Squamous-cell carcinoma of the lung
Author:
Mikael Häggström [note 1]
Squamous-cell carcinoma (SCC) of the lung:
Contents
Presentations
Microscopic examination
Typical squamous-cell carcinoma cells are large with abundant eosinophilic cytoplasm and large, often vesicular, nuclei.[1]
If uncertain whether it is SCC versus another type of lung tumor, the most useful immunostains are:
p63: Where a positive stain (pictured) indicates SCC rather than lung adenocarcinoma or small-cell carcinoma.[notes 1]
TTF-1: Is almost always negative in squamous-cell carcinoma (as pictured, with positive staining in surrounding type II alveolar pneumocytes). In contrast, TTF-1 is generally positive in lung adenocarcinomas and small-cell carcinomas.[2]
Further workup
Optionally, stain for GATA-3, where a negative tests confirms a primary SCC, whereas a positive finding indicates metastasis from a squamous-cell carcinoma of the skin.[3]
For primary lung non-small cell carcinoma (NSCLC) stages IB - IV (such as being more than 3 cm in size), generally perform full next generation sequencing panel (DNA and RNA) with PDL-1 immunostaining. For an advanced stage NSCLC that is not a candidate for biopsy or re-biopsy, a viable alternative is “liquid biopsy” on peripheral blood for circulating tumor DNA.[4]
Staging
Staging of non-small-cell lung cancers (AJCC, 8th Ed.):[5]
T category | T criteria |
---|---|
TX | Primary tumor cannot be assessed, or tumor proven by the presence of malignant cells in sputum or bronchial washings, but not visualized by imaging or bronchoscopy. |
T0 | No evidence of primary tumor |
Tis | Carcinoma in situ Squamous cell carcinoma in situ (SCIS) Adenocarcinoma in situ (AIS): Adenocarcinoma with pure lepidic pattern, ≤3 cm in greatest dimension |
T1 | Tumor ≤ in greatest dimension, surrounded by lung or visceral pleura, without bronchoscopic invasion more proximal than the lobar bronchus (i.e., not in the main bronchus). |
T1mi | Minimally invasive adenocarcinoma: Adenocarcinoma (≤3 cm in greatest dimension) with a predominantly lepidic pattern and ≤5 mm invasion in greatest dimension. |
T1a | Tumor ≤1 cm in greatest dimension. It also includes a superficial, spreading tumor of any size whose invasive component is limited to the bronchial wall and may extend proximal to the main bronchus (but these are uncommon) |
T1b | Tumor >1 cm but ≤2 cm in greatest dimension |
T1c | Tumor >2 cm but ≤3 cm in greatest dimension |
T2 | Tumor >3 cm but ≤5 cm or having any of the following features:
T2 tumors with these features are classified as T2a if ≤4 cm or if the size cannot be determined and T2b if >4 cm but ≤5 cm. |
T2a | Tumor >3 cm but ≤4 cm in greatest dimension |
T2b | Tumor >4 cm but ≤5 cm in greatest dimension |
T3 | Tumor >5 cm but <7 cm in greatest dimension or directly invading any of the following: Parietal pleura (PL3), chest wall (including superior sulcus tumors), phrenic nerve, parietal pericardium; or separate tumor nodule(s) in the same lobe as the primary. |
T4 | Tumor >7 cm or tumor of any size invading one or more of the following: Diaphragm, mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, or carina. Separate tumor nodule(s) in an ipsilateral lobe different from that of the primary. |
N category | N criteria |
---|---|
NX | Regional lymph nodes cannot be assessed |
N0 | No regional lymph node metastasis |
N1 | Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension. |
N2 | Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s) |
N3 | Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph nodes(s) |
M category | M criteria |
---|---|
M0 | No distant metastasis |
M1 | Distant metastasis |
M1a | Separate tumor nodule(s) in a contralateral lobe; tumor with pleural or pericardial nodes or malignant pleural or pericardial effusion (but note that in a few patients, effusions are negative for tumor in multiple microscopic examinations, and the fluid is non-bloody and is not an exudate, and in such cases the effusion should be excluded as a staging descriptor). |
M1b | Single extrathoracic metastasis in a single organ (including involvement of a single nonregional node) |
M1c | Multiple extrathroracic metastases in a single organ or in multiple organs. |
When T is... | And N is... | And M is... | Then the stage group is... |
---|---|---|---|
TX | N0 | M0 | Occult carcinoma |
