Lewis, Jean E.

AbstractBackgroundParotid gland mucoepidermoid carcinoma (MEC) has published five‐year cancer‐specific survival (CSS) rates of 77%–97%, with variance related to grade.MethodsPatients receiving primary surgery for parotid gland MEC from 1995 to 2014 at a tertiary medical center underwent clinical review, histopathologic review, and cytogenetic analysis. Survival outcomes were evaluated.ResultsAmong 58 patients, T/N/M classification was as follows: T1 in 35 patients, T2 in 14, T4a in 9, N0 in 53, N1 in 2, N2b in 3. Histologic grade was low in 27, intermediate in 17, and high in 12 patients with 98% MAML2 positivity. All patients underwent parotidectomy, and seven patients received adjuvant radiation therapy. CSS was 100% at 5 years and 94.1% at 10 and 15 years. Two patients experienced locoregional recurrence.ConclusionsTreatment with adequate surgical resection and adjuvant radiation therapy for high‐grade or advanced‐stage tumors yields excellent survival, independent of clinical stage or pathologic grade.

Abstract Context.—Granular cell tumor (GCT) is a rare tumor of nerve sheath origin with a predilection for upper aerodigestive tract, skin, and soft tissue. The neoplastic cells typically express S100 and CD68 (KP-1), the latter due to cytoplasmic lysosome content. However, the histogenesis of this tumor is unknown. Additionally, distinction between benign and malignant GCT is difficult because of histologic similarity and lack of reliable criteria that can predict clinical behavior. Objective.—To perform a comparative, side-by-side immunohistochemical assessment of the traditional immunohistochemical markers for GCTs (S100, CD68), along with the newer markers (inhibin-α, protein gene product 9.5) for these tumors. Design.—To address diagnostic and prognostic issues, we studied 30 specimens of GCT (27 primary and 3 recurrent tumors, 2 of which occurred consecutively in the same patient) for (1) nuclear pleomorphism, prominent nucleoli, necrosis, spindling, high nuclear-cytoplasmic ratio, and mitoses; (2) immunohistochemical expression of inhibin-α, protein gene product 9.5, S100, CD68 (KP-1), and Ki-67 using the avidin-biotin complex method on formalin-fixed, paraffin-embedded sections; and (3) correlation between tumor grade, proliferative fraction, and clinical data. Results.—Twenty-seven of 27 primary GCTs and 1 of 3 recurrent GCTs had typical histologic features, while the 2 consecutive recurrent GCT specimens from the same patient were atypical (moderate nuclear atypia and prominent nucleoli alone). The mean age for primary GCT was 37.3 years (range, 5–67 years), and mean size was 1.89 cm. None of the cases metastasized. All 30 specimens showed diffuse (2+ to 3+) staining for S100, CD68, and inhibin-α, and 3+ staining for protein gene product 9.5; pseudoepitheliomatous hyperplasia was nonreactive. The Ki-67 proliferative index was less than 1% to 20% in typical nonrecurrent cases, 1% in the typical recurrent case, and 1% and 10% in 2 sequential recurrences of the atypical case. Conclusion.—Our study expands the immunophenotype of GCT (S100, CD68, protein gene product 9.5, and inhibin-α) regardless of location and supports a neural origin. Intensity of immunohistochemical staining had no prognostic significance. Although 1 of the 2 recurrent GCTs had atypical features, the Ki-67 proliferative index did not distinguish reliably between typical (nonrecurrent) and atypical or recurrent GCTs. The significance of inhibin expression with regard to cell differentiation and pathogenesis is unclear and warrants further investigation.

The clinical nature of laryngeal amyloidosis has not been well established, and the natural history of the disease remains a controversial matter. To address these issues, we reviewed the clinicopathologic and immunohistochemical features of 22 cases (11 men and 11 women; mean age, 56 years) of laryngeal amyloidosis. Hoarseness was the most common symptom, and the most frequent site affected was the false vocal cords. Six patients had concomitant tracheal amyloidosis. Paraffin blocks were available for immunostaining in 20 cases. Nineteen cases were positive for amyloid P component. λ‐Light chains were detected in 12 cases and κ‐light chains in 5; three cases did not show definite light‐chain staining. Ten patients underwent repeated operations for persistent or recurrent respiratory tract disease. One patient died of progressive tracheobronchial amyloidosis, but systemic amyloidosis did not develop in any of the patients. Laryngeal amyloidosis is a form of localized amyloidosis characterized by monoclonal light‐chain deposition. Recurrent respiratory tract disease is not uncommon, but the usual clinical course is relatively benign.

AimsBiphenotypic sinonasal sarcoma (SNS) is a locally aggressive tumour that occurs in the sinonasal region. PAX3–MAML3 has recently been identified as a recurrent fusion gene event in this entity; however, a subset of tumours harbour alternative PAX3 rearrangement without the involvement of MAML3. In this study we sought to characterize the molecular profile of a large series of cases, with a special emphasis on tumours with alternative fusions.Methods and resultsForty‐four examples of SNS were screened by fluorescence in‐situ hybridization and reverse transcription polymerase chain reaction to better characterize its molecular profile and identify potential novel fusion genes. Twenty‐four were positive for PAX3–MAML3 (55%), 15 showed rearrangements of PAX3 without MAML3 involvement (34%), one showed rearrangement of MAML3 without PAX3 involvement, and four were negative for the involvement of either gene (9%). Among 15 cases with PAX3 involvement only, three were found to harbour PAX3–FOXO1. Two of these cases arose in the nasal cavities of female patients (aged 31 and 47 years), and one showed bilateral involvement of the nasal cavities of a 35‐year‐old male. A fourth case involved the skull base of a 47‐year‐old male, and was positive for PAX3–NCOA1. Patients with fusion‐negative tumours were slightly older.ConclusionMore than half of the SNSs in this series were positive for PAX3–MAML3. However, a subset of tumours may harbour alternative PAX3 fusion genes or show no involvement of PAX3. Except for a possible weak association between age and molecular profile, the overall morphological and immunophenotypic features of all cases seem to be similar. Because of the rarity of these tumours, the impact of the molecular profile on the clinical course of these tumours remains to be determined.

