Cáceres’ Corner Case 240 – SOLVED

Dear Friends,

Today’s case has been provided by my good friend Victor Pineda. Radiographs belong to a 36-year-old man with cough and fever. For comparison, I am including radiographs taken nine years earlier.


1. Chronic TB changes
2. Endobronchial lesion
3. Congenital lesion
4. None of the above

What do you see? More images will be shown on Wednesday. Come back on Friday to see the answer.

Click here to see the images posted on Monday

Showing coronal and axial CT images. What do you think?

Click here to see the CT images

Click here to see the answer

Findings: Pa radiograph shows a left ill-defined opacity that blurs the upper mediastinal contour (A, arrow) and the lower cardiac border (A, red arrow). In the lateral view there is a retro-sternal line that goes from top to bottom (B, arrows). The appearance is typical of marked LUL collapse, which has not changed in the last nine years. Therefore, the most likely diagnosis is a benign condition that occludes the origin of the LUL bronchus.

Enhanced axial and coronal CTs show marked irregularity of the origin of the LUL bronchus (C, arrow) due to a large mass with coarse calcification (C-D, circles) causing distal lobar collapse. The most likely diagnosis is a benign tumor, either carcinoid or hamartoma. Given the size of the mass and the higher frequency of carcinoid, I would favor this diagnosis. It was proved by biopsy and surgery.

Final diagnosis: endobronchial carcinoid with LUL collapse

Congratulations to Ahmed Al Ani who was the first to suggest the correct diagnosis in the plain film.
Teaching point: Detecting LUL collapse in chest radiographs is important because the great majority are secondary to bronchogenic carcinoma. This patient was lucky.

Dr. Pepe’s Diploma Casebook 156

Dear Friends,

In the aftermath of the Covid-19 scare, I have elected to show a new  “Meet the Examiner” presentation, with questions and answers similar to a real examination. You will get the final answer at the end of the presentation.

Take your time before seeking the answer.

This case starts with PA and lateral chest radiographs of a 63-year-old man with acute chest pain. Would you suspect pulmonary embolism?

3.Need a CT

Click here to see the answer

Findings: the most significant finding is a broad right descending pulmonary artery (A, arrow) with an abrupt cut-off (A, red arrow), a sign of embolus in the artery (Palla sign). Oligemia of the right lung is also visible (Westermark sign). Both signs are suggestive of pulmonary embolism, to be confirmed with enhanced CT.
An enlarged azygos vein is also seen (A, yellow arrow), as well as a bump in the para-aortic line (A, blue arrow)

Click here to see more images

Enhanced CT confirms multiple pulmonary emboli (C, arrows) as well as a large embolus in the right descending pulmonary artery responsible for the Palla sign (D, red arrow)

Caudal slices show a non-enhancing opacity in the lower mediastinum. What would be the most likely diagnosis?

1- Lymphangioma
2- Varices
3- Neurofibromatosis
4- Any of the above

Click here to see the answer

Findings: the serpiginous appearance of the opacity (E-F, red arrows) is compatible with all three diagnosis. Mediastinal varices are the most likely diagnosis because they are not unusual, and the top of the spleen appears to be enlarged (F, asterisk).
The varices are not opacified because the images were taken during the arterial phase.

Late images taken during the venous phase show enhancement of the varices (G, arrow). Coronal reconstruction confirms the splenomegaly and a whorl of varices (H, arrow) responsible for the bump of the para-aortic line in the PA radiograph. The varices (V) drain into an enlarged azygos vein (I, arrow). The increased flow explains the prominent azygos in the PA chest film.
Review of the clinical history discovered that the patient had cirrhosis of the liver.

Final diagnosis: mediastinal varices in a patient with liver cirrhosis and pulmonary embolism

Paraesophageal varices are not uncommon and are secondary to portal hypertension in patients with hepatic cirrhosis. When enlarged, they are visible as a lower middle mediastinal mass in about 8% of chest radiographs of cirrhotic patients.
They may be misdiagnosed in CT studies because they don´t enhance in the arterial phase, as happened in the case presented and in a second case shown below.

