Periampulary Adenocarcinoma

My father has 2 x 2 cm tumour in periampulary region. The biopsy report says that it is periampulary adenocarcinoma. The CT scan report says that there is evidence of focal soft tissue density mass in the ampulary and periampulary region measuring 2.0x2.0 cm. The mass is focally projecting into to contiguous medial wall of the 2nd part of duodenum with partial intraluminal extension. The adjacent vascular structures are normal. The IVC, aorta, superior mesentric vessels are normal. The portal vein is patent. The gall bladder already resected due to previous cholecystectomy. No lession seen in liver, spleen, pancreas, adrenals and both the kidney. no evidence of upper abdominal lymphadenopathy.

My father is now fit in all resepct after ERCP procedure which release the jeondise symptoms.

Now kindly advise what should I do in this regard? Is there any medication available or we only have option of whipple procedures? Kindly advise.