BACKGROUND: Intraoral adenoid cystic carcinoma (ACC) arising from minor salivary glands (MSG) is a rare malignancy associated with delayed diagnosis and unfavorable outcomes. This study aimed to comprehensively review ACC of MSGs, focusing on clinical characteristics, imaging modalities, treatment approaches, and long-term outcomes.
METHODS: A systematic search was conducted in PubMed, Web of Science, and MEDLINE databases to identify relevant articles reporting cases of ACC of MSGs between January 1997 and March 2023. The study was registered in PROSPERO (ID: CRD42023449478). A total of 10 studies that met the inclusion criteria were selected for critical review. In total, 902 patients were diagnosed with ACC of MSGs with an age range of 44.3 to 63 years, and an average age of 56.6 years. The female to male ratio ranges from 1:1 to 2.4:1. Regarding the primary site of ACC, the palate was the most common location, accounting for 30.5% to 83.3%, followed by the buccal mucosa, floor of the mouth, and lip and the retromolar area. For histology, the solid mass pattern was the most prevalent, seen in 95.2% of patients, followed by the cribriform pattern. Regarding treatment modalities, surgery was the most common approach, applied in 76.3% of cases, with a combination of surgery and radiotherapy used in 29.0% of cases. A smaller fraction, 3.2%, received a combination of surgery, chemotherapy, and radiotherapy, and 8.3% underwent radiotherapy alone. Local recurrence rates varied between 1% and 28.5%, and distant metastasis occurred in 18.2% to 33.3% of cases, predominantly to lymph nodes (14.5%). An analysis of overall survival across various stages and patient numbers indicated a 5-year survival rate of 68.0%. The findings of this study provide valuable insights for physicians in making treatment decisions and emphasize the need for ongoing research and collaborative clinical efforts to improve the management and outcomes of this challenging disease.
CONCLUSIONS: ACC of MSGs is a multifaceted condition typically manifesting as asymptomatic enlargement and ulceration. This disease is marked by distinct histopathological patterns and perineural invasion (PNI). Recognizing these distinctive aspects is key in shaping the treatment plan, which can range from surgical procedures to radiation therapy, chemotherapy, and evolving targeted treatments. Continuous research and collaborative clinical efforts remain critical for ongoing progress in the treatment and management of this challenging condition.

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.

Lymphoepithelial carcinoma (LEC) of the oral mucosa is a rare histopathologic subtype of squamous cell carcinoma (SCC), which shares morphologic similarities with nasopharyngeal carcinoma (NPC), non-keratinizing undifferentiated subtype. The admixture of neoplastic epithelial tumor cells and a dense lymphoplasmacytic infiltrate makes microscopic diagnosis challenging. LEC etiopathogenesis has been variably associated with Epstein-Barr virus (EBV) infection, depending on the specific anatomic location and racial predilection, with a higher incidence in endemic populations. Although described in several subsites of the head and neck region, including the major salivary glands, the oral mucosa is considered an infrequent location for LEC development, deriving either from minor salivary glands (MSGs) or the surface epithelium. Herein, we report a rare case of an EBV-negative LEC arising from the oral surface epithelium, presenting as gingival swelling, and review the pertinent English-language literature, which revealed only 26 previously reported oral LECs. Our case is only the fourth oral LEC originating from the surface epithelium and the first one to affect the gingiva.

Biopsy is a surgical procedure performed to collect a portion of tissue or organ for diagnostic studies. The aim of the present manuscript is to describe state-of-the-art major and minor salivary gland biopsy techniques and assess the indications and complications of other salivary gland biopsy techniques. A search was performed using the following MeSH terms: biopsy, fine-needle biopsies, image-guided biopsies, frozen sections, and salivary glands disease. A current overview of major and minor salivary glands biopsy techniques was provided. In the oncological field, a comparison was made between the most widely used biopsy method, ultrasound-guided fine-needle aspiration biopsy (US-FNAB), and an alternative method, ultrasound-guided core needle biopsy (US-guided CNB), highlighting the advantages and disadvantages of each. Finally, intra-operative frozen sections (IOFSs) were presented as an additional intraoperative diagnostic method. Minor salivary gland biopsy (MSGB) is the simplest diagnostic method used by clinicians in the diagnosis of inflammatory and autoimmune diseases. In neoplastic lesions, US-FNAB represents the most performed method; however, due to its low diagnostic accuracy for non-neoplastic specimens, US-guided CNB has been introduced as an alternative method.

