Perineural and lymphovascular invasion in squamous cell carcinoma of the tongue.

BACKGROUND: Perineural invasion (PNI) and lymphovascular invasion (LVI) may be adverse prognostic indicators in squamous cell carcinoma (SCC) of the tongue. METHODS: The percentages of histological PNI and LVI were determined in 335 patients with tongue SCC. Sixty tumours originally reported as negative for these features were tested to determine how many more were positive with "immunohistochemical enhancement." RESULTS: PNI was found in 141 (42.1%) and LVI in 51 (15.2%) patients. 79.4% of the 141 patients who had PNI and 72.6% of the 51 with LVI had a T3 or T4 tumour. Lymph node metastasis was identified in 145 (51.2%) of the 280 patients who had undergone neck dissection; 58.2% of the 141 patients with PNI and 80.4% of the 51 patients with LVI had lymph node metastasis. There was a highly statistically significant correlation between PNI with increasing pT (P < .00001) and pN (P < .0001) stage, and a statistically significant correlation between LVI and pT stage (P < .001), the association of LVI with pN status could not be reliably tested statistically. Immunohistochemistry for S100 identified five further cases of PNI, but review of the original H&E showed the feature was present in four and had been missed at original reporting. CD31 identified three further possible cases of LVI and D2-40 none. The endothelium of some vascular channels was positive for both CD31 and D2-40 and cross-reactivity with other cells compromised interpretation. CONCLUSIONS: Histological identification of PNI and LVI per se remains of uncertain prognostic significance. "Immunohistochemical enhancement" offered little benefit.

Cystic Squamous Cell Carcinomas of the Jaws: Twelve Cases Highlighting Histopathological Pitfalls.

Cystic squamous cell carcinomas (SCCs) of the jaws, including carcinoma cuniculatum, are rare, slow growing, and relentlessly invasive. The aim of this article is to present 12 cases, 4 of which were designated as carcinoma cuniculatum on the basis of deeply endophytic, anastomosing channels of cystic stratified squamous epithelium and keratin microabscesses. The other 8 were also cystic, but more heterogeneous morphologically and were diagnosed as well differentiated SCCs. Six patients were female, 6 were male (mean age = 74.0 years, range = 50-94 years). Six tumors affected the mandible, 6 the maxillary alveolus with or without extension into the hard palate. All patients underwent primary resection with neck dissection and were staged as T4a N0 M0. In 4 patients, diagnosis was delayed as a result of superficial biopsies and/or confusing histopathology. Cystic SCCs of the jaws can be difficult to diagnose and clinicoradiological correlation is essential. Long-term follow-up is mandatory.

Dentigerous Cyst and Ameloblastoma of the Jaws.

AIM: To determine how many ameloblastomas were misdiagnosed as dentigerous cysts (DCs) by correlating the radiological and histopathological features of a series of both entities. METHODS AND RESULTS: Histopathology reports and radiological imaging of 135 DCs and 43 ameloblastomas were reviewed. Any clinical or radiological feature that suggested that the diagnosis of DC was wrong-for example, absence of an unerupted tooth-prompted review of the original histology. A total of 34 cases coded as DC at diagnosis were excluded; in the remaining 101 patients, the clinicoradiological and histopathological features were consistent with DC in 96 (95.0%). Review of the histology revealed that 4 patients had actually had odontogenic keratocysts (OKCs) and one a luminal/simple unicystic ameloblastoma (UA). One other OKC and 3 other ameloblastomas (1 luminal UA, 2 solid/multicystic) had originally been diagnosed as DC; these had been identified prior to the study. Of the 9 misdiagnosed patients, 6 were ≤20 years old. Clinically, DC had been the only, or one of the differential, diagnoses in 7 patients; in the other 2, the clinical diagnosis was radicular cyst. In none of the 4 misdiagnosed ameloblastomas was the radiology compatible with a diagnosis of DC. Incorrect terminology had been used on the histopathology request form in 5 of the 34 excluded cases where the clinical diagnosis was DC, despite the cyst being periapical to an erupted carious or root-filled tooth. CONCLUSIONS: The entire clinical team must ensure that a histopathological diagnosis of DC is consistent with the clinicoradiological scenario, particularly in younger patients.

Synchronous metastatic adenoid cystic and squamous cell carcinoma of the cervical lymph nodes 31 years after ablation of the primary palatal tumour.

The coexistence of different types of malignancy in cervical lymph nodes has been reported previously. We report the first case, to the best of our knowledge, of concurrent metastatic adenoid cystic carcinoma and squamous cell carcinoma (SCC) in cervical lymph nodes. A primary SCC developed three decades after treatment for adenoid cystic carcinoma of the palate, and the synchronous metastases became clinically apparent the following year. The aetiology of the SCC may have been related to radiotherapy or smoking. Whether the adenoid cystic carcinoma would have remained dormant, or was reactivated after perturbation of host defence mechanisms, is not known.

Bilateral asynchronous renal cell carcinoma with metastatic involvement of the tongue.

Renal cell carcinoma (RCC) has a propensity for distant organ metastasis and late recurrence, involving not only the ipsilateral but also contralateral kidney. Lingual metastasis by RCC is rare. We present an unusual case of bilateral asynchronous RCC. Involvement of the right kidney was discovered only after a metastatic tongue lesion was diagnosed. The original RCC had been treated by left nephrectomy 14 years previously. Due to end-stage primary pulmonary malignancy, and poor function of the remaining kidney, immunotherapy was unsuitable. Palliative local resection of the lingual metastasis alleviated functional difficulties and was preventative against airway obstruction, but the patient died five months later.