Journal Thoracic Oncology

Abstracts Journal of Thoracic Oncology • Volume 12 Issue S1 January 2017
United States of America, 7 Pathology, St. Francis Hospital, Memphis/TN/United
States of America, 8 Pathology, Jackson-Madison County General Hospital, Jackson/
TN/United States of America, 9 Pathology, Methodist Healthcare, Memphis/TN/
United States of America, 10 Pathology, Doctors Anatomic Pathology, Jonesboro/AR/
United States of America, 11 Pathology, North Mississippi Medical Center, Tupelo/
MS/United States of America
Background: Incomplete retrieval of intrapulmonary lymph nodes and missed
nodal metastasis are associated with worse-than-expected survival after
(NSCLC) resection. We tested the nodal yield from a novel gross dissection
method. Methods: multi-institutional prospective cohort study of
intrapulmonary (stations 11-14) lymph node yield from lobectomy/greater
NSCLC resection specimens from 11 US hospitals from 2009-2016. A novel gross
dissection protocol was used in 2 hospital pathology departments from June
2012 onwards. Intrapulmonary lymph node yields from all lobectomy or greater
resections before and after the new protocol in the intervention hospitals were
compared to yields from 9 non-intervention hospitals over the same time-span,
using Wilcoxon-Mann-Whitney. From February 2015, some randomly selected
discarded remnant lung specimens in the intervention hospitals were
re-dissected for inadvertently discarded lymph nodes as a quality control
measure. Results: Intrapulmonary lymph node yields in the 2 groups of
hospitals was similar at baseline, followed by a significant increase in the
intervention hospitals with the novel dissection protocol (Table 1).
Subsequently, in 112 specimens re-dissected for independent quality control
after application of the novel dissection protocol, discarded lymph nodes were
found in 30 (27%), down from 90% historically; discarded lymph nodes with
metastasis in 6 (5%), down from 29% historically; and missed N1 nodal
metastasis was found in 1 of 67 (1.5%) pN0 patients, down from 12% historically.
The median number of missed intrapulmonary lymph nodes was 0 (down from 6
historically), the mean (standard deviation) was 0.88 (2.58). The gross
dissection protocol required a median of 15 minutes (range 10 – 24).
Conclusion: A novel gross dissection protocol significantly improves the
thoroughness of intrapulmonary lymph node retrieval and can be successfully
implemented in community-level pathology departments, providing a pathway
for quality improvement in pathologic nodal staging of resected NSCLC.
Keywords: Quality of care, Pathologic staging, lymph nodes, lung cancer
surgery
POSTER SESSION 3 – P3.01: BIOLOGY/PATHOLOGY
MORPHOLOGY –
WEDNESDAY, DECEMBER 7, 2016
P3.01-032 PELP1 EXPRESSION IN MOLECULARLY CLASSIFIED LUNG
ADENOCARCINOMAS
Charuhas Deshpande 1 , Shweta Patel 2 , Jan Silverman 2
1 Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia/
United States of America, 2 Pathology & Laboratory Medicine, Allegheny Health
Network, Pittsburgh/PA/United States of America
Background: Proline-, glutamic acid-, and leucine-rich protein 1 (PELP1) is a
scaffolding protein which functions as a coregulator of several transcription
factors and nuclear receptors. It has a histone-binding domain and plays
essential roles in several pathways including hormonal signaling. PELP1 is a
coregulator of estrogen receptor (ER) and has been shown to be deregulated,
contributing to therapy resistance and is a prognostic biomarker in breast
cancer survival, as well as in other hormone-dependent cancers. Estrogens are
also known to enhance lung tumorigenesis by estrogen receptor pathway 1,
2 . In this study, we investigated the expression of PELP1 in molecularly
classified lung adenocarcinomas, specifically those with known EGFR and
KRAS mutations. Methods: Tissue microarray (TMA) was created using 0.6
mm tissue cores in triplicates from 62 resected lung adenocarcinoma cases
(26 with EGFR mutation and 36 with KRAS mutation). PELP1 antibody (Clone
EPR15212; ABCAM) immunostaining was performed after heat induced epitope
retrieval. Nuclear immunoreactivity for PELP1 was scored for staining intensity
as 0 (negative), 1+ (weak, nucleolar), 2+ (moderate, nucleolar/nuclear) and 3+
(strong nucleolar/nuclear). For statistical analysis, binary split was done as
negative (scores 0 and 1+) and positive (scores 2+ and 3+). These TMAs were
also stained for estrogen receptor (ER) with SP1 rabbit monoclonal antibody
and scored similarly. Results: In our study, 61 cases had evaluable tissue cores
with tumor. Positive PELP1 expression was noted in 14/25 (56%) EGFR mutated
and 30/36 (83%) in KRAS mutated lung adenocarcinomas (p