In many cases, early diagnosis means treatments are more effective, cost less and save more lives. Screening programmes aid early diagnosis and can be used to screen whole populations, such as the fetal anomaly screening given to all pregnant women in the UK, or smaller groups of people with specific risk factors or symptoms, such as bowel cancer screening given to older men and women in the UK. A recent study by Sauter and Butner (2014) suggests that pathological analysis should be performed routinely on all lung tissue resected during surgery to repair a pneumothorax.
The authors identified 94 patients who had lung tissue resected during surgery for spontaneous pneumothorax at Fletcher Allen Health Care, a teaching hospital in Vermont, USA, between 1st January 2002 and 31st December 2012. 22 patients were eliminated from this study as the cause of their lung disease was known. For the remaining 72 cases of primary spontaneous pneumothorax, slides were reviewed for histopathological features, and cross referenced with each patient’s medical records.
61.5% of cases had recurrent episodes of pneumothorax, 96.2% of cases affected the upper lobes of the lung, and all cases had blebs. Six patients (8.3%) showed unexpected clinically significant findings: one patient’s sample revealed the presence of an adenocarcinoma; one patient had cystic lung disease consistent with pulmonary stromal endometriosis (Boyle and McCluggage, 2009); three patients showed lung damage likely to be caused by marijuana use; and one patient had multiple cysts in the lower lobes, and was later diagnosed with BHD.
In the US, routine pathological screening following appendectomy, herniorrhaphy, and cholecystectomy is under debate, with clinically significant findings in 1%, 1.4% and 2% of cases respectively (Lohsiriwat et al., 2009). Thus, Sautner and Butner advocate performing routine screening in lung resections taken following pneumothorax, as their rate of clinically significant findings was much higher at 8.3%.
In in this particular cohort the BHD patient would benefit most from an early diagnosis, as this allows the patient to have kidney surveillance screening, thus reducing their chances of developing advanced kidney cancer. Not only would this obviously be beneficial to the patient, but the authors state that the cost of treating just one case of advanced renal cancer would exceed the costs of screening all 72 samples analysed in this study. Furthermore, diagnosing the individual will also allow family members to get diagnosed, potentially avoiding further cases of advanced kidney cancer.
Further analysis of additional cohorts in different hospitals will be required to determine whether this screening would be truly cost effective. However, this study underscores the important role histopathologists play in diagnosing patients with rare diseases. There are a number of histological clues that suggest a patient has BHD: fibrofolliculomas; choromophobe, oncocytic or hybrid kidney tumours; the presence of intratumoral peripheral small papillary tufts in the kidneys; and small, irregularly-shaped cysts in the basal region of the lung. Thus, teaching histopathologists to recognise these clues and to refer these patients for genetic testing may improve diagnosis rates of BHD.
- Boyle DP, & McCluggage WG (2009). Peritoneal stromal endometriosis: a detailed morphological analysis of a large series of cases of a common and under-recognised form of endometriosis. Journal of clinical pathology, 62 (6), 530-3 PMID: 19155237
- Lohsiriwat V, Vongjirad A, & Lohsiriwat D (2009). Value of routine histopathologic examination of three common surgical specimens: appendix, gallbladder, and hemorrhoid. World journal of surgery, 33 (10), 2189-93 PMID: 19669232
- Sauter JL, & Butnor KJ (2014). Pathological findings in spontaneous pneumothorax specimens: does the incidence of unexpected clinically significant findings justify routine histological examination? Histopathology PMID: 25234592
www.bhdsyndrome.org – the primary online resource for anyone interested in BHD Syndrome.