Table 4.

Reassessment of 16 EGFR/KRAS-mutant SQCCs identified by routine clinical genotyping

Pt IDAge genderPack-yearsPathologyMutationInterpretation
Sample noa; site (time in mo)Specimen typeDiagnosis (original → Δ post-reviewb)IHC
TTF-1ΔNp63
161M0(i) Spine (0)BxSQCCndndEGFR ex 19 18 bp Δ“SQCC” = component of AD-SQC
(ii) Lung (−26)BxSQCC → AD-SQCndndEGFR ex 19 18 bp Δ
271F0(i) Lung, RLL (0)BxSQCC+EGFR ex 19 15 bp Δ“SQCC” = component of AD-SQC
(ii) Lung, RLL (−23)BxADC+ndEGFR ex 19 15 bp Δ
358F0(i) Bronchus (0)BxSQCC+EGFR ex 19 15 bp Δ“SQCC” = component of AD-SQC
(ii) Lung, RUL (−9)BxAD-SQCndndEGFR ex 19 15 bp Δ
(iii) Lung, LLL (+21)BxADC+EGFR ex 19 15 bp Δ
445F0(i) Sacrum (0)FNASQCC+EGFR ex 19 15 bp Δ“SQCC” = component of AD-SQC
(ii) Lung (−17)Pleural fluidADC+EGFR ex 19 15 bp Δ
546M0(i) Lung (0)FNASQCC+EGFR ex 19 9 bp Δ“SQCC” = component of AD-SQC
(ii) SCLN (+1)BxADC+EGFR ex 19 9 bp Δ
673M25(i) Adrenal (0)ResectionSQCC+EGFR ex 19 18 bp Δ“SQCC” = component of AD-SQC
(ii) SCLN (−9)BxAD-SQCfcfcnd
768M45(i) Lung (0)LobectomySQCC+EGFR ex 19 15 bp Δ“SQCC” = component of AD-SQC
(ii) Hilar LN (0)DissectionADC+EGFR ex 19 15 bp Δ
850M63(i) Skin (0)FNASQCCndndKRAS G12C“SQCC” = component of AD-SQC
(ii) Lung (−5)FNAADCndndnd
(iii) SCLN (−5)BxSQCC → AD-SQCfcKRAS G12C
963F0(i) Lung, LUL (0)BxSQCC+KRAS G12D“SQCC” = component of AD-SQC
(ii) Lung, LUL (0)FNAADCndndnd
(iii) Lung, LUL (+5)LobectomyAD-SQCfcfcKRAS G12D
1058M0(i) Bronchus (0)BxSQCC+EGFR L858RIndeterminate
(ii) Spine (+1)BxSQCC+nd
1189F0LungBxSQCC → ADC+EGFR L858R“SQCC” = PD ADC
1253F31LungLobectomySQCC → ADC+EGFR ex 19 18 bp Δ“SQCC” = PD ADC
1349F33BronchusBxSQCC → ADC+KRAS G12V“SQCC” = PD ADC
1469F34Hilar LNFNASQCC → ADC+KRAS G12V“SQCC” = PD ADC
1563M80BoneBxSQCC → favor ADCKRAS G12S“SQCC” = favor PD ADC
1658M51LungBronchial excisionSQCC with 5% glandsf (5%)cf (95%)cKRAS G12C“SQCC” = biphasic tumor with <10% glands

Abbreviations: +, diffusely positive; −, negative; Δ, deletion or change; ADC, adenocarcinoma; Bx, biopsy; ex, exon; f, focally positive; FNA, fine-needle aspiration; LLL, left lower lobe; LN, lymph node; LUL, left upper lobe; nd, not done (tissue insufficient or unavailable); PD, poorly differentiated; Pt, patient; RLL, right lower lobe; SCLN, supraclavicular lymph node.

  • aSample order is nonchronologic: sample 1 represents an index case (EGFR/KRAS-mutant “SQCC”).

  • bReview diagnosis was based on a combination of morphology and IHC; in the absence of IHC, tumor type was considered verified if morphology was diagnostic.

  • cTTF-1- and ΔNp63-labeled distinct cell populations.