Synchronous bilateral ureteric metastasis from gastric cancer.

Distant metastasis to the ureters is uncommon. Moreover, isolated ureteric metastasis from gastric cancer is extremely rare and only sporadically reported. It indicates an advanced stage and carrier a very poor prognosis. We describe a case of synchronous bilateral ureteric metastasis from stomach adenocarcinoma after gastrectomy and chemoradiation. To our knowledge, it is the first case published in the literature with such presentation.

INTRODUCTION

Metastasis to the ureter from gastric cancer is rare.[1] Although few, such case reports are mostly from Japanese population while reports from other regions are scarce.[2] We report a patient with bilateral ureteric metastasis diagnosed during the follow-up after subtotal gastrectomy with concurrent chemo-radiotherapy for gastric cancer. Prognosis is poor and palliative treatment by relieving the obstruction together with chemotherapy is advocated.

CASE REPORT

A 40-year-old male patient underwent a subtotal gastrectomy for T3N3M0 poorly differentiated gastric adenocarcinoma, followed by chemo-radiotherapy. He remained disease free and asymptomatic clinically with normal endoscopic and imaging studies. Two years later, upon follow-up he was incidentally found to have bilateral hydronephrosis and hydroureter. Magnetic resonance imaging (MRI) showed enhancing bilateral wall thickening of the lower third of the ureters without any periureteric soft tissue mass [Figure 1]. Retrograde urography and ureteroscopy revealed severe distal ureteric strictures [Figure 2]. The strictured area was biopsied, and a bilateral double J stents were inserted. Histopathology [Figure 3] showed adenocarcinoma infiltrating the smooth muscle resembling gastric adenocarcinoma. Positron emission tomography scan revealed increased activity at both ureteric areas, but there was no other distant positivity. Chemotherapy with Docitaxel and Folifox (5FU, leucovorin, oxaliplatin) was initiated, and the diseases have improved on follow-up.

Figure 1

An axial T2-weighted image showing irregular concentric wall thickening of both lower ureters with minimal periureteric fat stranding

Figure 2

Stricture of the right lower ureter due to metastasis

Figure 3

Metastatic mucin secreting adenocarcinoma in the ureter similar to gastric carcinoma

DISCUSSION

Metastasis of gastric cancer to the ureter is very rare. It can be the first, sole and asymptomatic manifestation of stomach adenocarcinoma dissemination after a period of time.[2] However, the patient may present with loin pain due to hydronephrosis secondary to ureteral obstruction without any symptoms referable to the primary gastric lesion.[34] Most of the published cases of gastric cancer metastasizing to ureter are from Japanese population. Shimoyama reported a similar case in which right nephroureterectomy was performed because of a suspected primary ureteric tumor, but subsequent histopathology confirmed the metastasis from a gastric malignancy.[3]

Presman and Ehrlich described a criterion for true ureteric metastasis, differentiating it from direct invasion by adjacent tissues.[56] Our patient showed a ureteric wall enhancing lesion on MRI scans without periureteric mass indicating the disease was a true ureteric metastasis.

The prognosis of these cases is very poor and there is no report describes an effective surgical or medical therapy for this condition.[7] Chemotherapy including Docitaxel, 5FU and Oxaliplatin could be beneficial, depending on the performance status and the extent of the disease.[2]

CONCLUSION

Although rare, ureteric metastasis can be the first and sole manifestation of gastric cancer dissemination. Ureteric metastasis represents an advanced stage of gastric cancer even if the stomach and other organs appear to be free of the disease.[34] High index of suspicion of such a pathology; in addition to ureteroscopic biopsy will definitely avoid unnecessary nephroureterectomy. The prognosis is poor with very short survival and palliative treatment by drainage of the involved kidneys by an indwelling double J stent together with chemotherapy is advocated.[3]