Click here to see the second case

58-year-old man with liver cirrhosis. PA radiograph shows widening of lower mediastinal lines, which are slightly undulated (A, arrows). There is increased opacity of the left upper quadrant of the abdomen and the lateral wall of the stomach is indented, suggesting splenomegaly. On the lateral view there is increased opacity of the middle lower mediastinum, with a suggestion of tubular structures (B, circle).

Enhanced axial CT (arterial phase) shows a non-enhancing mass in the middle mediastinum that looks like a cyst (C, arrows). Venous phase demonstrates multiple enhanced veins within the mass (D, arrows). The cirrhotic liver and the enlarged spleen are visible in the coronal CT (E) .

Dr. Pepe’s teaching points:

Remember that the mediastinum is composed mainly of vascular structures. When a mediastinal abnormality is present, always rule out a vascular origin (arterial or venous).

Cáceres’ Corner Case 239 – SOLVED

Dear Friends,

Today’s case has been provided by my good friend Alberto Villanueva. PA radiograph of a 55-year-old male, taken during a workup for rectal carcinoma.


1. Metastasis
2. Pericardial cyst
3. Carcinoma of the lung
4. None of the above

More images will be shown next Wednesday. What do you see?

Click here to see images shown on Monday

Dear Friends,

in my opinion it is difficult to determine in the plain film the origin of large masses adjacent to the mediastinum. I am showing today coronal and axial enhanced CTs.

What do you think?

Click here to see more images

Click here to see the answer

Findings: PA radiograph shows a rounded well-defined mass at the costophrenic angle in the lower left hemithorax (A, arrow). We can infer that the mass is anterior because is displacing the heart towards the right and it does not obliterate the para-aortic line.
In my opinion, when a large mass if adjacent to the midline it is difficult to determine whether it is mediastinal or pulmonary.

Coronal and axial enhanced CT show a solid mediastinal mass with areas of necrosis (B-C, arrows). The most common solid lesion in the cardiophrenic angle are enlarged lymph nodes, which usually are multiple and not very large. In big soft-tissue tumors of this area a thymic origin should be suspected. Although thymic tumors originate in the anterior superior mediastinum, they may slide down along the mediastinal planes and appear at the cardiophrenic angle in the lower mediastinum. Biopsy confirmed the diagnosis of thymoma.

Final diagnosis: mediastinal thymoma

Congratulations to Mohamed Abdulghaffarand MK who were the first to suggest the correct diagnosis

Teaching point: Remember that CT is very helpful in diagnosing cardiophrenic angle masses according to their radiographic density: fat (pericardial fat pad, Morgagni’s hernia); fluid (pericardial cyst) and soft-tissue ( lymphadenopahy and the occasional thymic tumour).

Cáceres Corner Case – Vignette 238

Dear Friends,

Today I am showing a preoperative PA radiograph in a 72-year-old woman.


1. Aortic elongation
2. Aortic dissection
3. Aortic aneurysm
4. Any of the above

What do you see?

Click here to see the answer

Findings: the obvious finding is elongation of the descending aorta. Usually, the diameter of the aorta cannot be determined in the plain film because only the outer wall is outlined by lung air, whereas the medial wall is obscured by the mediastinal structures.

In this case, the tortuous lower aorta projects the medial wall against the lung, allowing to measure the aortic diameter, which is increased (A, red line).
In the other hand, the ascending aorta is not prominent. This a negative finding against aortic elongation, which should involve the whole thoracic aorta.
Therefore, answers 1 and 4 can be excluded. To differentiate between answer 2 and 3 an enhanced CT is needed.

Click here to see more images

Enhanced CT was done. Axial and sagittal images are shown.
What would be your diagnosis?

1. Type B aortic dissection
2. Aneurysm with thrombus
3. Any of the above

Click here to see the answer

Findings: enhanced axial and coronal CT show a normal ascending aorta and a partially thrombosed dilated descending aorta. The fact that the outer wall is calcified (B-C, arrows) indicates that the intima is not displaced and rules out an aortic dissection. The correct diagnosis is aneurysm with partial thrombosis.

Final diagnosis: unsuspected aneurysm of descending aorta

I saw this case three days ago and thought it was a nice demonstration of a negative finding (lack of dilatation of ascending aorta) as mentioned in my last webinar.
As a result of the findings in the plain film, an enhanced CT demonstrated a partially thrombosed aneurysm and the patient was referred for vascular surgery.

