Clinical practice guidelines for molecular tumor marker, 2nd edition review part 2.

In recent years, rapid advancement in gene/protein analysis technology has resulted in target molecule identification that may be useful in cancer treatment. Therefore, "Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition" was published in Japan in September 2021. These guidelines were established to align the clinical usefulness of external diagnostic products with the evaluation criteria of the Pharmaceuticals and Medical Devices Agency. The guidelines were scoped for each tumor, and a clinical questionnaire was developed based on a serious clinical problem. This guideline was based on a careful review of the evidence obtained through a literature search, and recommendations were identified following the recommended grades of the Medical Information Network Distribution Services (Minds). Therefore, this guideline can be a tool for cancer treatment in clinical practice. We have already reported the review portion of "Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition" as Part 1. Here, we present the English version of each part of the Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition.

Characteristic Video Laryngeal Endoscopic "Pharyngeal Rotation" in Unilateral Pharyngeal Constrictor Muscle Paresis: A Case of Herpes Zoster Pharyngitis.

Herpes zoster pharyngitis (HZP) is a rare condition that should be considered as a differential diagnosis of acute dysphagia secondary to unilateral glossopharyngeal and/or vagal nerve palsy. Although early treatment is important to avoid adverse sequelae, serological diagnosis of varicella zoster virus (VZV) takes over a few days. Therefore, it is important to actively suspect VZV infection based on physical findings. Mucocutaneous lesions, curtain signs, and laryngeal palsy are well-known characteristic physical findings. In addition to these findings, the video laryngeal endoscopic finding that the pharyngeal constrictor muscles contract on only one side during swallowing, showing an appearance of "pharyngeal rotation", is one of the characteristic findings of glossopharyngeal/vagal nerve palsy and can support the diagnosis. We report the case of an 82-year-old Asian female who presented with acute dysphagia, sore throat, left ear pain, and fever that persisted for several days. Initial video laryngeal endoscopy revealed a markedly decreased pharyngeal reflex and significant salivary retention without mucosal vesicular lesions. Repeat videoendoscopic evaluation of swallowing revealed characteristic pharyngeal rotation, which was helpful in diagnosing unilateral pharyngeal constrictor muscle paresis, thus suggesting unilateral glossopharyngeal/vagal nerve palsy. An increase in serum antibody titers (IgG and IgM) against VZV was observed. Bilateral differences and rotation of the pharynx during pharyngeal contraction can be detected endoscopically in pharyngeal constrictor muscle paresis caused by glossopharyngeal/vagal nerve palsy and should be evaluated during video laryngeal endoscopy in patients with dysphagia.

Transvascular delivery of talaporfin sodium to subcutaneous tumors in mice by nanosecond pulsed laser-induced photomechanical waves.

BACKGROUND: We previously developed a site-specific transvascular drug delivery system (DDS) based on photomechanical waves (PMWs) or laser-induced stress/shock waves (LISWs). In this study, we investigated the validity of this method to deliver a clinical photosensitizer, talaporfin sodium (TS), to subcutaneous tumors in mice and to enhance the efficacy of photodynamic therapy (PDT). METHODS: TS solution (2.5 mg/kg) was intravenously injected into mice. Immediately thereafter, PMWs were applied to the tumor by irradiating a laser target with a Q-switched ruby laser pulse (0.8 J/cm2). Five hours after TS administration, some tumors were excised to evaluate the depth distribution of the delivered TS under a fluorescence microscope. Other tumors were subjected to PDT by irradiating the tissues with a 665 nm continuous-wave laser diode (75 mW/cm2, 667 s) at this timepoint. The effects of PDT were evaluated on the basis of the two primary therapeutic mechanisms of TS-mediated PDT: i) damage to tumor cells and ii) damage to endothelial cells of tumor vessels, i.e., the vascular shutdown effect on tumors. RESULTS: PMW application significantly increased the accumulation of TS in the tumor parenchyma but not in the tumor vessel walls; the endothelial cell junctions of tumor vessels should be the route of TS delivery enhanced by PMWs. Thus, as a result of PMW application followed by PDT, while the vascular shutdown effect on the tumors was not enhanced, direct damage to the tumor cells was increased, resulting in significant tumor growth retardation without body weight loss for 7 days after treatment.