Tis | N0 | M0 | 0 |
T1mi | N0 | M0 | 1A1 |
T1a | N0 | M0 | |
T1a | N1 | M0 | IIB |
T1a | N2 | M0 | IIIA |
T1a | N3 | M0 | IIIB |
T1b | N0 | M0 | IA2 |
T1b | N1 | M0 | IIB |
T1b | N2 | M0 | IIIA |
T1b | N3 | M0 | IIIB |
T1c | N0 | M0 | IA3 |
T1c | N1 | M0 | IIB |
T1c | N2 | M0 | IIIa |
T1c | N3 | M0 | IIIB |
T2a | N0 | M0 | IB |
T2a | N1 | M0 | IIB |
T2a | N2 | M0 | IIIA |
T2a | N3 | M0 | IIIB |
T2b | N0 | M0 | IIA |
T2b | N1 | M0 | IIB |
T2b | N2 | M0 | IIIA |
T2b | N3 | M0 | IIIB |
T3 | N0 | M0 | IIB |
T3 | N1 | M0 | IIIA |
T3 | N2 | M0 | IIIB |
T3 | N3 | M0 | IIIC |
T4 | N0 | M0 | IIIA |
T4 | N1 | M0 | IIIA |
T4 | N2 | M0 | IIIB |
T4 | N3 | M0 | IIIC |
Any T | Any N | M1a | IVA |
Any T | Any N | M1b | IVA |
Any T | Any N | M1c | IVB |
Degree of differentiation
(Images show skin SCC, but the same system can optionally be used for lung:[6])
Well-differentiated (and yet invasive) SCC, showing prominent keratinization and may form “pearllike” structures where dermal nests of keratinocytes attempt to mature in a layered fashion. Well-differentiated SCC has slightly enlarged, hyperchromatic nuclei with abundant amounts of cytoplasm. Intercellular bridges will frequently be visible.[7]
Moderately differentiated lesions of invasive SCC show much less organization and maturation with significantly less keratin formation.[7]
Poorly differentiated, where attempts at keratinization are often no longer evident. This is a clear-cell squamous cell carcinoma. The dysplastic cells here infiltrate in cords through the dermis. Poorly differentiated SCC has greatly enlarged, pleomorphic nuclei demonstrating a high degree of atypia and frequent mitoses.[7]
Notes
- ↑ p63 can distinguish SCC from adenocarcinoma with 85% sensitivity, 95% specificity, 94.4% PPV, and 86.4% NPV, and distinguish SCC from small-cell carcinoma with 85% sensitivity, 100% specificity, 100% PPV, and 87% NPV. Reference:
- Jafarian AH, Gharib M, Mohammadian Roshan N, Sherafatnia S, Omidi AA, Bagheri S (2017). "The Diagnostic Value of TTF-1, P63, HMWK, CK7, and CD56 Immunostaining in the Classification of Lung Carcinoma. ". Iran J Pathol 12 (3): 195-201. PMID 29531543. PMC: 5835366. Archived from the original. .
- ↑ For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
Main page
References
- ↑ Dr Nicholas Turnbull, A/Prof Patrick Emanual (2014-05-03). Squamous cell carcinoma pathology. DermNetz.
- ↑ Jafarian AH, Gharib M, Mohammadian Roshan N, Sherafatnia S, Omidi AA, Bagheri S (2017). "The Diagnostic Value of TTF-1, P63, HMWK, CK7, and CD56 Immunostaining in the Classification of Lung Carcinoma. ". Iran J Pathol 12 (3): 195-201. PMID 29531543. PMC: 5835366. Archived from the original. .
- ↑ . Stains & molecular markers - GATA3. PathologyOutlines. Topic Completed: 1 March 2018. Minor changes: 26 June 2020}}
- ↑ . National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology (NCCN Guidelines) - Non-Small Cell Lung Cancer. Version 3.2024. Section: Principles of molecular and biomarker analysis (2024-03-12).
- ↑ Amin, Mahul (2017). AJCC cancer staging manual
(8 ed.). Switzerland: Springer. ISBN 978-3-319-40617-6. OCLC 961218414.
- For access, see the Secrets chapter of Patholines.
- Copyright note: The AJCC, 8th Ed. is published by a company in Switzerland, and the tables presented therein are Public Domain because they consist of tabular information without literary or artistic innovation, and therefore do not fulfil the inclusion criterion of the Swiss Copyright Act (CopA) which applies to "literary and artistic intellectual creations with individual character" (see Federal Act on Copyright and Related Rights (Copyright Act, CopA) of 9 October 1992 (Status as of 1 January 2022)). - ↑ Kadota K, Nitadori J, Woo KM, Sima CS, Finley DJ, Rusch VW (2014). "Comprehensive pathological analyses in lung squamous cell carcinoma: single cell invasion, nuclear diameter, and tumor budding are independent prognostic factors for worse outcomes. ". J Thorac Oncol 9 (8): 1126-39. doi: . PMID 24942260. PMC: 4806792. Archived from the original. .
- ↑ 7.0 7.1 7.2 Yanofsky, Valerie R.; Mercer, Stephen E.; Phelps, Robert G. (2011). "Histopathological Variants of Cutaneous Squamous Cell Carcinoma: A Review
". Journal of Skin Cancer 2011: 1–13. doi: . ISSN 2090-2905..
-"This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."
Image sources