An easily missed lesion!
This lesion was found at gastroscopy
WHAT IS YOUR ENDOSCOPIC DIAGNOSIS?
a) Siewert I SCC
b) Siewert I adenocarcinoma
Lesion isn't centred 1-5cm above the GOJ
c) Siewert II adenocarcinoma
Yes! Lesion staged as T2,N0 on PET-CT
d) Siewert III adenocarcinoma
Lesion isn't centred 2-5cm below the GOJ
This lesion is clearly malignant with a rolled edge and surrounding mucosal ulceration. It was confirmed as a Siewert II adenocarcinoma, T2,N0.
Cancers at this location are becoming more common. They are easy to miss, particularly if you don't slow down as you traverse the gastro-oesophageal junction (GOJ) and/or retrovert at a distance. On retrovertion you need to pull the scope back up so that you can have a close view of the cardia.
Siewert et.al. developed the classification as follows:
Of course it can be difficult to determine where the epicentre of a cancer is, particularly on imaging. At endoscopy you are in a unique position to accurately record the correct Siewert type of the cancer. It makes a difference because the Siewert type has implication for treatment!
Siewert I lesions are treated with oesophagectomy and gastrectomy as these lesions usually metastasise to nodes in the mediastinum. Siewert II are 'true' junctional cancers and mainly metastasise to nodes in the abdominal nodes but in around 15-20% of cases, there are mediastinal nodes. For this reason, patients with Siewert II lesions are only offered gastroectomy (without oesophagectomy) IF there is no mediastinal lymphadenopathy. Arguably, any borderline mediastinal nodes should probably be sampled before or during surgery before a final decision is made not to clear the mediastinal nodes with the resection specimen. Patients with Siewert III cancers are usually offered total gastrectomy plus a distal esophagectomy (to get clear resection margins, a so called R0 resection ) as these lesions spread to peritoneal nodes.