Indications for sentinel lymph node biopsy in node-negative oral cancers.

BACKGROUND: We aimed to define the indications for sentinel lymph node biopsy (SLNB), the third option for cervical treatment in oral cancer with negative cervical lymph nodes. METHODS: The greatest depth of invasion (DOI) and long diameter (LD) of the primary site were used as exposures. SLN metastasis was considered the outcome. RESULTS: In three trials conducted between 2009 and 2016, 158 patients were eligible and reassigned to this study group. The scatterplot based on the respective values of DOI and LD would eventually be divided into three sections. In cases of sections T1, T2, and T3, the proportions of SLN metastasis positivity were 21.3%, 35.3%, and 51.2%, respectively. In certain cases of T1 with 2 mm < DOI ≤ 5 mm and 8 mm < LD ≤ 20 mm, the proportion of SLN metastasis positivity was 40.9%. CONCLUSIONS: SLNB-navigated or assisted neck dissection can be added as an effective procedure for N0 neck control.

Enhanced Therapeutic Effects of an Antitumor Agent on Subcutaneous Tumors in Mice by Photomechanical Wave-based Transvascular Drug Delivery.

Purpose: We previously developed a site-selective transvascular drug delivery system based on nanosecond pulsed laser-induced photomechanical waves (PMWs). In this study, we applied this method to the delivery of cisplatin (cis-diamminedichloroplatinum, CDDP) to a subcutaneous tumor in a mouse and examined its antitumor effects. Methods: A mouse tumor model with subcutaneous inoculation of human head and neck cancer cells (FaDu cells) was used. The mice were divided into four groups: control without any treatment (control), CDDP application only (CDDP only), PMW application only (PMW only) and combined application of PMWs and CDDP (PMW+CDDP). A PMW was generated by irradiating a laser target, which was placed on the skin over the tumor, with a ruby laser pulse (fluence, 1.6 J/cm2). A CDDP solution was intraperitoneally injected into the mice (2.5 mg/kg). Results: Until 7 days posttreatment, the tumor volume in the control group monotonically increased, while the tumor volumes in the CDDP-only group and PMW-only group did not change greatly and that in the PMW+CDDP group slightly decreased. Afterward, the tumors started to regrow in all treatment groups, but the tumor growth rate was considerably low in the PMW+CDDP group. There was a significant difference in the time courses of tumor volume between the PMW+CDDP group and the control group for up to 14 days posttreatment. The ratio of the Ki-67-positive (proliferative) areas to the whole tumor regions in the PMW+CDDP group was significantly smaller than that in the control group at 7 days posttreatment. These results are attributable to the synergistic effects of enhanced extravasation of CDDP and mechanical tumoricidal effect by PMWs. Conclusion: The combined application of CDDP and PMWs significantly improved the antitumor effects on mouse subcutaneous tumors.

Macroscopic and multiple metastases in sentinel lymph node biopsy are respectively associated with poor prognosis in early oral cancer.

BACKGROUND: A multicenter, randomized controlled phase III trial was conducted on sentinel lymph node biopsy (SLNB) and elective neck dissection for T1 (depth of invasion ≥ 4 mm)-T2N0M0 oral cavity squamous cell carcinoma. This study identified factors associated with poor prognosis in patients who underwent SLNB based on a subgroup analysis of this trial. METHODS: We analyzed 418 sentinel lymph nodes (SLNs) from 132 patients who underwent SLNB. The metastatic SLNs were classified into three categories based on size-isolated tumor cells: < 0.2 mm, micrometastasis: ≥ 0.2 mm and < 2 mm, and macrometastasis: ≥ 2 mm. Three groups were formed based on the number of metastatic SLNs: no metastasis, 1 metastatic node, and ≥ 2 metastatic nodes. The size and number of metastatic SLNs on survival were evaluated using Cox proportional hazard models. RESULTS: Patients with macrometastasis and ≥ 2 metastatic SLNs had worse overall survival (OS) and disease-free survival (DFS) after adjustment for potential confounders (HR for OS: macrometastasis, 4.85; 95% CI 1.34-17.60; ≥ 2 metastatic SLN, 3.63; 95% CI 1.02-12.89; HR for DFS: macrometastasis, 2.94; 95% CI 1.16-7.44; ≥ 2 metastatic SLN, 2.97; 95% CI 1.18-7.51). CONCLUSIONS: In patients who underwent SLNB, a poorer prognosis was associated with macrometastasis or having ≥ 2 metastatic SLNs.