This is the last vignette of the season. Since the pandemic is abating, I will resume next week the usual Caceres’ corner cases and Diploma presentations.

Cáceres Corner Case – Vignette 237

Dear Friends,

If you are Sci-Fi fans I recommend this week the novel “The windup girl” and the short stories collection “Pump six” by Paolo Bacigalupi.

Today’s radiographs belong to a 57-year-old woman with cough and fever. She had an osteosarcoma of the lower limb removed eight years earlier.


1. Carcinoma
2. Pneumonia
3. Tuberculosis
4. Any of the above

Click here to see the answer

Findings: PA chest shows haziness of left hemithorax, elevation of the left hilum (A, arrow) and luftsichel (A, red arrow), typical signs of LUL collapse. The collapse is confirmed by the marked displacement of the major fissure on the lateral view (B, arrows). At this point, the best diagnosis is an endobronchial lesion, most likely carcinoma

Click here to see more images

CT with and without contrast enhancement was done. What would be your diagnosis?

1. Carcinoid
2. Carcinoma
3. Endobronchial TB
4. Endobronchial metastasis

Click here to see the answer

Findings: unenhanced CT demonstrates LUL collapse with coarse calcification that seems to follow the path of the bronchus (C, arrows). Enhanced CT shows a non-enhancing endobronchial lesion at the origin of the LUL (D, arrow).

Of the diagnosis offered, the coarse calcification makes carcinoma very unlikely and suggests a carcinoid tumor, although I would expect some enhancement after contrast injection. Given the previous history of osteogenic sarcoma, endobronchial metastases should be considered. I would vote against TB.

Bronchoscopy found a mass occluding the LUL bronchus. Biopsy returned the diagnosis of osteosarcoma.

Final diagnosis: endobronchial metastases from osteogenic sarcoma.

I am showing this unusual case because it is my first and probably my last case of endobronchial metastasis from osteogenic sarcoma. It is also unusual the prolonged span of time (eight years) between the removal of the primary and the appearance of the metastasis.
Remember that the most common cause of LUL collapse is first and foremost a carcinoma of the lung. Endobronchial metastases can give a similar appearance and are more common in tumors of breast, kidney and melanoma although they may occur in any type of tumor, as in the present case.

Dr. Pepe’s Diploma Casebook 155 – SOLVED!

Dear Friends,

Today I am presenting the leading case of a new webinar entitled: “Sherlock Holmes and the curious finding in the chest radiograph”.

AP radiograph belongs to a newborn with respiratory distress.


1. Diaphragmatic hernia
2. Lung tumor
3. Pneumonia
4. None of the above

What do you see? Come back on Wednesday to see the answer and the webinar!

Click here to see the answer

Findings: at a first glance, the predominant abnormality is a large bump in the left hemidiaphragm (A, arrow), suggestive of localized eventration or hernia. However, there is and additional important finding: both humeri are not visible (A, circles).
This baby was born with a congenital absence of the arms (amelia).

I am showing this case to stress the importance of discovering so-called negative findings. Our training emphasizes the discovery of positive findings and forgets teaching us to detect structures that are absent, as this case proves.
My apologies for tricking you, but I was trying to prove my point. You can get more information about negative findings in today´s webinar.

Cáceres Corner Case 236 – Vignette

Dear Friends,

Today’s radiographs belong to a 65-year-old woman with back pain. She was operated for myxoid liposarcoma of the lower limb seven years ago.

Do you see any abnormality?
If so, where is it?

1. Upper area
2. Middle area
3. Lower area
4. I don’t see it

Click here to see the answer

Findings: PA radiograph shows a double contour of the aortic knob (A, arrow) which indicates a superimposed mediastinal mass either in front or behind the knob. Lateral view shows increased opacity of the upper thoracic spine (B, circle), suggesting a posterior mass.

Click here to see more images

Unenhanced CT was done. What would be your diagnosis?

1. Neurogenic tumor
2. Metastasis
3. Neurenteric cyst
4. Any of the above

Click here to see the answer

Findings: coronal and axial unenhanced CT show a posterior mediastinal mass (C-D, arrows). Of the three possible diagnosis, I would choose neurogenic tumor/cyst, because they are frequent in the posterior mediastinum.

