Lung metastectomy in osteosarcoma: thoracotomy or VATS?

Osteosarcoma, which presents with metastatic lung disease in 15-20% of cases, is one of the few malignancies (along with non-rhabdo soft tissue sarcoma and hepatoblastoma) where resection of metastatic disease to the lung can improve survival.

Although lung metastectomy has been shown to be beneficial in this group, the optimal modality of resection, whether by open thoracotomy or VATS, is not clear. The argument for the use of an open thoracotomy in the management of lung mets has to do with the ability to palpate lesions, whereas VATS relies on imaging for detection of lung nodules. Studies have shown that a CT scan that detects a nodule(s) in the lung can miss additional palpable ones in 50% of patients, approximately half of which contain viable malignant tissue. So, in essence, VATS would likely miss additional malignant nodules, and thus leave behind otherwise palpable malignant lesions, in 25% of patients.

So it seems obvious that an open thoracotomy is the way to go, except that we don’t really know if a VATS followed by close monitoring to detect the 25% of patients with missed nodules that can be salvaged by a second VATS (and thus spare a number of kids a thoracotomy) changes the outcome in terms of long term survival when compared to primary resection of all the palpable nodules with an open thoracotomy.

Reference:
1. St Jude Oncology Review Course
2. Kayton ML et al. Computed tomographic scan of the chest underestimates
the number of metastatic lesions in osteosarcoma (2006);41:200

Why should kids with short gut syndrome be on proton pump inhibitors?

During rounds today, I noticed that someone had changed an order for a proton pump inhibitor to an H2 blocker on one of our patients with short gut syndrome. The reason was some form of shortage, so they decided it was OK to switch.

So it was time for that discussion again.

Patients with intestinal failure secondary to substantial small bowel loss need proton pump inhibitors because they are in a state of hypergastrinemia, as gastrin is primarily metabolized in the small bowel.

Elevated gastrin levels cause an increase in the volume and acidity of gastric secretions, which results in an acidic environment in the small bowel. The increase in volume worsens the fluid and electrolyte balance which is already tenuous in patients with short gut. Additionally, the acidic environment in the small bowel exacerbates malabsorption by causing bile acids to precipitate (sabotage micelle formation) and by inactivating pancreatic enzymes.

He's back on his proton pump inhibitors.

Reference:
Kocoshis SA. Medical management of pediatric intestinal failure. Seminars in Pediatric Surgery (2010);19:20