Literature Review: A Roundup of Important Recent Studies

Study design: Prospective cohort study.

Setting: Tertiary referral center.

Synopsis: Eighty-two adults with unilateral perforations present for six months and longer were enrolled if they also met specific criteria: absence of ossicular or mastoid pathology, nonmarginal location of perforation, normal middle ear mucosa, no evidence of cholesteatoma, no discharge within the previous three months and no major Eustachian tube dysfunction. The edges of the perforation were freshened, and an oversized piece of earlobe fat was placed through the perforation in an hourglass fashion. The overall success rate was 85 percent, but the rate of success significantly decreased when the perforation was greater than 30 percent of the pars tensa.

Bottom line: Dry stable chronic tympanic membrane perforations of 30 percent or less of the pars tensa have a high rate of successful closure with fat graft myringoplasty under local anesthesia in the office setting.

Citation: Konstantinidis I, Malliari H, Tsakiropoulou E, Constantinidis J. Fat myringoplasty outcome analysis with otoendoscopy: who is the suitable patient? Otol Neurotol. 2013;34:95-99.

—Reviewed by Larry Lundy, MD

Molecular Testing May Improve Differentiated Thyroid Cancer Diagnoses

Can molecular testing for gene point mutations and rearrangements be used to diagnose differentiated thyroid cancer more accurately?

Background: Thyroid cancer progresses through a series of genetic and epigenetic changes. Study authors looked for manuscripts featuring BRAF and RAS gene point mutation, RET/PTC chromosomal rearrangements, PAX8/PPARγ chimeric fusion rearrangement and multigene expression (mRNA) tests. BRAF, RET/PTC and PAX8/PPARγ have a high positive predictive value; gene expression microarrays have a high negative predictive value.

Study design: Review of 286 English-language manuscripts with clinical correlates from 2006 to 2012.

Setting: Ovid Medline manuscripts.

Synopsis: The most useful molecular markers available at a commercial level are BRAF and RAS mutations; mRNA testing is also available commercially. The most common clinically useful markers are BRAF and RAS point mutations. BRAF has >99 percent specificity and is rarely found in benign neoplasma. This test has limitations for undetermined lesion diagnosis because many thyroid cancers are negative for the BRAF mutation. Testing for a panel of mutations (BRAF, RAS, RET/PTC) resulted in a 36 percent gain in sensitivity (44 percent to 80 percent). In addition, the authors found that many BRAF+ tumors do not behave aggressively, and BRAF+ PTC tumors generally have a higher rate of central node compartment metastasis. RET/PTC tumors are not commonly aggressive. Negative predictive values from mRNA testing were found for undetermined follicular lesions (95 percent), follicular neoplasm (94 percent) and suspicious cytologic features (85 percent). Microarray testing may also eliminate the need for unnecessary diagnostic lobectomy in 60 percent to 90 percent of cases. The authors found a 10-fold reduction in surgery rates for cytologically indeterminate nodules (74 percent to 7.6 percent) for gene expression classifier benign results. However, performance characteristics of negative predictive value testing require further study.