Click here to see more images

MRI was done. Would you change your diagnosis?

1. Neurogenic tumor
2. Metastasis
3. Neurenteric cyst
4. Any of the above

Click here to see the answer

Findings: MRI discovers that the vertebral body is affected (E-F, arrows). This makes neurogenic tumor unlikely. There are visible vessels within the mass, which excludes a cyst. Since myxoid liposarcomas metastasize to the spine, the best possibility is metastasis.
At surgery, a metastatic focus from liposarcoma was found.

Final diagnosis: Metastasis from liposarcoma

This is an interesting case because in the PA radiograph the abnormality is partially hidden by the aortic knob and can be difficult to see (remember to use checklists!).

As a chest radiologist occupying the lower strata of the totem pole, I confess my profound ignorance of liposarcomas. Surfing the Internet I have discovered several papers that state that myxoid liposarcoma metastasizes frequently to the spine and that MRI is the method of choice to demonstrate vertebral metastases in these cases.
Now I can transmit my new-found knowledge to you.

Cáceres Corner Case 235 – Vignette

Dear Friends,

Recommendations for this week: two series, Goliath and Fleabag both of them in Amazon. 

Today’s radiographs belong to a 32-year-old man with persistent cough. Non-smoker.


1. Bronchogenic carcinoma
2. Benign endobronchial tumor
3. Endobronchial TB
4. Any of the above

Click here to see the answer

Findings: PA shows a triangular opacity in the right upper lung (A, arrow), suggestive of RUL collapse. The collapsed lobe abuts against the major fissure in the lateral view (B, arrow).
The findings point to an obstructive lesion at the origin of the RUL bronchus. I would say that the most likely diagnosis is carcinoma, despite the age of the patient, because it is a common lesion, but I could not discard the other options. A CT is indicated.

Click here to see more images

Unenhanced CT was done. What would be your diagnosis?

1. Carcinoma
2. Benign endobronchial tumor
3. Tuberculosis
4. None of the above

Click here to know the answer

Findings: coronal reconstruction shows obstruction of the RUL (C, arrow). Unenhanced axial slice shows the collapsed lobe with rounded high-attenuation areas within it (D, circle).

Click here to see more images

Coronal reconstruction shows high-attenuation branching structures within the collapsed lobe which represent mucous impaction (E, circle). Dense mucus at CT is very characteristic of allergic bronchopulmonary aspergillosis (ABPA), which is the most likely diagnosis.
ABPA is accompanied by chronic sinus disease and facial CT shows marked affectation of both maxillary sinuses (F).

Final diagnosis: RUL collapse secondary to mucous plugs in ABPA

After removal of the plugs by bronchoscopy, the chest shows marked improvement.

Allergic bronchopulmonary aspergillosis is caused by hypersensitivity reaction to Aspergillus organisms. Excessive mucus production and abnormal ciliary function lead to mucoid impaction.
Radiologic manifestations include finger-in-glove images in a bronchial distribution They are related to plugging by hyphal masses with distal mucoid impaction. Occasionally, isolated lobar or segmental atelectasis may occur.
In approximately 30% of patients, the impacted mucus has high attenuation at CT

N.B. For those of you who noticed the similarity with case 232 (azygos lobe pneumonia), I should point some subtle but important differences between both cases:

In case 232 the fissure is convex (unusual in collapse). In the present case is straight.
In case 232 the fissure ends before reaching the hilum. In the present case the fissure ends in the hilum.
In case 232 the hilum is of normal size and the RUL artery is visible (arrow). In the present case the hilum is smaller because the RUL artery is included in the collapse.

Cáceres Corner Case 234 – Vignette

Dear Friends,

Today´s radiographs belong to a 48-year-old woman with aortic stenosis.

