Tuesday, February 9, 2016


I posted:  An 11 yo girl fell, striking her coccyx. With persistent discomfort, she was referred for orthopedics evaluation.  A longstanding history of low back pain was elicited.  A complete spine MRI was obtained. There was a small syrinx from approximately T3 through the T10-T11 levels reaching a maximum transverse diameter of approximately 1.7 mm at the T7 level. The spine MRI was windowed such that a portion of the posterior fossa was viewed, including the lower portion of the fourth ventricle.  It was evident that a mass filled the fourth ventricle. This partially enhancing mass exerted mild mass effect on the dorsal pons, and measured approximately 4.4 x 3.0 x 2.8 cm. On further questioning, she had been complaining of headaches, as well as dizziness when she changed positions, for the last couple of months. The tumor was a juvenile pilocytic astrocytoma.
A reply:   Yes, a bit of serendipity to be sure.  Maybe we should note, though, without taking anything away from the clinician(s) in the instant case, that the 3 princes of Serendip did this sort of thing without the aid of MRIs or other such technologies.
Another reply:  The issue of serendipity has become a significant one in genetics, due to the frequent incidental findings of genetic variants when analyzing a genome.  A committee of the American College of Genetics and Genomics issued a report that wrestled with the issue of when to disclose such incidental findings: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3727274/ 
We have of course dealt with incidental findings for years.  During my residency in the 1980s I evaluated a child in the Emergency Room after he fell off his bicycle and hit his head.  A skull X-ray showed no fracture, but showed an abnormal smooth density in the middle of the head.  A CT scan demonstrated that this was a tooth with nearby embryonal-type material.  We never considered whether or not to disclose to the family that this appeared to be a teratoma - we just assumed that we were required to disclose the information.  We brought in the neurosurgeons to discuss whether to intervene and the entire family left immediately after talking to the neurosurgeons.  As far as I know they were lost to follow-up.   
As people discuss whether to disclose genomic incidental findings, I am reminded that before genomic analysis, we dealt with the issue of incidental findings with radiological tests.  It seemed obvious to us that we needed to disclose such incidental findings, but in the example I recounted, it is not clear how much we helped the family. 
For genomic analysis my inclination is to give the family choices in advance about what incidental findings to receive, but many families are not in any position to make such choices in an informed way and there is definitely a role for a default approach such as that in the ACMG report.  For radiology, it seems that the default is to disclose anything of significance.
I added:  15 mo female with torticollis and gait abnormality.  There had also been observation of intermittent anisocoria.  There was a rightward head tilt.  At examination, pupils were equal but more briskly reactive on the right.  There was a broad-based, stooped gait. MRI of the head and cervical spine had been normal.  An MRI of the spine was obtained.  The spine was normal, but there was a suprarenal tumor present.  This was a neuroblastoma. Eventually, it was the cause of the patient's demise.

No comments:

Post a Comment