Skip to main content

Table 1 Differential diagnosis of oral carcinoma cuniculatum, verrucous carcinoma, papillary SCC, and well-differentiated conventional OSCC, respectively

From: Oral carcinoma cuniculatum: an unacquainted entity with diagnostic challenges—a case report

 

OCC

VC

PSCC

Well-differentiated OSCC

Histologic features

 Epithelium

Well-differentiated squamous epithelium

Well-differentiated squamous epithelium

Keratinizing type: dysplastic squamous epithelium non-keratinizing type: immature cells

Well-differentiated squamous epithelium

 Cellular atypia

Absent or minimal (bland squamous cells)

Absent or minimal (bland squamous cells)

Severe (dysplastic squamous cells or immature basaloid cells)

Severe (dysplastic squamous cells)

 Basement membrane

Invasive disruption of the basement membrane

Intact basement membrane with lateral spread

Invasive disruption of the basement membrane

Invasive disruption of the basement membrane

 Growth pattern

Endophytic ± exophytic growth pattern predominantly endophytic growth, however both endophytic and exophytic growth can occur

Exophytic and endophytic growth pattern

Exophytic and endophytic growth pattern

Variable exophytic and/or endophytic growth pattern

 Exophytic component

The surface is usually smooth but maybe exophytic.

When exists the surface has a blunt pebbly ‘cobble stone’ appearance

Typically, the warty verrucous pattern with surface has vertical pointed ‘church spire-like’ fronds that show excessive surface keratin, clefting, and parakeratin plugging

The surface has a papillary ‘filiform’ pattern with thin central cores covered by malignant epithelial cells with minimal or no keratinization

When exists the surface has an irregular, fungating, papillary, or verruciform appearance

 Endophytic component

Endophytic multiple deep burrowing ‘rabbit burrow’ or ‘cuniculi’ pattern of a complex arborizing network of invasive tumor cells with keratin-filled crypts and tortuous cystic structures into connective tissue is the hallmark of this lesion

The proliferating epithelium shows deeply invasive ‘pushing’ front of broad blunt elongated rete ridges and restricted to the lamina propria

The endophytic squamous proliferation of tumor cells into connective tissue

The endophytic squamous proliferation of tumor cells into connective tissue

 

Infiltrating tumor islands

No infiltrating tumor islands

Infiltrating tumor islands

Infiltrating tumor islands

 Invasion/infiltration

Locally destructive, infiltrative tumor

Superficial invasion

Locally destructive, infiltrative tumor

Aggressive locally destructive, infiltrative tumor

 Keratin

Network of keratin-filled burrows and crypts in the connective tissue

Marked surface keratinization, so-called ‘church-spire keratosis’

Variable amount mostly confined to the surface

Abundant

± Keratin pearls

Parakeratosis and parakeratin plugging

± Keratin pearls

++ Keratin pearls

 Metastasis

Rare

Non-metastasizing

Uncommon

Frequent/early

 Recurrence

Rare

Can recur

Can recur

Can recur

Prognosis

Worse prognosis than VC, but better prognosis than both PSCC and conventional OSCC

Better prognosis than OCC, PSCC, and conventional OSCC

Better prognosis than conventional OSCC

Worse prognosis than VC, OCC, and PSCC (According to clinical TNMa staging)

 Therapy

Wide surgical excision for cases with no bone invasion

Subtotal maxillectomy or mandibulectomy with a safety margin for cases associated with bone invasion ± neck dissection in extensive cases

Wide surgical excision

Wide surgical excision + chemo- and/or radiotherapy

Stage I and II tumors are treated with en bloc resection ± neck dissection

Stage III and IV tumors are treated with surgery with neck dissection + chemo- and/or radiotherapy

  1. a TNM: tumor (T), nodes (N), and metastases (M)