The value of serum p53 antibody as a biomarker in oral and pharyngeal squamous cell carcinoma.

BACKGROUND: The development of more sensitive biomarkers for the detection of early-stage head and neck squamous cell carcinoma is needed. AIMS/OBJECTIVES: This study was performed to assess the value of serum p53 antibody (s-p53-Ab) as a biomarker for oral and pharyngeal carcinoma. MATERIAL AND METHODS: Pre-treatment serum was collected for 71 patients with oral and pharyngeal carcinoma and 117 healthy volunteers as controls and analyzed s-p53-Ab using enzyme-linked immunosorbent assay (ELISA). RESULTS: Using 1.3 U/mL as the cut-off value, 14 of 71 patients (sensitivity 19.7%), and 12 of 117 control cases were positive for s-p53-Ab (specificity 89.7%). Excluding 12 cases of p16-positive oropharyngeal and nasopharyngeal cancer which were all negative for s-p53-Ab, the sensitivity in early-stage 1-2 cases was 30.0%, which was higher than conventional tumor markers. CONCLUSIONS AND SIGNIFICANCE: The s-p53-Ab was not detected in any cases of virus-related cancer in which p53 gene mutations were not involved in carcinogenesis. Since the s-p53-Ab sensitivity was high even in early-stage disease, s-p53-Ab measurement may be useful as an early diagnostic biomarker in patients with oral, p16- oropharyngeal, and hypopharyngeal cancer.

Evaluation of chronological changes in videofluorographic findings after transoral videolaryngoscopic surgery to reveal mechanism of dysphagia.

OBJECTIVES: Transoral surgery preserves good swallowing function in most cases, however, postoperative dysphagia sometimes leads to fatal complication such as aspiration pneumonia. We investigated the chronological changes in swallowing function have not been revealed relationship with dysphagia. The primary aim of this study was to reveal the mechanism of dysphagia following transoral surgery by analyzing chronological videofluorography (VF) findings. Moreover, the secondary aim of this study was to evaluate the relationship between mechanism of dysphagia and risk factors of patients to clarify the risk for dysphagia lead to prevention of postoperative complications. METHODS: 22 patients who underwent transoral videolaryngoscopic surgery (TOVS) for either supraglottic or hypopharyngeal cancer were evaluated swallowing function. We performed VF during the preoperative, postoperative acute, and stable phases and investigated the chronological changes in the VF findings. The following parameters were evaluated by VF: horizontal distance of laryngeal movement, vertical distance of laryngeal elevation, laryngeal elevation delay time (LEDT), Bolus Residue Scale (BRS) scores, and Penetration Aspiration Scale (PAS) scores. Additionally, we evaluated risk factors for postoperative aspiration by investigating relationships between preoperative VF parameters, age of patients, history of radiation therapy, resection area, tumor (T) stage, postoperative Numeric Rating Scale (NRS), and PAS and BRS scores. RESULTS: The median time at which oral feeding was resumed in this study was 9 (2-200) days. The patients who had postoperative acute PAS scores of 4 and above exhibited delays in resuming oral ingestion after surgery. TOVS did not impair laryngeal elevation and LEDT; however, the BRS and PAS scores temporarily worsened in the acute phase compared to the preoperative scores. These scores almost recovered to their preoperative states in the stable phase, and both the BRS and PAS scores worsened and recovered concurrently. Patients who exhibited poor vertical distance in laryngeal elevation as observed via preoperative VF or who had histories of radiation therapy had worse PAS scores in postoperative acute phase VF. Patients with broad resection areas had worse BRS scores in postoperative acute phase VF. CONCLUSION: TOVS didn't impair the function of laryngeal elevation and elicitation of the swallowing reflex whereas pharyngeal bolus clearance, laryngeal penetration, and aspiration temporarily deteriorated concurrently but eventually almost recovered to their baseline values. Patients with histories of radiotherapy, poor laryngeal elevation, and broad resection areas are at the risk of postoperative dysphagia after TOVS. Patients with these risk factors need appropriate evaluation before resuming postoperative oral intake.

