Accurate staging is important because it dictates the management of the disease. Inaccurate staging has been reduced to approximately 20% in T1 – T3, N0, M0 disease using modern staging techniques [2]. Radiotherapy is the treatment of choice for low stage seminoma (IIB or less). High stage of seminoma (above IIB) can have durable periods of remission with cytotoxic chemotherapy [3]. The histological findings in this case were surprising as the clinical tumour stage was initially believed to be T1 or T2, N0, M0, S0 with an extremely good prognosis. Histological involvement of the spermatic cord, however, upstaged the primary tumour to a T3 tumour with positive resection margins. The main factors for prognosis are described in International Germ Cell Consensus Classification. The prognosis according to this staging system is good. Spermatic cord involvement is normally seen within the main cord vasculature or grossly involving the cord. In this case the seminoma cells appeared to be spreading along the spermatic cord by "creeping" along underneath the epithelial lining of the vas deferans. This mode of spread has not previously been described. Following CT scanning the pathological stage was T3, N0, M1 b, S0. This is likely to be a stage IIIc testicular cancer, but does not fit "neatly" within the staging criteria described in the 1997 AJCC staging system. Seminoma spreads most commonly by the lymphatic route alone. The lymphatics that accompany the testicular vessels exit from the testis through the inguinal ring to the retroperitoneal para-aortic lymph nodes and typical patterns of spread occur according to the side of the primary tumour are well recognised [4]. In a study of the microvasculataure of the rat vas deferens by Ohtani and Gannon, [5] the arterial supply and venous drainage has been described in great detail. In rats a sub epithelial capillary network has been identified. It is possible that this capillary network exists in humans. In this case the seminoma may have spread along a similar sub epithelial capillary network. Tumour spread along a speculated sub capillary network has certainly not been previously reported in man. The recognised route of spread of testicular seminoma is via the lymphatics to the para aortic nodes. In this case the pattern of spread did not appear to follow the normal pathway of lymphatic drainage to the para-aortic nodes. It appears to have spread to the mesentery by a direct route below the epithelium of the spermatic cord. This route of metatsatic spread of seminoma has not previously been described in man.
Testicular cancer is curable in the majority of cases. The main factors determining the prognosis are the stage, (including tumour markers), early orchidectomy and early chemotherapy. Patients who develop a germ cell tumour before the age of 50 years have better 10 year relative survival (91%) than those who develop disease after the age of 50 years (84%) [6]. A pre operative CT scan in this case would have helped to stage the tumour more accurately from the outset but would not have altered the management of this patient. The sequence of treatment first before CT scanning is widely accepted and this should be followed in all cases.
The prognosis and period of remission remains uncertain in this case. This case reinforces the need for high spermatic cord ligation and excision at the deep inguinal ring and immediate CT staging. This should be performed even in patients who are thought to have low stage disease and when tumour markers are normal. The histological and radiological findings may be quite unexpected.