Polymorphous low-grade adenocarcinoma of the head and neck. Am J Clin Oncol. 2014;37:624-626. [PMID: 23428952 DOI: 10.1097/coc.0b013e31827e5537]

Polymorphous Adenocarcinoma: A Systematic Review of the Literature and Presentation of Two Cases in a Less-Considered Anatomical Site

BACKGROUND

Polymorphous adenocarcinoma (PAC) is the second-most common malignant tumour of the minor salivary glands. Although PAC predominantly affects the palate, it can also involve the buccal mucosa. This systematic review aims to investigate the literature data about PAC. Furthermore, we report two cases of patients affected by PAC in an infrequently considered anatomical site.

METHODS

According to PRISMA guidelines, a systematic review search was conducted on PubMed, Scopus, and Web of Science. Observational studies conducted on patients with a histological diagnosis of PAC were selected and analysed. Furthermore, two cases of patients with PAC affecting the buccal mucosa were reported.

RESULTS

Twenty-nine studies were included, and 143 patients affected by PAC were analysed (62 males, 75 females, and 6 undefined, with a mean age of 57.4 ± 14.5 years). The palate was the most affected site (99/143, 69.2%), followed by the buccal mucosa (12/143, 8.4%). Moreover, we report two cases of patients with PAC affecting the buccal mucosa (one male and one female, with a mean age of 70.5 ± 2.5 years).

CONCLUSIONS

The present study underscores the importance of considering the buccal mucosa as a possible location of minor salivary gland tumours; although it is a less-considered affliction, it is not uncommon.

Retrospective Analysis of Clinicopathological Characteristics of Lacrimal Gland Pleomorphic Adenoma and Mechanism of Tumorigenesis by the Imbalance Between Apoptosis and Proliferation

BACKGROUND Lacrimal gland pleomorphic adenoma (LGPA) is the most common clinically benign epithelial tumor of the lacrimal gland and is predominantly comprised of epithelial cells and interstitial components. At present, the exact pathogenesis of LGPA remains unclear. Previous research has indicated that the occurrence of LGPA may be related to excessive cell proliferation. MATERIAL AND METHODS This study observed the clinicopathological characteristics of LGPA and investigated the tumorigenesis mechanism of cell over-proliferation caused by the imbalance between apoptosis and proliferation. A total of 27 cases were collected from the Department of Ophthalmology of the Affiliated Hospital of Chengde Medical University and the Third Medical Center of Chinese PLA General Hospital from April 2017 to November 2019. Hematoxylin-eosin (HE) staining and immunohistochemical staining were used to observe the pathological characteristics and analyze the expression of bcl-2 and bax in the lacrimal gland. RESULTS Compared with normal lacrimal gland tissues, LGPA tumor tissues had obvious changes in pathological morphology. The expression of bcl-2 in LGPA lesion tissues was dramatically higher (P<0.001), the expression of bax was not significantly different between groups (P=0.25), but the ratio of bcl-2/bax was significantly higher in tumor tissues (P=0.01). CONCLUSIONS We found that the lacrimal gland tumor tissues had obvious excessive proliferation in pathomorphology, which revealed the necessity of complete surgical removal of the capsule from the perspective of pathological morphology and provided a theoretical basis for the hypothesis that the imbalance between apoptosis and proliferation could lead to cell hyperproliferation.

SOX10 and GATA3 in Adenoid Cystic Carcinoma and Polymorphous Adenocarcinoma

Differentiating between adenoid cystic carcinoma (AdCC) and polymorphous adenocarcinoma (PAC) can be difficult on small biopsies and cytologic specimens. As such, further characterization of their immunophenotype may aid in distinction. Previous studies have found AdCC to be SOX10+/GATA3 variable and PAC to be GATA3 negative. SOX10 expression in PAC has, as yet, not been established. We performed GATA3 and SOX10 immunohistochemistry on whole sections of 25 cases each of AdCC and PAC (including both classic PAC and the cribriform variant) to assess whether these markers are of diagnostic utility in distinguishing between these entities. SOX10 was found to be positive in 100% of PAC and AdCC whereas GATA 3 was immunoreactive in 45% of AdCCs and 20% of PAC. While this is the first series to compare SOX10 and GATA3 staining in these two tumor types, their frequent expression and similar staining patterns render them of limited value in discriminating between these neoplasms.