Most likely diagnosis:

1. Intrathoracic goiter
2. Aortic arch malformation
3. Neurogenic tumor
4. Any of the above

Click here to see the answer

Findings: PA radiograph shows a left mediastinal mass superimposed on the artic knob (A, arrow). The trachea is not displaced. In the lateral view the mass is in the anterior/middle mediastinum (B, arrows).
Regarding the diagnosis offered, the location excludes neurogenic tumor which usually arises in the posterior mediastinum. Intrathoracic goiter is a possibility, but the fact that part of it is the anterior mediastinum and that there is no tracheal displacement goes against this diagnosis. The location of the mass around the aortic knob plus knowing that the patient has aortic valve stenosis point to an aortic arch malformation.

Click here to see more images

Enhanced CT shows that the mass corresponds to a high aortic knob (C, arrow). An oblique view demonstrates the high knob (D, arrow) with a kink and angulation of the aorta representing the lower knob in the PA radiograph (D, red arrow).
My apologies for showing only 3-D images, but the CT was done during the lockdown and they are all I could get.
The patient has no collateral circulation. He had no systemic hypertension and no gradient across the zone of kinking.

Final diagnosis: aortic pseudocoarctation

Pseudocoarctation of the aorta occurs when the aortic arch originates from the 3rd arch, instead of the 4th. In this condition, the aortic arch is higher than usual, with a kinking at the union of the aortic arch and descending aorta, simulating aortic coarctation. Rib notching is absent and systemic hypertension is not present.
This is a rare condition is, but it is not unusual to see it in clinical practice.

To compensate for the lack of CT images in this case, I am showing another pseudocoarctation with similar findings (Fig 1).

Fig 1. PA chest radiograph shows a superior middle mediastinal mass (A, arrow), displacing the trachea. Mass is vaguely seen on the lateral view (B, circle). The most common diagnosis should be an endothoracic goiter but remember that a vascular structure should be always ruled out with enhanced CT.

Coronal CT demonstrates that the mass corresponds to a dilated aortic arch located higher than usual (C, arrow). On the oblique reconstruction, the high aneurysmatic aortic arch is well seen as well as the kinking at the junction with the descending aorta (D, red arrow).
Final diagnosis: aortic pseudocoarctation with aneurysm of the aortic arch.

Cáceres Corner Case 233 – Vignette

Dear Friends,

Recommendations for this week: A history of the world in 100 objects written by Neil McGregor, Director of the British Museum. Series: Good omens (Amazon). 

Today’s radiographs belong to a 51-year-old man with moderate cough.
Do you see any abnormality?
If so, where?

1.  Upper third
2. Middle third
3. Lower third
4. Don’t see it

Click here to see the answer

Findings: PA radiograph shows a left parahilar opacity (A, arrow), seen as an anterior elongated opacity in the lateral view (B, arrow). Its shape in the lateral view suggests mucous impaction.

Click here to see more images

Enhanced CT was done. What would be your diagnosis?

1. Benign endobronchial tumor
2. Allergic aspergillosis
3. Foreign body
4. None of the above

Click here to see the answer

Findings: enhanced axial CT shows an endobronchial obstruction with a distal mucous impaction (C, arrow), also visible in the coronal reconstruction (D, arrow). The clue to the diagnosis lies in recognizing two small lung nodules in the axial view ( C, red arrows) and another one in the right lung in the coronal view (D, red arrow). In addition, there is an enhancing nodule in the gallbladder (D, yellow arrow). These findings suggest widespread malignancy and the correct answer should be 4. None of the above.

Click here to see more images

Bronchoscopy discovered a dark tumor in the lingular bronchus (E), as well as numerous small implants in the trachea, also visible in the CT (F, arrow).
Review of the clinical history discovered that the patient had been operated on for melanoma of the back four years earlier.

Final diagnosis: widespread metastases from melanoma, one of them causing bronchial mucous impaction

Mucous impactions may be multiple or localized. Multiple impactions are related to respiratory diseases that cause bronchiectasis and thick mucus (allergic aspergillosis, cystic fibrosis) whereas localized ones are secondary to segmental endobronchial lesions.

The prevalence of bronchogenic carcinoma makes it the most common cause of localized mucus impaction in clinical practice. Other malignant tumoral lesions are metastases and carcinoids.

Endobronchial metastases represent about 2% of lung metastases. They are usually accompanied by metastatic nodules. They may occur in association with any tumor, but the most common sources are colon, breast, kidney and melanoma.