Objectives/HypothesisTo determine the incidence of level IIB lymph node metastasis in patients with laryngeal or hypopharyngeal squamous cell carcinoma and to evaluate the need for elective and therapeutic neck dissection of level IIB.Study DesignRetrospective cohort study and review of the literature.MethodsPatients with laryngeal or hypopharyngeal squamous cell carcinoma (N = 65) were primarily treated with surgery at Mayo Clinic (Rochester, Minnesota) from 2004 through 2010. Neck dissection specimens were analyzed by a pathologist, and metastases to level IIB were reported. In addition, 18 previously published studies, totaling 1,114 neck dissections, were reviewed.ResultsLevel IIB lymph node metastases were present in 4% and 17% of elective and therapeutic neck dissections, respectively. Ipsilateral IIB metastasis was more common than contralateral IIB metastasis in elective and therapeutic neck dissection specimens. Level IIB lymph node metastasis was not significantly associated with level IIA nodal metastasis, level III nodal metastasis, clinical primary tumor stage, clinical nodal stage, or pathologic confirmation of extracapsular spread in either laryngeal or hypopharyngeal squamous cell carcinoma.ConclusionsThe rate of occult IIB metastasis in laryngeal and hypopharyngeal squamous cell carcinoma is exceedingly low. In a clinically node‐negative case, the ipsilateral and contralateral level IIB nodal packet should not be dissected. For clinically node‐positive cases, ipsilateral level IIB dissection should be performed; contralateral IIB dissection should be performed only when indicated.Level of Evidence4. Laryngoscope, 123:3032–3036, 2013

Objectives/HypothesisTo determine the incidence of level IIB lymph node metastasis in patients with oropharyngeal squamous cell carcinoma (OPSCC) and to evaluate the necessity of level IIB dissection for elective and therapeutic neck dissections.Study DesignRetrospective cohort study.MethodsPatients with OPSCC (N = 348) were surgically managed at our institution from 2004 through 2010. Neck dissection specimens were reviewed by a pathologist, and level IIB metastases were analyzed with respect to clinical and pathologic data.ResultsLevel IIB lymph node metastases were present in 2.5% and 25% of elective and therapeutic neck dissections, respectively. Level IIA metastasis, clinical tumor stage, clinical nodal stage, extracapsular spread, and primary tumor location in the tonsil were significantly associated with level IIB metastasis.ConclusionsThis study uniquely demonstrated a statistically significant association between clinical tumor stage and tonsil subsite with level IIB metastasis in OPSCC. Considering the predicted incidence of nodal metastasis, we conclude that level IIB neck dissection can be omitted in early stage (T1 or T2) clinically node negative (cN0) OPSCC. In patients with a cN0 neck and advanced OPSCC (T3 or T4), primary tumor in the tonsil, or ipsilateral clinically node positive (cN+) and contralateral cN0 neck, level IIB dissection should be considered. Level IIB dissection should be performed routinely in patients with cN+ OPSCC.Level of Evidence4. Laryngoscope, 123:2700–2705, 2013

Granulomatosis with polyangiitis (Wegener’s) (GPA) may mimic IgG4-related disease (IgG4-RD) on histologic examination of some biopsies, especially those from head and neck sites. IgG4 immunostain is often performed in this context for differential diagnosis with IgG4-RD. However, the prevalence of IgG4+ cells in GPA has not been explored. We examined the IgG4+ cells in 26 cases confirmed as GPA by a thorough clinical and pathologic assessment. Twenty-six biopsies consisted of 14 sinonasal/oral cavity/nasopharynx, 7 orbit/periorbital, 3 lung/pleura, 1 iliac fossa/kidney, and 1 dura specimens. Eight of 26 (31%) biopsies revealed increased IgG4+ cells (>30/HPF and >40% in IgG4+/IgG+ ratio). The IgG4+ cells and IgG4+/IgG+ ratio ranged 37–137/hpf and 44–83%, respectively. Eight biopsies with increased IgG4+ cells were from sinonasal(n=4)or orbital/periorbital(n=4)sites. In conclusion, increased IgG4+ cells are not uncommonly seen in sinonasal or orbital/periorbital biopsies of GPA, which could pose as a diagnostic pitfall.

Abstract The head and neck region is a frequent site for potentially confusing incidental benign findings not related to the primary pathologic process and having no impact on patient prognosis. Several lesions are thymic in origin. We report 3 cases of lymphocyte-poor thymic remnants identified in central cervical (level VI) lymph node dissections for unrelated benign and malignant pathology. In each, the rests were nearly completely composed of bland epithelial cells with rare admixed lymphocytes. These cells were immunophenotypically similar to thymic epithelial cells, although they differed in the paucity of associated thymic lymphocytes and lack of Hassall corpuscles. Lymphocyte-depleted thymic remnants in the central cervical compartment are not well described in the literature. It is important to be aware of these and other benign inclusions to avoid making incorrect diagnoses of malignancy.