Medical Image of the Week: Bronchopleural Fistula

Figure 1. The blue arrow indicates a fistulous communication between bronchus and the pleura.

Figure 2. Red arrow indicates radiotracer trapping in the pleural space and adjacent right anterior lower lung field.

A 58-year-old man with past medical history significant for chronic smoking and seizures was referred to the emergency room after a chest x-ray done by his primary care physician for evaluation of cough showed a hydropneumothorax. His symptoms included dry cough for past 2 months without fever, chills or other associated symptoms. He did not have any thoracic procedures performed and had no past history of recurrent infections. He was hemodynamically stable. Physical examination was only significant with decreased breath sounds on the right side of the chest.

Thoracic CT with contrast was performed which showed complete collapse of the right lower lobe, near complete collapse of right middle lobe as well as an air-fluid level. There was a suspicion of a direct communication between bronchi and pleural space at the posterior lateral margin of the collapsed right lower lobe (Figure 1). The presence of bronchopleural fistula (BPF) was confirmed with the help of lung scintigraphy, which showed trapping of radiotracer in the right lung at a location consistent with the chest CT findings of BPF (Figure 2). The patient was admitted and extensive infectious work up was negative. Biopsy of the right pleura was negative for malignancy. He underwent video-assisted thoracoscopic surgery (VATS) decortication of his right lung and was stable on subsequent follow up with complete resolution of his cough.

BPF has mortality rate between 18 to 67% (1). CT of the chest can occasionally demonstrate a direct fistulous communication, as seen in our case.  However, Westcott and Volpe (2) have shown sensitivity of CT chest to be 50%. Other useful noninvasive imaging techniques include lung scintigraphy. In this modality, the fistula is identified by seeing a trapping of radioisotope labeled gas as there is no mechanism for a clearance of gas after its diffusion into the pleural space.  Raja et al. (3) demonstrated that lung scintigraphy had 83% sensitivity and 100% specificity in diagnosing BPF.  

As seen in this case lung nuclear scintigraphy offers a cheaper, more sensitive, and less invasive approach to diagnosis of BPF.

Hem Desai MD, MPH and Anthony Witten DO

Department of Internal Medicine

University of Arizona

Tucson, AZ USA

References

1. Hollaus PH, Lax F, el-Nashef BB, Hauck HH, Lucciarini P, Pridun NS. Natural history of bronchopleural fistula after pneumonectomy: a review of 96 cases. Ann Thorac Surg. 1997 May;63(5):1391-6; discussion 1396-7. [CrossRef] [PubMed]
2. Westcott JL, Volpe JP. Peripheral bronchopleural fistula: CT evaluation in 20 patients with pneumonia, empyema, or postoperative air leak. Radiology. 1995 Jul;196(1):175-81. [CrossRef] [PubMed]
3. Raja S, Rice TW, Neumann DR, Saha GB, Khandekar S, MacIntyre WJ, Go RT. Scintigraphic detection of post-pneumonectomy bronchopleural fistulae. Eur J Nucl Med. 1999 Mar;26(3):215-9. [CrossRef] [PubMed] 

Cite as: Desai H, Witten A. Medical image of the week: bronchopleural fistula. Southwest J Pulm Crit Care. 2016;13(3)150-1. doi: http://dx.doi.org/10.13175/swjpcc069-16 PDF

Medical Image of the Week: Renal Cell Carcinoma Metastasis

Figure 1. Panel A: Axial CT image noncontrast showing small pulmonary nodules concerning for metastasis. Panel B: Axial CT image depicting 15 cm mass, originating from the right acetabulum and adjacent iliac bone. Panel C: Coronal CT image showing prominent left renal cyst measuring almost 40 mm. Panel D: Coronal CT image displaying femoral head intact but surrounded by abnormal soft tissue, concerning for neoplasm. There is bony destruction and lytic process in the anterior and posterior pillars of the right acetabulum.

A 65-year-old man was complaining of progressive weakness and right knee pain with limping since November 2014 was admitted recently to a local hospital and treated for chronic kidney disease related anemia, Klebsiella urinary tract infection and methicillin-sensitive Staphylococcus aureus wound infections. He was discharged to rehab, but continued to have progressive weakness, pain and limping. He was sent to our hospital for further evaluation and imaging.

CT of the abdomen and pelvis non contrast, due to decreased glomerular filtration rate, revealed a 15 cm mass originating from the right acetabulum and adjacent iliac bone with bony destruction and lytic processes (Figure 1). The femoral head is also surrounded by abnormal soft tissue (Figure 1D). There were also small pulmonary nodules (Figure 1A), small lymph nodes in the transverse mesocolon and retroperitoneum, and an enlarged left adrenal gland concerning for other metastasis.

CT guided biopsy of the lesion revealed a neoplastic process composed of atypical cells with centrally placed nuclei, abundant clear cytoplasm arranged in a vascular network. Immunohistochemical stains demonstrated positivity for the following: vimentin, low molecular weight keratin, CD10, RCCA, and PAX-8. These findings are consistent with metastatic renal cell carcinoma.

A total body bone scan with Tc-99m methylene diphosphonate, performed to locate other osseous metastasis, was negative for distant metastasis other than the large destructive lesion destroying the right ileum previously noted on CT.

Renal cell carcinoma (RCC) is a cortical tumor with malignant cells originating from the epithelial lining of the proximal tubules. Renal cancer is amongst the 10 most common cancers in both men and women, with RCC accounting for about 80% of the total incidence and mortality (1). RCC has been referred to as “the internist’s tumor” as it can cause systemic symptoms unrelated to the renal cancer. The classic triad of RCC (flank pain, hematuria, and a palpable abdominal renal mass) occurs in at most 9 percent of patients (1). Most cases of RCC are diagnosed incidentally on radiographic investigation done for other reasons. Unfortunately, many patients are asymptomatic until the disease is advanced. At presentation, approximately 25% of individuals either have distant metastases or advanced local disease (2). Biopsy is not usually required to diagnose RCC. Contrast-enhanced CT can be used to diagnosis and stage RCC. 

Stage IV disease has a median survival of about 12 months with systemic cytokine therapy and 28 months with targeted therapies, based on analyses from the International Metastatic RCC Database Consortium (IMDC) (1,3).

Erin Yen MS¹, Benjamin Rayikanti MD², Yunuen Valenzuela MD³, Jennifer Segar MD³

¹ Midwestern University Arizona College of Osteopathic Medicine, Phoenix

² Tucson Hospitals Medical Education Program

³ Department of Internal Medicine, Banner University Medical Center Tucson

Tucson AZ USA

References

1. American Cancer Society. Cancer Facts & Figures 2016. Atlanta, GA: American Cancer Society; 2016. Available at: http://www.cancer.org/research/cancerfactsstatistics/cancerfactsfigures2016/ (accessed 9/14/16).
2. DeKernion JB. Real numbers. In: Campbell's Urology, Walsh PC, Gittes RF, Perlmutter AD (Eds), WB Saunders, Philadelphia 1986. p.1294.
3. Heng DY, Choueiri TK, Rini BI, et al. Outcomes of patients with metastatic renal cell carcinoma that do not meet eligibility criteria for clinical trials. Ann Oncol. 2014 Jan;25(1):149-54. [CrossRef] [PubMed]

Cite as: Yen E, Rayikanti B, Valenzuela Y, Segar J. Medical image of the week: renal cell carcinoma metastasis. Southwest J Pulm Crit Care. 2016;13(3):135-6. doi: http://dx.doi.org/10.13175/swjpcc068-16 PDF