Human Papillomavirus (HPV) | Figure 4.5
A: Pityriasis rosea, face (Courtesy of
Dr. Paul Getz) B: Kaposi’s sarcoma
Courtesy of National Cancer Institute
C: Verruca vulgaris |
| Figure 4.6
A: Bowenoid papulosis*
B: Verrucous carcinoma on lip
in betel leaf chewer*
*Courtesy of Dr. Shyam B.
Verma, Vadodara, India |
- Genome encodes “E” (early) and “L” (late) proteins
- “E” proteins (E1–E7) code for viral DNA replication; E6 and E7 oncogenes lead to keratinocyte immortalization; low levels expressed in basal layer
- “L” proteins (L1 and L2) code for viral structural proteins (form outer shell: virion), expressed in superficial epithelium
- Transmission mainly via direct skin contact, less likely via fomites; basal keratinocyte target of HPV (long-term reservoir of viral DNA)
- Divided into nongenital and genital infections; also divided into benign or low risk (HPV 6/11) and high risk (HPV 16/18) types
- Gardasil® vaccine: composed of L1 capsid protein with four types of recombinant HPV (type 6, 11, 16, 18)
- Cervarix® vaccine: L1 protein for HPV 16 and 18
- Clinical manifestations of HPV infection:
- Common, plantar, and flat warts (Figure 4.5C)
- Condyloma acuminata: lesions without significant scale in genital area
- Bowenoid papulosis: red-brown papules or plaques involving genital and/or perineal area (clinically appear as genital warts, but histology consistent with Bowen’s disease) (Figure 4.6A)
- Verrucous carcinoma: “semi-malignant” (Figure 4.6B)
- Florid oral papillomatosis: widespread verrucous carcinoma in oral cavity
- Buschke–Lowenstein tumor: large cauliflower-like tumor of anorectum and external genital, focal malignant transformation may occur
- Epithelioma cuniculatum of sole: slow-growing warty mass on sole
- Focal epithelial hyperplasia (Heck’s disease): papules on buccal, gingival, labial mucosa resembling flat warts
- Epidermodysplasia verruciformis: sporadic or AR inheritance, abnormal susceptibility of skin to HPV; red-brown macules with mild scale on face/trunk or flat-topped papules on hands resembling flat warts (malignant transformation in 50% patients)
- Histology: papillomatosis, massive orthokeratosis, columns of parakeratosis, coarse keratohyalin granules of variable size, vacuolated cells (koilocytes), dilated and thrombosed capillaries
| | | | | | | Table 4-1 HPV Subtypes | | | Lesion | | HPV Types
(Frequent) | | HPV Types
(Less Frequent) | | | Common wart | | 1, 2, 4 | | 26, 27, 29, 41, 57, 60, 63, 65 | | | Plantar wart | | 1 | | 2, 4, 63 | | | Flat wart | | 3, 10 | | 28, 29 | | | Butcher’s wart | | 2, 7 | | 1, 2, 3, 4, 10, 28 | | | Epidermodysplasia
verruciformis (EV) | | 2, 3, 5, 8–10, 12, 14, 15, 17 | | 19–25, 36–38, 46, 47, 49, 50 | | | Focal epithelial
hyperplasia (Heck’s) | | 13, 32 | | {Different sources will have conflicting
HPV types for same entity} | | | Verrucous carcinoma | | 6, 11 | | | | Condyloma acuminata | | 6, 11 | | 40, 42–44, 51, 54, 55, 61, 70, 72, 81 | | | Bowenoid papulosis | | 16, 18 | | 26, 31, 33, 35, 39, 45, 51–53, 56, 58, 59, 62, 66, 68, 73 | | | Digital SCC | | 16 | | 34, 35 | | | SCC (in EV) | | 5, 8 | | 14, 17, 20, 47 | | | Cervical cancer | | 16, 18 | | 31, 33, 35, 39, 45, 51, 52, 56, 58, 66, 68, 70 | | | | | | | |
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