Cutaneous Squamous Cell Carcinoma Guidelines

Updated: Sep 24, 2021
  • Author: Jeffery W Wells, MD; Chief Editor: Arlen D Meyers, MD, MBA  more...
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Guidelines Summary

American College of Radiology

Appropriateness Criteria® for the treatment of aggressive nonmelanomatous skin cancer of the head and neck, issued by the American College of Radiology (ACR) in 2014, include the following recommendations [78] :

  • Cutaneous squamous cell cancer (cSCC) that is resected with negative margins and does not display high-risk features can be safely observed postoperatively
  • Consider adjuvant radiotherapy for resected SCC that demonstrates perineural invasion, especially multifocal; in cases of extensive perineural invasion or invasion of named nerves, the nerve should be targeted with radiotherapy back to the skull base
  • Patients with periparotid nodal disease should be managed by surgical resection with neck dissection, followed by adjuvant radiotherapy
  • Concurrent cisplatin-based chemotherapy can be considered in patients with high-risk pathologic features (eg, margin positivity or extracapsular extension) or in patients with unresectable, locally advanced disease
  • Intensified adjuvant therapies, such as radiotherapy for intermediate-risk patients and incorporating systemic therapies concurrently with radiotherapy, may benefit certain classes of patients

Scottish Intercollegiate Guidelines Network

Recommendations from the Scottish Intercollegiate Guidelines Network's (SIGN's) updated guidelines for the management of primary cutaneous squamous cell carcinoma (cSCC), published in 2014, are summarized below. [79]  

The following are considered high-risk clinical features [79] :

  • Immunosuppression
  • Ear as the tumor site
  • Horizontal tumor diameter of >20 mm 
  • Tumor depth >4 mm; >6 mm indicates a very–high-risk tumor
  • Tumor extension beyond the dermis into or through subcutaneous fat 
  • Perineural invasion
  • Desmoplastic subtype 
  • Poorly differentiated tumor status 

The presence of any of the above high-risk features in a patient with primary SCC warrants discussion of the patient in a multidisciplinary team (MDT) meeting.

SCC treatment options include the following [79] :

  • Surgical excision for high-risk tumors - A clinical peripheral margin of 6 mm or greater is indicated when surgically achievable and clinically appropriate
  • Surgical excision for low-risk tumors - A clinical peripheral margin of 4 mm or greater is indicated when surgically achievable and clinically appropriate
  • Mohs micrographic surgery should be considered for selected patients with high-risk tumors when tissue preservation or margin control is challenging, as well as for patients with any tumor at a critical anatomic site
  • Consider curettage and cautery for patients with low-risk tumors if healthcare professionals have had appropriate training with a blunt curette
  • Photodynamic therapy should not be used for treatment of primary SSC
  • Consider primary radiotherapy for patients if surgical excision would be extremely challenging or difficult to perform or would be likely to result in an unacceptable functional or aesthetic outcome
  • Consider adjuvant radiotherapy for patients with a high risk of local recurrence or with close or involved margins when further surgery carries an increased risk of complications, including functional or aesthetic morbidity

For patients with SCC with any high-risk features, posttreatment follow-up appointments every 3-6 months for 24 months should be offered. Depending on the clinical risk, it may be appropriate to also schedule one 3-year follow-up appointment. [79]

Dermatological Cooperative Oncology Group

Guidelines on cutaneous squamous cell carcinoma (cSCC) from the Dermatological Cooperative Oncology Group of the German Cancer Society and the German Society of Dermatology were published in April 2020. They include the following. [80]

Because data are insufficient regarding the value of regional lymphadenectomy following positive sentinel lymph node biopsy (SLNB), do not perform prophylactic lymphadenectomy.

When lymph node metastasis is clinically manifested, the patient should undergo regional (therapeutic) lymphadenectomy.

When local disease is inoperable or not completely resectable, radiation therapy should be performed.

The following cases should prompt use of postoperative radiation therapy:

  • R1 or R2 resection (if reexcision is not feasible)
  • Extensive lymph node involvement (>1 affected lymph node, lymph node metastasis >3 cm, capsular penetration)
  • Intraparotid lymph node involvement

Existence of the following risk factors should prompt treatment with adjuvant radiation therapy:

  • Surgical margins < 2 mm and reexcision is not feasible
  • Extensive perineural infiltration

Employ micrographically controlled surgery (MCS) for the treatment of local or locoregional recurrence.

If, over the course of the resection, residual, unresectable tumor tissue (R1 or R2 resection) is in evidence, the affected area should undergo radiation therapy.

If an interdisciplinary tumor board determines inoperability, radiation therapy should be performed.

British Association of Dermatologists

Guidelines on the management of cutaneous squamous cell carcinoma (cSCC) were published in March 2021 by the British Association of Dermatologists. [81]

Pretreatment for cSCC

If there is any diagnostic uncertainty, histologic confirmation of cSCC lesions should be obtained before planning definitive treatment.

Before performing any diagnostic or treatment procedure, the following should be recorded:

  • Maximum clinical cSCC lesion dimension (typically diameter, in mm)
  • The plane of the deep‐excision margin
  • Whether the tumor is recurrent or whether it is in a field of previous radiotherapy
  • The immunocompetency of the patient

Treatment options for primary cSCC

The first-line treatment that should be offered to people with resectable primary cSCC is surgical excision.

Determine peripheral tumor margins under bright lighting with magnification or with dermoscopy.

The following should be offered to patients with cSCC who have one or more involved margins or margins less than 1 mm, in whom patient or tumor factors suggest higher risk:

  • Wide local excision (delayed reconstruction likely)
  • Mohs micrographic surgery
  • Adjuvant radiotherapy

Active treatment can be offered to immunosuppressed cSCC patients who have one or more clear‐but‐close (< 1 mm) or involved margins, followed by structured follow‐up and surveillance.

If patients have symptomatic perineural invasion or radiologic evidence of perineural invasion, their case should be discussed by a specialist skin cancer multidisciplinary team.

Mohs micrographic surgery can also be considered in selected patients with cSCC after discussion by a specialist skin cancer multidisciplinary team; this particularly applies to cases in which tumor margins are difficult to delineate or in locations where tissue conservation is important for function.

Before considering radiotherapy in patients with histologically proven cSCC, discuss the case with a multidisciplinary team—either a local skin cancer multidisciplinary team or a specialist skin cancer multidisciplinary team—with a clinical oncologist present.

Curettage and cautery with curative intent can be considered in immunocompetent patients with low-risk, small (< 1 cm), well‐defined, nonrecurrent cSCC.

Locally advanced, recurrent, and metastatic cSCC

In patients with the following variables, an individualized specialist skin cancer multidisciplinary team should be involved to include multimodality and imaging treatment plans:

  • Regional lymph node metastasis
  • Immunocompromise with locally advanced and/or metastatic cSCC
  • In-transit metastases from cSCC
  • Metastatic cSCC, with the patient having experienced further locoregional relapse following lymphadenectomy

Therapeutic regional lymphadenectomy should be offered to patients with head and neck cSCC with regional lymph node metastasis. It should also be offered to patients with non–head and neck cSCC who have regional lymph node metastases in axillary, inguinofemoral, or other peripheral draining nodes.

Adjuvant radiotherapy should be offered after therapeutic regional lymphadenectomy to patients with cSCC who have high‐risk pathology.

Insufficient evidence to support any recommendation for cSCC

The evidence is insufficient to support any recommendations for the following therapies in the treatment of cSCC:

  • Cryotherapy
  • Carbon dioxide laser therapy
  • Topical therapies