Omar Salim, 32-year-old male patient from Tanzania presented to us in October 2017 with complaints of a large mass in the abdomen and abdominal pain for 1 year. A previous attempt at surgery in his country had failed in view of the extent of the disease. He was initially evaluated with a CT scan of the abdomen which revealed that there was a large mass in relation to the rectum with compression of the urinary bladder and extending to the anterior abdominal wall upto the level of the umbilicus. There was another large mass in the left lobe of liver occupying nearly the whole of the left upper abdomen. Biopsy revealed a diagnosis of rectal GIST.
Though GISTs are seen fairly commonly in the intestinal tract but only about 5% of all cases of GIST occur in the rectum. The case was discussed in a multidisciplinary team and targeted therapy (imatinib) was given for 3 months. On re-evaluation after 3 months of therapy, it was found that there had been only a slight decrease in the size of the mass but the good thing was that there had been no progression of a disease. There was no evidence of disease spread elsewhere in the body. After detailed discussion with the patient’s family and multidisciplinary team, the patient was planned for surgery. The surgical planning was done to the finest details.
The operating team, led by Dr Vivek Mangla (Consultant Gastrointestinal and Hepatobiliary Surgeon) at Sir Ganga Ram Hospital, New Delhi, comprised of Dr Manu Gupta (Consultant Urology), Dr Akhil Kumar (Consultant, Anaesthesia), three assistant surgeons and other supporting staff. Patient underwent resection of both the lesions successfully on January 31, 2018. The surgery lasted 7 hours and despite the extent of a tumour and surgery, and did not require any blood transfusion during the surgery. A liver tumour was 15×14 cm in size and weighed 1.2 kg. The rectal tumour was 24 x 13 cm in size and weighed 1.9 kg. The patient subsequently recovered uneventfully and has been discharged from the hospital.
Dr Vivek Mangla, who has a keen interest in GI and HPB cancer surgery, told that there were many challenges in the case. Firstly, this patient had two large tumours, one in the liver requiring a major liver resection, and the other in the rectum (distal-most part of large intestine) and surgery for complete removal of both these tumours was deemed the best treatment option in the given situation. However, this entailed extensive surgery (removing a part of the liver bearing the tumour and removal of the large rectal tumour) and need for a surgical team with expertise in handling tumours and cancers of both the liver and large intestine.
It was decided to first remove the liver lesion to create some working space in the abdomen to facilitate the more complex part of removal of the rectal mass which was bigger and located in a more difficult to access location. Secondly, tumours in most of the cases of rectal GIST reported previously were smaller than 5 cm in size while the size of the tumour in this patient was nearly five times of that. The management of large tumours of the rectum is particularly challenging. These tumours tend to be very vascular and surgery for these entails the risk of major blood loss. There was very limited working space as most of the space was occupied by the tumour.
Presence of vital structures in the area including the urinary bladder and ureters, and nerves supplying the muscles which work to ensure proper urinary function increases the complexity of the operation. Another challenge was that the tumour was quite close to the muscles which help in maintaining continence (i.e. ability to control the passage of stools) and it required very careful surgery to ensure that the tumour was removed completely but at the same time, the muscles required to maintain continence to stools could be preserved with a special technique more often used in treatment of distal rectal cancer (called intersphincteric resection). To the best of our knowledge, this is the first report of a synchronous resection for such a large rectal GIST with a solitary large liver lesion.