; ③ Total pelvic resection is mainly seen when the seminal vesicle tumor invades the rectum at the same time to the back, in which case the pelvic organs such as bladder, prostate, rectum and seminal vesicles will be completely resected and pelvic lymph node dissection will be carried out at the same time. After radical resection and total pelvic resection, urinary tract reconstruction or urinary diversion is needed; ④ For the old and weak who cannot tolerate surgery or the tumor cannot be resected, radiotherapy can be carried out to alleviate the clinical symptoms and prolong the survival time; ⑤ For the seminal vesicle tumors of special tissue origins, a trial of corresponding chemotherapeutic regimens can be chosen according to the characteristics of the tumor. In our group, 5 cases of primary seminal vesicle malignant tumors were cured after active surgery in 2 cases, recurred in 2 cases, and died of other diseases during the follow-up period, which differed greatly from other reports at home and abroad, and was presumably due to the small number of cases. However, in these 5 cases, we found that although the primary seminal vesicle malignant tumor had an insidious onset and was found to have invaded the surrounding organs, none of them had lymph node metastasis or distant metastasis, and therefore, the surgical treatment was more effective. Does this group of cases also suggest that aggressive surgical treatment of primary seminal vesicle malignant tumors without distant metastases can achieve good results? Since there are less than 150 cases of primary seminal vesicle malignant tumors reported in the literature, and the number of cases in any treatment unit does not exceed 10, it is difficult to elucidate the optimal treatment plan. Summarizing the domestic and international literature, we found that lymphatic metastasis of primary malignant tumors of seminal vesicles is less than 5%, and invasion of peripheral tissues and organs reaches more than 50% at the time of consultation, so it is presumed that seminal vesicle tumors are predominantly infiltrated by peripheral tissues, and lymphatic metastasis is less likely to occur, and therefore aggressive radical surgery can achieve better results.