BACKGROUND: Cribriform adenocarcinoma of the tongue and minor salivary glands (CATMSG) is a rare neoplasm, accounting for less than 1% of salivary gland tumors. In the past it has been considered a possible variant of polymorphous low-grade adenocarcinoma (PLGA), while nowadays it is accepted as a provisional entity in the WHO classification. The aim of this paper is to systematically review the existing literature about CATMSG with a particular attention to differential diagnosis and prognostic factors.
METHODS: This study was performed in accordance with the PRISMA checklist. A comprehensive search in PubMed, Cochrane, and Google Scholar databases was carried out in June 2021, in partnership with a medical librarian, without time restriction. Search items include the following keywords: \"cribriform adenocarcinoma of the tongue\" OR \"cribriform adenocarcinoma of the tongue and minor salivary glands.\"
RESULTS: A total of 56 patients were evaluated. Patient age across the studies ranged from 13 to 85 years (mean 59.6 year). The most common site of involvement was the tongue (58.9%), followed by palate (19.6%), tonsil (7.1%), buccal (3.6%) and reticular mucosa (3.6%), lip (3.6%), retromolar pad (1.7%), and floor of the mouth (1.7%). Lymph node involvement at the diagnosis was very common (58.9%), while there was no evidence of patients diagnosed with metastatic disease. The most common surgical approach was surgical excision (17, 30.3%); neck dissection was performed in 16 patients (28%). Radiotherapy was the most common adjuvant treatment reported (46.4%); only one patient underwent adjuvant chemotherapy (1.7%). Five patients experienced a recurrence (8.8%).
CONCLUSIONS: To our knowledge, only 56 five cases of CATMSG have been previously described. The results of this review seem to confirm the low frequency of relapses and distant metastases, but we observed that almost 60% of cases presented with cervical lymph node involvement. In our opinion, CATMSG should be considered as a distinct tumor entity from PLGA.

BACKGROUND: Adenoid cystic carcinoma (ACC) is a rare tumor developed in minor salivary glands, the palate being the most common site.
METHODS: Here, we report a case of a 58-year-old man with a 3-year-growing swelling in the right palate diagnosed with high grade transformation adenoid cystic carcinoma. The exam revealed a 4 cm large mass. A tumor resection with a radical neck dissection was performed.
CONCLUSIONS: High grade transformation in adenoid cystic carcinoma is recently described by Cheuk et al. in 1999. This transformation has more aggressive behavior than conventional solid ACC and has usually been associated with recurrences, early distant metastasis, and greater mortality.
CONCLUSIONS: The aim here is to highlight clinical, histopathological, therapeutic and prognostic aspects of high-grade transformation in ACC with literature review.

BACKGROUND: Basal cell adenocarcinomas (BCACs) arise from the minor salivary glands in the upper respiratory tract and are extremely rare. In this report, we present an unusual case of a 57-year-old male with BCAC that arose from the nasopharynx. To our knowledge, this is the first case report of nasopharyngeal BCAC.
METHODS: In August 2010, a 57-year-old Chinese male presented with epistaxis and decreased hearing for 1 month. He was diagnosed with BCAC of the solid type that arose from the nasopharynx. The patient received radiotherapy alone and exhibited a complete response. A follow-up at 72 months did not detect any evidence of disease recurrence or metastasis. A comprehensive literature review revealed only 7 previously reported cases of BCAC in the upper respiratory tract. Surgery is the first choice to treat BCAC but may impair maxillofacial function. Radiotherapy is reserved for inoperable cases.
CONCLUSIONS: Radiotherapy can achieve good local control and preserve maxillofacial function; therefore, this treatment may be a suitable option for patients who are not good candidates for surgery.

Primary intestinal-type adenocarcinoma (ITAC) of the oral tongue is an extremely uncommon malignancy with only 3 cases reported in the literature. This high-grade malignancy originates from metaplasia of minor salivary glands.
A 40-year-old man presented with a gradually enlarging midline oral tongue mass, odynophagia, and dysphagia. Management included a median lingual glossectomy, bilateral neck dissections, and adjuvant chemoradiation with 5-fluorouracil (5-FU). Additional chemotherapy with folinic acid, fluorouracil, and oxaliplatin (FOLFOX) was given to mimic therapy in colonic adenocarcinomas.
Thirteen months after surgery and adjuvant chemoradiotherapy, there is no evidence of locoregional or distant disease. His diet and speech have normalized after reconstruction without free tissue transfer.
We report the fourth case of oral tongue ITAC, and present the first histologic evidence of metaplasia of oral cavity salivary epithelium. We also discuss adjuvant therapy recommendations given the lack of clarity for treatment of this rare disease.

Basal cell adenocarcinoma (BCAC) of salivary glands is uncommon low-grade malignancy. Only 19 cases of preoperative cytology were reported up to date. We present here a new case of BCAC arising in the minor salivary gland. Tumor was composed of clustered or isolated roundish, dark cells with small and regular nuclei. Chromatin was dusty with small nucleoli. Cytoplasm was gray and scant. Clusters showed typical and characteristic basal architecture with peripheral palisading neighboring eosinophilic basal membranes. A false-negative diagnosis of basal cell adenoma was rendered. In our knowledge it is the first cytological description of BCAC arising in the minor salivary gland.

Salivary gland cancers are a complex group of tumours with variations in location, type and grade, all of which influence their biological behaviour. The understanding of salivary gland pathology has evolved at the molecular level in the last decade leading to identification of distinct entities, development of improved methods of diagnosis as well as identifying therapeutic targets for selected high-grade tumours. This article focuses on these advances and their impact on the management of primary salivary gland cancers.