In a clinical context, oral lymphomas are very uncommon and frequently challenging to identify. Mucosa-associated lymphoid tissue (MALT) lymphomas are a diverse category of lymphomas that were formerly believed to be formed from B-cells located in the marginal zone, which surrounds B-cell follicles and the surrounding lymphoepithelium. Extranodal organs like the stomach, thyroid, and large salivary glands are where they most frequently appear. As a result, they are accurately identified as extranodal marginal zone B-cell lymphomas (ENMZL). This report presents a case of a 53-year-old female with lower lip swelling, which was diagnosed as a case of marginal low-grade B-cell non-Hodgkin\'s lymphoma after clinical, histopathological, and immunological examinations. Non-Hodgkin\'s lymphoma diagnosis can be aided by pathological examination and biopsy performed early in the lesion\'s development. The dentist has a key role to play in the early diagnosis process.

Mucocele-like lesions (MLLs) of the breast are rare lesions described as dilated, mucin-filled cysts associated with rupture and extracellular mucin in the surrounding stroma. These lesions are of clinical concern because they can coexist with a spectrum of atypical and malignant findings, including atypical ductal hyperplasia, ductal carcinoma in situ, and invasive carcinoma including mucinous carcinoma. Imaging findings of MLLs are nonspecific and varied, although the most common initial finding is that of incidental coarse heterogeneous calcifications on mammography. Occasionally, an asymmetry or mass may be found with or without calcifications, and such MLLs have a higher rate of upgrade to malignancy at excision. Pathology findings are often descriptive given the small sample received from percutaneous biopsy, and the primary consideration is to report any associated atypia, including atypical ductal hyperplasia. There is consensus in the literature that MLLs with atypia on biopsy should undergo excision because of the average reported 17.5% (20/114) upgrade rate to malignancy. The upgrade rate for MLLs without atypia averages 4.1% (14/341). Therefore, imaging surveillance may be a reasonable alternative to excision for MLLs with no atypia on a case-by-case basis. We review MLL imaging findings, pathology findings, and clinical management and present 3 cases from our institution to add to the literature on these rare lesions.

Mucocele-like lesions (MLLs) of the breast are rare neoplasms characterized by dilated, mucin-filled epithelial ducts or cysts that can rupture and expel their contents into the surrounding stroma. They are frequently associated with atypia, dysplastic change, and, more recently, pre-malignant and malignant conditions like atypical ductal hyperplasia, ductal carcinoma, invasive carcinoma, or mucinous carcinoma. The malignant potential of MLLs is often challenging to determine from the initial histologic evaluation of a core-needle biopsy due to copious mucin and low cellularity. Therefore, at initial presentation, MLLs should be surgically excised and thoroughly evaluated for malignancy. In this paper, we present a rare case of an MLL and explore the radiology, histology, carcinogenic potential, diagnostic evaluation, and suggested management of the condition.

BACKGROUND: The management of high-risk breast lesions diagnosed on image-guided core biopsy remains controversial. We implemented a high-risk breast conference attended by breast pathologists, imagers, and surgeons to prospectively review all contemporary cases in order to provide a consensus recommendation to either surgically excise or follow on imaging at 6-month intervals for a minimum of 2 years.
METHODS: Between May, 2015 and June, 2019, 127 high-risk lesions were discussed. Of these 127 cases, 116 had concordant radiology-pathology (rad-path) findings. The remaining 11 patients had discordant rad-path findings. Of the 116 concordant cases, 6 were excluded due to lack of the first imaging follow-up until analysis. Of the remaining 110 patients, 43 had atypical ductal hyperplasia (ADH), 12 had lobular carcinoma in situ (LCIS), 19 had atypical lobular hyperplasia (ALH), 33 had radial scar (RS), 2 had flat epithelial atypia (FEA), and 1 had mucocele-like lesion (ML). We recommended excision for ADH if there were > 2 ADH foci or < 90% of the associated calcifications were removed. For patients with LCIS or ALH, we recommended excision if the LCIS or ALH was associated with microcalcifications or the LCIS was extensive. We recommended excision of RS when < 1/2 of the lesion was biopsied. We recommended all patients with FEA and ML for 6-month follow-up.
RESULTS: Following conference-derived consensus for excision, of the 27 ADH excised, 9 were upgraded to invasive carcinoma or ductal carcinoma in situ. Of the six LCIS cases recommended for excision, none were upgraded. Nine excised radial scars revealed no upgrades. Additionally, 3 patients with ADH, 2 with ALH, 1 with LCIS, and 2 with RS underwent voluntary excision, and none were upgraded. All other patients (13 with ADH, 5 LCIS, 17 ALH, 22 RS, 2 FEA and 1 ML) were followed with imaging, and none revealed evidence of disease progression during follow-up (187-1389 days). All 11 rad-path discordant cases were excised with 2 upgraded to carcinoma.
CONCLUSIONS: The results of this prospective study indicate that high-risk breast lesions can be successfully triaged to surgery versus observation following establishment of predefined firm guidelines and performance of rigorous rad-path correlation.

