From the Guidelines
Laboratory investigations are not routinely needed for superficial squamous cell carcinoma (SCC) of the skin, as the diagnosis is typically made clinically and confirmed with a skin biopsy. For most cases of superficial SCC, no specific blood tests or other laboratory investigations are recommended as part of the standard workup, according to the guidelines of care for the management of cutaneous squamous cell carcinoma 1. Management typically involves complete surgical excision with appropriate margins, which is usually curative for superficial lesions.
In certain circumstances, such as in immunocompromised patients or those with extensive or aggressive disease, imaging studies might be considered to evaluate for potential metastasis, but this is not common for superficial variants, as stated in the guidelines 1. The lack of recommended laboratory testing reflects the fact that superficial SCC is primarily a local disease that rarely metastasizes when detected and treated early. If there are concerns about more advanced disease, regional lymph node involvement, or distant metastasis, then further investigations including imaging studies would be warranted, but specific laboratory tests would still not be the primary diagnostic tools.
Some key points to consider in the management of superficial SCC include:
- The use of a staging system, such as the Brigham and Women’s Hospital (BWH) system, to classify tumor categories based on clinical and pathologic risk factors 1
- The role of imaging studies, such as computed tomography or ultrasound, in evaluating for nodal metastasis or deep structural involvement in high-risk tumors 1
- The potential use of sentinel lymph node biopsy (SLNB) in high-risk patients, although its value in cSCC is currently unknown 1
- The importance of a thorough clinical examination of the regional lymph node basins in all patients with cSCC 1
From the Research
Lab Investigations for Superficial Squamous Cell Carcinoma
- There is no clear evidence to suggest that lab investigations are necessary for the diagnosis of superficial squamous cell carcinoma 2, 3.
- The diagnosis of superficial squamous cell carcinoma is typically made through histopathology and correct surgical excision 2.
- Initial tissue sampling for diagnosis is usually done through a shave technique or a punch biopsy of the most abnormal-appearing area of skin 3.
Recommended Labs
- There are no specific lab tests recommended for the diagnosis of superficial squamous cell carcinoma 2, 3, 4, 5.
- The focus is on diagnostic imaging techniques such as dermoscopy and reflectance confocal microscopy to increase diagnostic accuracy 2, 5.
- High-frequency ultrasonography, optical coherence tomography, and computed tomography may also be used as diagnostic methods 5.
Treatment and Follow-up
- Treatment options for superficial squamous cell carcinoma include topical therapy, cryosurgery, photodynamic therapy, and radiation 4, 5.
- Surgical treatment methods include surgical excision with margins and Mohs surgery 3, 5.
- Monitoring for recurrence is important, as the five-year risk of subsequent skin cancer is 41% after an index keratinocyte carcinoma 3.