Polymorphous Low-Grade Adenocarcinoma: A Proposed Reconstruction Protocol Based on Past Surgical Experience

BACKGROUND

To propose a reconstructive protocol based on surgical management experience of polymorphous low-grade adenocarcinoma (PLGA) and the location of the primary lesion.

METHODS

Data on the surgical management and the reconstructive technique of 14 histologically conformed patients with PLGA, all treated by the same surgeon, were analyzed and evaluated.

RESULTS

Mean follow-up period in our series was 6.2 years. Mean age at diagnosis was 55.5 years and female to male ratio was 2.2:1. The most common presenting sign was a nonpainful lump or mass in an intraoral location. Most patients were managed by wide local excision and reconstruction method varied from primary closure to the use of radial forearm graft. Recurrence appeared in one of the patients in this series, while 2 required further radiation therapy. A protocol for reconstruction of intraoral patients with PLGA is suggested based on our analysis.

CONCLUSION

Surgical management is the gold standard for PLGA treatment. Neck dissection is recommended only in patients with presurgery fine-needle aspiration confirmed lymph node involvement. The reconstruction depends mainly on location and size of the primary lesion.

Ameloblastoma vs basal cell carcinoma: an immunohistochemical comparison

Despite behavioral mimicry of ameloblastoma (AB) and basal cell carcinoma (BCC), they are classified at 2 extremes within pertinent WHO classifications with respect to benign and malignant designation. This study aims to appraise the current allocation of AB in the classification through an immunohistochemical comparison of some aspects of behavior with BCC. Sections from retrospectively retrieved formalin-fixed, paraffin-embedded tissue blocks of AB (n = 37) and BCC (n = 34) were comparatively examined for the immunohistochemical expression for Ki-67, Bcl-2, MMP-2, MMP-9, CD31, and D2-40 monoclonal antibodies. No statistically significant differences between the tumors were found regarding the immunoexpressions of Bcl-2 (P = .252), CD31 microvessel density (P = .895), lymphatic vessel density (P = .642), and MMP-9 stromal expression (P = .083). MMP-2 expression was significantly higher in epithelial and stromal regions of AB (P = .009 and P = .001, respectively), whereas Ki-67 and MMP-9 epithelial expressions were significantly higher in BCC (P < .000 and P = .026, respectively). Within the studied immunohistochemical attributes for tumor behavior, the study accentuated the overall behavioral mimicry of the tumors and indicated that BCCs surmount ABs by the proliferative rate only.

Relationship and interactions of curcumin with radiation therapy

Curcumin is widely reported to have remarkable medicinal - and antineoplastic - properties. This review details curcumin’s relationship with radiotherapy (RT), principally as a radiosensitizer for various malignancies and a radioprotector for normal tissues. First, examples of radiosensitization are provided for various cancers: Pediatric, lymphoma, sarcoma, prostate, gynecologic, pancreas, liver, colorectal, breast, lung, head/neck, and glioma. It is not the purpose of this article to comprehensively review all radiosensitization data; however, high-quality studies are discussed in relationship to currently-controversial RT questions for many cancers, and thus the importance of developing a natural radiosensitizer. Attention is then shifted to radioprotection, for which supporting research is discussed for the following RT toxicities: Dermatitis, pneumonitis, cataractogenesis, neurocognition, myelosuppression, secondary malignancies, and mucositis/enteritis. Though there is fewer data for radioprotection, the overall quality of clinical evidence is higher, and small clinical trials implicating the efficacy of curcumin for RT toxicities (vs placebo/current therapies) are also detailed. Though the overall level of evidence for curcumin as a radiosensitizer and radioprotector is low, it must be recognized that risks of adverse effects are exceedingly low, and clinicians may need to judge the yet-unproven rewards with low toxicity risks.

