Laparotomy site implantation metastasis of carcinoma of the papilla of Vater

Introduction

Carcinomas of the papilla of Vater are a heterogeneous group of tumours arising from the meeting point of different epithelia including those from bile duct, pancreatic duct and duodenal mucosa. Although similar in presentation, the prognosis of these tumours differs owing to diverse local spread and metastasising patterns, reflecting this heterogeneity. ¹ Regional lymph nodes, liver and lungs are the primary metastatic. We present a patient with abdominal wall incision-site metastasis of a low-grade mixed-type adenocarcinoma of the papilla of Vater one year after pylorus-preserving pancreaticoduodenectomy (PPPD).

Case report

A 57-year-old male patient presented to our department with a painless oval 7 cm swelling in the medial part of his extended right subcostal laparotomy scar. On palpation, the tumour was firm, non-tender, moderately mobile and seemed not to adhere to, or infiltrate, viscera. He had noticed the tumour two months before admission when it was smaller. Eleven months earlier, he had received R0 PPPD for a 1.5 cm low-grade, mixed-type adenocarcinoma of the papilla of Vater with duodenal wall involvement, but without lymphovascular/perineural invasion, regional lymph node involvement or distant metastases. It was staged 1B (T2N0M0). At the time of surgery, CA19-9 level was 117 U/mL (normal range: 0–37 U/mL). He had not received any adjuvant chemotherapy or radiotherapy. During the current admission, chest X-ray and laboratory results including CA19-9 serum level were within normal range (20 U/mL). Computed tomography scan confirmed a solid, well-defined mass, 6 cm in its largest diameter, in the right subcostal part of the abdominal wall within the incision scar (Figure 1). There were no signs of intraabdominal local recurrence, visceral involvement or distant metastases. At surgery, the tumour was completey excised. Histopathology revealed its metastatic origin from a pancreaticobiliary adenocarcinoma (Figure 2). The postoperative course was uneventful. Data collection and presentation were approved by the hospital Ethics Committee (Decision No: 14042) and patient's informed consent was obtained. OPEN IN VIEWER

OPEN IN VIEWER

Figure 2.

(a) Infiltrative adenocarcinoma of the papilla of Vater (hematoxylin/eosin × 100); (b) neoplastic glands with desmoplastic stroma in deep dermis (hematoxylin/eosin × 100).

Discussion

Ampullary carcinomas (AC) arise from the ampulla of Vater and account for 0.2% of all gastrointestinal and 7–9% of periampullary malignancies. ² In comparison to other periampullary carcinomas (pancreatic, distal bile duct and duodenal), ACs have a better prognosis owing to a higher resection rate and lower recurrence rate. ³ This may be the result of an adenoma to adenocarcinoma carcinogenesis pattern. ⁴ There is less of a tendency to lymphatic and vascular invasion applicable to these tumours. Also, ACs are further notable for their varied histomorphologic features, reflecting the heterogeneity of their origin and significantly influencing tumour biology and patient prognosis. Hence, further subdivision of ACs based on their exact histology is suggested since histologic subtype is the most important prognostic marker necessary for tailored patient management. ¹ The most common are pancreaticobiliary and intestinal histological subtypes, with the latter having more favourable prognosis. ⁵ Other less common types include mixed, mucinous, signet-ring cell, clear cell, neuroendocrine, poorly differentiated, undifferentiated and invasive papillary variants.

Tumour size, invasion depth, histological (sub)type and stage, lymph node status, perineural and lymphovascular invasion, resection margin and CA19-9 level higher than 37 U/L are the most important prognostic predictors in patients with localised disease.^2,3,5,6 Regional lymph nodes, liver and lungs are the most common sites affected by AC metastases. Although reported, other metastatic sites are extremely rare. ⁷ Our patient developed a solitary metastatic deposit in the abdominal wall incision site. While port site recurrence, i.e. abdominal wall metastasis at the instrument placement sites after laparoscopic Whipple’s procedure for moderately differentiated pancreatic head ductal adenocarcinoma (T3N1M0) has been reported, ⁸ implantation laparotomy site metastasis from low-grade AC after open PPPD is unusual and has not been previously reported. At the time of the first operation, no gross tumour spillage was noted and the specimen was retrieved from the abdomen via a wide abdominal incision. The curiosity of this disease progression is further emphasised by the absence of poor prognostic predictors except for the high CA19-9 level at the time of the first surgery and perhaps a dominant, more aggressive, pancreaticobiliary histological component to the tumour.

Conclusion

The possibility of implantation metastasis of AC must be kept in mind. Complete surgical removal seemed a reasonable treatment in this situation. Although only advocated for resected ACs with more unfavourable prognostic features (tumour larger than 2 cm, positive lymph nodes, positive resection margins, perineural and lymphovascular invasion), we suggest adjuvant chemoradiation therapy might be considered also for patients with low-grade localised disease as a potentially preventative measure against any, including this unusual, metastatic progression with normal CA19-9.