There are multiple findings of metastatic disease, including lung metastases, liver metastases (blue arrow), left adrenal metastasis, and soft tissue metastases (green arrow; characteristic of melanoma). There are questionable findings of diverticulitis.
One of the misses in this case is a moderate to large amount of pneumoperitoneum, which is better seen using lung windows. In the image below, there is free air in the anterior abdomen, region of the ligamentum venosum, and left upper quadrant adjacent to the stomach (red arrows).
There is another potential miss in the left pelvis, as illustrated by the yellow arrow in the image below - left common femoral vein thrombus. I say potential because there is mixing in the right common femoral vein that looks similar and the patient did not get a follow-up doppler ultrasound to confirm left CFV DVT.
There is one main reason these findings were missed by the interpreting radiologist: he didn't look for them! Your search pattern must include a 1) dedicated search for free air using lung windows and 2) evaluation for venous thrombosis from the top slice to the bottom slice.
When I look for free air, I make one pass looking at the anterior abdominal cavity followed by a second pass looking at the middle abdominal cavity. I have cases of missed pneumoperitoneum that is only seen in the porta hepatis related to a perforated duodenal ulcer, so don't always expect free air to be in the anterior abdominal cavity. You have to use lung windows because sometimes CT scanners reconstruct images such that fat is very dark gray and foci of pneumoperitoneum can blend into mesenteric/omental fat and be missed.
This patient is at particular risk for DVT (and incidental PE) because they have metastatic disease. Regardless, your search pattern should include the veins in every study. The possible left CFV DVT is a good example of an edge of the film miss - it is only seen on the bottom few slices.
The last point for this case is that it is a good example of satisfaction of search error. When discussing the case with the radiologist who interpreted this study, they said they had been so caught up with the metastatic disease and diverticulitis that they simply forgot to look for free air. The indication was abdominal pain and findings of diverticulitis accounts for the patients symptom, thereby causing a premature termination of the search for other causes. In this case, the patient came back a few days later septic with infarcted bowel. She was placed on palliative care due to the advanced melanoma and passed away shortly afterwards.