Concurrent chemoradiotherapy in older adults with squamous cell head & neck cancer: Evidence and management

OBJECTIVE

Treatment for head and neck cancers incurs substantial associated morbidities, which can be of potentially greater significance in older patients. Though the geriatric population forms a substantial portion of patients with head and neck cancers, this group remains underrepresented in large clinical trials. Hence, management for this unique subpopulation remains empiric and mostly based on data from younger patients.

MATERIALS AND METHODS

Review of key publications on geriatric patients treated for head and neck cancers.

CONCLUSIONS

We discuss data regarding chemoradiation for head and neck cancers, as well as management of associated side effects in this population. We encourage oncologists to treat older patients not as a homogeneous subpopulation, but rather assess several factors associated with potential tolerance to chemoradiotherapy. Aggressive supportive treatments for chemoradiotherapy toxicities are highly encouraged in this population, and with new technical/technological developments, there is potential to continually reduce toxicity in this cohort in the future.

Polymorphous low-grade adenocarcinoma: A Danish national study

OBJECTIVES

To present a national series of polymorphous low-grade adenocarcinoma (PLGA) patients, including survival rates and an analysis of prognostic factors.

MATERIALS AND METHODS

By merging three Danish nationwide registries, 73 patients diagnosed with PLGA from 1990 to 2005 were identified. Histological slides were reviewed and data concerning demographics, tumour site, clinical stage, treatment profiles and follow-up were retrieved. Survival estimates and prognostic factors were evaluated by comparing Kaplan-Meier plots using the Mantel-Haenszel log-rank test.

RESULTS

Of the 73 patients, 47 (64%) were female. Median age was 58years. The most common location was the palate (73%). Median latency was five months. Recurrence was seen in 13% of patients. Overall survival (OS), disease-specific survival (DSS) and recurrence-free survival (RFS) rates after 10years were 73%, 99% and 83%, respectively. Univariate analyses suggested that free resection margins significantly improve RFS.

CONCLUSION

PLGA usually has an excellent survival outcome even in cases of advanced stage disease and locoregional recurrence. Primary choice of treatment should be complete surgical excision. Although there is no convincing evidence for the efficacy of adjuvant radiotherapy, it should still be considered, particularly in cases of involved resection margins and advanced stage disease. Late recurrences are common and respond well to salvage therapy.

Polymorphous low-grade adenocarcinoma of the upper lip: 11 cases of an uncommon diagnosis

OBJECTIVE

The aim of this case study was to describe an international case series of polymorphous low-grade adenocarcinoma (PLGA) affecting the upper lip.

MATERIAL AND METHODS

Over a 30-year-period, the files of five pathology services were reviewed for PLGA affecting the upper lip. Hematoxylin and eosin-stained slides were reviewed by three oral and maxillofacial pathologists, and microscopic features were described. Clinical data were retrieved from patients' medical records.

RESULTS

The review identified 11 cases of upper lip PLGAs, with a complete set of clinical data available for 5 cases. There was a male predominance (1.2:1), and the mean age was 58.7 years. Most cases presented as small asymptomatic swellings that resembled benign tumors. All patients underwent surgery, and no recurrences or metastases were reported in the 8 cases from which follow-up data were available. Microscopically, the typical polymorphic architectural arrangement of PLGA was seen in all cases, with lobular, trabecular, papillary, and cribriform patterns identified. Perineural invasion, normal gland entrapment, Indian filing, and concentric growth were frequently identified.

CONCLUSION

PLGA must be included in the list of differential diagnoses of tumors affecting the upper lip because of its similar clinical presentation to benign entities. The follow-up data available from 8 of 11 cases suggest that these tumors follow a low-grade clinical course, similar to the majority of palatal cases of PLGA.