Mucinous lesions of the breast include a variety of benign and malignant epithelial processes that display intracytoplasmic or extracellular mucin, including mucocelelike lesions, mucinous carcinoma, solid papillary carcinoma, and other rare subtypes of mucin-producing carcinoma. The most important diagnostic challenge is the finding of free-floating or stromal mucin accumulations for which the significance depends on the clinical, radiologic, and pathologic context. This article emphasizes the differential diagnosis between mucocelelike lesions and mucinous carcinoma, with a brief consideration of potential mimics, such as biphasic and mesenchymal lesions with myxoid stroma (\"stromal mucin\") and foreign material.

Many benign and reactive lesions of the breast show morphological overlap with malignant lesions. These benign mimics of malignancy often present diagnostic challenges to even the most experienced pathologists. This review focuses on several benign lesions of the breast that mimic malignant entities. For each of these lesions, we describe the key morphological and immunohistochemical features, potential diagnostic pitfalls, and our approach to arriving at the correct diagnosis.

Management of pure mucocele-like lesion (MLL) diagnosed on percutaneous breast biopsy (PBB) is controversial. To assess surgical upgrade rate and clinical outcome of pure MLL obtained as sole diagnosis on PBB. Patients diagnosed with a MLL as the most advanced lesion on PBB from April 1997 to December 2010 were reviewed for radiologic presentation, biopsy technique, and pathologic and clinical outcomes. Of the 21,340 image-guided PBB performed during the study period, 50 women with 51 MLL (0.24%) were identified. Mean age was 53.1 ± 7.7 years. Radiologic findings were mostly microcalcifications (n = 47, 92.2%). Stereotactic PBB was performed for 49 lesions (96.1%). Surgery was performed shortly after biopsy in 35 women, with benign final pathology in 33, and upgrade to ductal carcinoma in situ (DCIS) in two patients (2/35, 5.7%). Mean follow-up was 4.2 ± 2.5 years (3.7 ± 2.1 years for surgical patients; 5.9 ± 2.9 years for follow-up only patients); three women were lost to follow-up (3/50). Three invasive cancers (3/47, 6.4%) were diagnosed 1.2, 1.2, and 2.8 years after biopsy: two in surgical patients, and one in a follow-up only patient. No cancer occurred at the same site as the original MLL. Pure MLL lesion of the breast is a rare entity and is mostly associated with a benign outcome. We observed an upgrade to DCIS slightly superior to 5%, but no invasive cancer. It is therefore unclear if these lesions should be excised or clinically and radiologically followed up when such lesions are found at PBB.

OBJECTIVE: The purpose of this study was to determine the frequencies of atypia and cancer at excisional biopsy of lesions with a diagnosis of mucocele-like lesion (MLL) at percutaneous breast biopsy.
METHODS: Retrospective review of 9286 lesions subjected to percutaneous imaging-guided biopsy identified MLLs in 35 (0.38%) patients. Medical records, imaging studies, and histologic results were reviewed.
RESULTS: Of the 35 patients with core biopsy findings of MLL, 27 underwent stereotactic core needle biopsy (19 with microcalcifications, five with calcifications with an associated mass, and three with only a mass), and eight underwent ultrasound-guided core needle biopsy (four with a solid mass, three with a complex cystic mass). At core biopsy, 12 of 35 (34%) MLLs were associated with atypia (10 cases of atypical ductal hyperplasia, two of flat epithelial atypia), and 23 of 35 (66%) were benign MLL only. All 12 MLLs associated with atypia and 12 of 23 benign MLLs were surgically excised. Eleven patients did not undergo surgery, five of whom were lost to follow-up. One of the 12 (3% of the 35) MLLs associated with atypia was upgraded to DCIS. None were upgraded to invasive cancer. None of the benign MLLs were upgraded to malignancy, and findings at excision of four of the 23 (17%) benign MLLs led to a change in diagnosis to a high-risk lesion (three atypical ductal hyperplasia, one atypical lobular hyperplasia).
CONCLUSIONS: MLL is a rare diagnosis but is encountered in large-volume breast practices. The findings are nonspecific with a range of imaging appearances. No imaging test is reliable for differentiating MLL from other suspicious lesions or lesions with associated atypia. Surgery is clearly warranted for MLL associated with atypia at core needle biopsy because it may be upgraded to malignancy upon excision. However, if the presence of atypia at excision of benign MLL will change clinical management, then benign MLL at core needle biopsy warrants surgical excision in some cases. In patients whose treatment will not change if atypia is found at excision, close surveillance with short-interval follow-up is a reasonable alternative.