INTRODUCTION
Squamous cell carcinoma (SCC) is one of the most common malignant neoplasms, and its incidence is increasing.1 Some patients are considered poor candidates for surgery due to the location of the tumor, health conditions, or having numerous lesions simultaneously. Human papillomavirus (HPV) infection may be involved in the development of SCC in some patients.2 Previous reports have shown a significant reduction of the rate of SCCs after administration of quadrivalent human papillomavirus vaccine in patients with a history of multiple SCCs.3 Additionally, various cases of inoperable SCC were successfully treated with systemic and intralesional (IL) HPV vaccine on the leg and dorsal hand.4-7 We report a case of a 74-year-old man with a recurrent SCC in situ on the left fourth finger successfully treated with intralesional and systemic administration of recombinant human papillomavirus 9-valent vaccine (Gardasil-9 Merck & Co Inc).
CASE
A 74-year-old man with a 10-year history of biopsy-proven SCC in situ of the left fourth dorsal finger and no known past medical history presented with a large erythematous scaly
plaque on the left ring finger (Figure 1A). A shave biopsy was performed, showing SCC in situ (Figure 2A). The patient had Mohs micrographic surgery on the affected area 5 years previously with tumor recurrence. Subsequently, the patient was treated with topical tretinoin 0.1%, Imiquimod 5%, and 5-fluorouracil 5% compound cream three times weekly for ten weeks with no improvement. After the patient declined radiotherapy and additional surgery, the patient was offered treatment with Gardasil-9. He received an intramuscular (IM) vaccine injection at week 0, week 9, week 28, and one final booster on week 63. IL injections were administered at weeks 3, 7, and 23, and one final IL at the time of the booster shot (week 63). During the course of the administration of IM and IL the tumor was noted to drastically decrease in size, but still retained a small (less than 2 mm) focus.
plaque on the left ring finger (Figure 1A). A shave biopsy was performed, showing SCC in situ (Figure 2A). The patient had Mohs micrographic surgery on the affected area 5 years previously with tumor recurrence. Subsequently, the patient was treated with topical tretinoin 0.1%, Imiquimod 5%, and 5-fluorouracil 5% compound cream three times weekly for ten weeks with no improvement. After the patient declined radiotherapy and additional surgery, the patient was offered treatment with Gardasil-9. He received an intramuscular (IM) vaccine injection at week 0, week 9, week 28, and one final booster on week 63. IL injections were administered at weeks 3, 7, and 23, and one final IL at the time of the booster shot (week 63). During the course of the administration of IM and IL the tumor was noted to drastically decrease in size, but still retained a small (less than 2 mm) focus.
