MicroRNAs (miRs) are expected to serve as prognostic tools for cancer. However, many miRs have been reported as prognostic markers of recurrence or metastasis in oral squamous cell carcinoma patients. We aimed to determine the prognostic markers in early-stage tongue squamous cell carcinoma (TSCC). Based on previous studies, we hypothesized that miR-10a, 10b, 196a-5p, 196a-3p, and 196b were prognostic markers and we retrospectively performed miR expression analyses using formalin-fixed paraffin-embedded sections of surgical specimens. Total RNA was isolated from cancer tissues and adjacent normal tissue as control, and samples were collected by laser-capture microdissection. After cDNA synthesis, reverse transcription-quantitative polymerase chain reaction was performed. Statistical analyses for patient clinicopathological characteristics, recurrence/metastasis, and survival rates were performed to discern their relationships with miR expression levels, and the 2−ΔΔCq method was used. miR-196a-5p levels were significantly upregulated in early-stage TSCC, particularly in the lymph node metastasis (LNM) group. The LNM-free survival rate in the low miR-196a-5p ΔΔCq value regulation group was found to be lower than that in the high ΔΔCq value regulation group (P=0.0079). Receiver operating characteristic analysis of ΔΔCq values revealed that miR-196a-5p had a P-value=0.0025, area under the curve=0.740, and a cut-off value=−0.875 for distinguishing LNM. To our knowledge, this is the first study to examine LNM-related miRs in early-stage TSCC as well as miRs and ‘delayed LNM’ in head and neck cancer. miR-196a-5p upregulation may predict delayed LNM. Our data serve as a foundation for future studies to evaluate miR levels and facilitate the prediction of delayed LNM during early-stage TSCC, which prevent metastasis when combined with close follow-up and aggressive adjuvant therapy or elective neck dissection. Moreover, our data will serve as a foundation for future studies to evaluate whether miR-196a-5p can serve as a therapeutic marker for preventing metastasis.

Low-grade myofibroblastic sarcoma (LGMS) is a neoplasm of the soft tissue characterized by myofibroblastic differentiation. This type of tumor has been observed in various sites in the whole body, but frequently occurs in the head and neck region. It typically presents as a slow-growing painless mass, which is often mistaken for a benign lesion due to its indolent growth; however, LGMS is a malignant neoplasm. In the present study, a 43-year-old female presented with a 14-mm LGMS lesion in the buccal subcutaneous tissues of the buccinator muscle. The patient had initially noticed the lesion 2-months prior to presenting at the hospital. Following biopsy, the tumor was surgically resected and no recurrence or metastasis was observed during a follow-up time of 2 years. To the best of our knowledge, this case is the first report of LGMS located in the buccal subcutaneous tissue of the buccinator muscle. The present study a literature review of 55 cases of this tumor type in the head and neck region was conducted, revealing that the indolent growth of these lesions may contribute to a delay in diagnosis. The average time between the onset of clinical symptoms and hospital admission is 3.9 months, and this form of tumor is frequently misdiagnosed as a benign lesion. Therefore, the present study suggests that an incisional biopsy may be performed to rule out LGMS when clinicians encounter patients with the aforementioned indolent lesions anywhere in the body. In addition, the avoidance of radiotherapy is recommended following resection of the LGMS tumor, as it may induce LGMS recurrence.

Dedifferentiated liposarcoma (DDLS) has a relatively poor prognosis, however this neoplasm rarely occurs in the head and neck. To date, no definite protocol has been established for the diagnosis and treatment of head and neck DDLS. The present study reports the case of a 69-year-old male patient with DDLS of the oral floor. To the best of our knowledge, this is the first documented case of oral floor DDLS. In addition, this is the first reported case with the development of a second primary malignancy following the treatment of head and neck DDLS. A literature review of 50 cases of head and neck DDLS revealed that preoperative biopsy is not reliable for the diagnosis of these tumors and an accurate pathological diagnosis with total resection is preferred.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare self-limiting disorder typically affecting the cervical lymph nodes (LNs), which is often misdiagnosed as other LN-associated diseases. KFD frequently presents with necrotic lesions and recurrences, which are also features of metastatic LNs. Clinicians may thus suspect LN metastasis when they encounter ipsilateral cervical lymphadenopathy in a patient with head and neck cancer. The present study reports the case of a 48-year-old man with tongue cancer and KFD affecting the right edge of his tongue and ipsilateral cervical LNs. LN metastasis was initially suspected, but pathological examination of the dissected LNs revealed one necrotic metastatic lesion and two necrotic KFD lesions. Ipsilateral cervical lymphadenopathy recurred 6 years after the initial surgery, and it was not possible to differentiate clinically between a second primary tumor and recurrent KFD prior to treatment. To the best of our knowledge, this is the first reported case of simultaneous tongue cancer, regional LN metastasis and KFD. This highlights the requirement to consider KFD in the event of LNs with necrotic lesions but no cancerous cells. A combination of clinical and pathological approaches may aid in the diagnosis of KFD, in addition to ruling out LN metastasis in initial and recurrent lymphadenopathies. The present study indicate that a diagnosis of KFD should be considered in patients with head and neck cancer that exhibit necrotic LNs lacking cancerous cells. This is important, as misdiagnosis of KFD as LN metastasis may lead to unnecessary adjuvant therapy.

Monocytes express on the cell surface several kinds of chemokine receptors that facilitate chemotaxis followed by differentiation in target tissues. In the present study, we found that a large number of monocytes from peripheral blood mononuclear cells (PBMCs) tightly adhered to plastic cell culture plates precoated with a monoclonal antibody (mAb, clone T312) specific for human CCR5 but not an isotype control after overnight incubation. Soluble T312 did not induce such adhesion, indicating that cross-linking of CCR5 is required for the enhanced adhesion of monocytes. The adhesion was blocked by a PI3-K inhibitor and an anti-CD18 blocking mAb. Following the cross-linking of CCR5, monocytes synthesized high levels of M-CSF, RANTES, MIP-1 alpha, and MIP-1 beta associated with a readily detectable down modulation of CD14, CD4, CCR5, and CXCR4 expression. The T312-enriched monocytes differentiated into dendritic cells (DCs) in the presence of interleukin-4 alone. After maturation with beta-interferon, the T312-induced DCs stimulated proliferation of allogeneic naïve CD4(+) T cells accompanied by the synthesis of high levels of gamma-interferon in vitro. Furthermore, the T312-induced DCs were capable of stimulating antigen-specific human T- and B-cell immune responses in our hu-PBL-SCID mouse system. Finally, screening of other anti-chemokine receptor mAbs showed that select clones of mAbs against CXCR4 and CCR3 were also capable of facilitating enrichment of monocytes similar to T312. These results show that cross-linking of chemokine receptors on monocytes by appropriate mAbs leads to activation and differentiation of monocytes and that the method described herein provides an alternate simple strategy for adherence-based isolation of monocytes and generation of functional DCs.