Abstract :
Introduction: IHC forms an effective supplement to the morphological diagnosis in the emphatic
categorisation of the lung carcinomas, especially the undifferentiated NSCLC i.e NOS types, which is
very essential for an effective therapy. In this regard P63 and TTF-1 are considered the most important
markers in subclassifying the NSCLC. P63 is a sensitive marker for squamous cell carcinoma, and TTF-1
for adenocarcinoma.
Objectives: 1) Immunohistochemical study of guided biopsies of the lung using TTF-1 and p63 markers.
2) To improve diagnostic clarity in poorly differentiated tumours.
Materials and Methods: Forty guided biopsies which were proved malignant on histopathology were
taken from August 2012 to August 2014, at a tertiary health care centre, Bangalore.
Results: Of the total 40 cases, 13 cases (32.5%) were diagnosed as NSCLC NOS because of their
inconclusive morphology on H&E for any particular subtype. Following immunohistochemistry, their
number reduced to 4 (10%), from a massive 13 (32.5%) cases. One case of NSCLC favor SCC was
rediagnosed as NSCLC favor adenocarcinoma, because it was positive for TTF-1 and negative for p63,
and one case of LCNEC being rediagnosed as NSCLC favor adenocarcinoma as it was negative for both
synaptophysin and p63, but positive for TTF-1.
Conclusion: In this study p63 stained 87% of the cases that were suspected to be squamous cell carcinoma
and TTF-1 stained all the 7 cases suspected to be adenocarcinoma on a preliminary H&E report. Further
these two stains were able to categorise the 9 out of the 13 cases of NSCLC NOS effectively into specific
types.
Abbreviations: SCLC - small cell lung carcinoma NSCLC- Non-small cell lung carcinoma; NOS, not
otherwise specified; LCNEC-Large cell neuroendocrine carcinoma IHC: Immunohistochemitry.
Keyword :
NSCLC, Lung carcinoma, P63, TTF1, IHC.