A Case of Pancreatic Metastasis From Small Cell Neuroendocrine Carcinoma of the Oropharynx.

Small cell neuroendocrine carcinoma (SNEC) rarely occurs in the head and neck and usually occurs in the lungs. We report the case of a 55-year-old Asian male with SNEC in the oropharynx and jaundice due to pancreatic metastasis, which was successfully palliated by amrubicin (AMR), radiotherapy, and an endoscopic biliary stent. Although pancreatic metastases are known to occur at the end stage of small cell lung cancer, there are limited data on the treatment protocols for pancreatic metastases from SNEC. The main complication of SNEC for pancreatic lesions is obstructive jaundice. Palliative radiotherapy and biliary drainage may have life-prolonging effects in patients with extrahepatic biliary obstruction. It may also be a worthwhile risk to use anticancer drugs, such as AMR that are metabolized in the liver, if the obstructive jaundice is caused by tumor growth.

First description of Lachnoanaerobaculum orale as a possible cause of human bacteremia.

Lachnoanaerobaculum spp. is an obligate anaerobic, gram-positive, spore-forming, rod-shaped bacillus. Here, we report the first known case of bacteremia due to L. orale, which was detected in a patient with acute lymphoblastic leukemia. A 69-year-old man developed neutropenic fever with severe stomatitis during chemotherapy for leukemia. The bacteria strain isolated from blood culture was successfully identified as L. orale via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Susceptibility testing revealed that the strains showed low minimum inhibitory concentrations (MICs) of beta-lactams, clindamycin, and metronidazole, but higher MICs of fluoroquinolones. The present case study indicates that Lachnoanaerobaculum can be a cause of human infection, including bloodstream infection.

Inhibition of extracellular signal-regulated kinase pathway suppresses tracheal stenosis in a novel mouse model.

Tracheal stenosis is a refractory and recurrent disease induced by excessive cell proliferation within the restricted tracheal space. We investigated the role of extracellular signal-regulated kinase (ERK), which mediates a broad range of intracellular signal transduction processes in tracheal stenosis and the therapeutic effect of the MEK inhibitor which is the upstream kinase of ERK. We histologically analyzed cauterized tracheas to evaluate stenosis using a tracheal stenosis mouse model. Using Western blot, we analyzed the phosphorylation rate of ERK1/2 after cauterization with or without MEK inhibitor. MEK inhibitor was intraperitoneally injected 30 min prior to cauterization (single treatment) or 30 min prior to and 24, 48, 72, and 96 hours after cauterization (daily treatment). We compared the stenosis of non-inhibitor treatment, single treatment, and daily treatment group. We successfully established a novel mouse model of tracheal stenosis. The cauterized trachea increased the rate of stenosis compared with the normal control trachea. The phosphorylation rate of ERK1 and ERK2 was significantly increased at 5 min after the cauterization compared with the normal controls. After 5 min, the rates decreased over time. The daily treatment group had suppressed stenosis compared with the non-inhibitor treatment group. p-ERK1/2 activation after cauterization could play an important role in the tracheal wound healing process. Consecutive inhibition of ERK phosphorylation is a potentially useful therapeutic strategy for tracheal stenosis.

Clinical Surveillance of Candidemia at Our Hospital.

Treatment of Candidemia has become increasingly complicated as more and more non-albicans Candida species are being isolated in recent years.We launched an investigation of the species, the MIC value, and the state of administration of antifungal drugs for all the cases with Candida spp. confirmed by blood cultures for the 7-year period from 2012 to 2018 at our hospital. In total, 192 cases were found and 206 strains of Candida species were isolated. Overall, 49.5% of the 206 isolated strains were Candida albicans (102 strains), followed by Candida glabrata (40 strains, 19.4%), and Candida parapsilosis (38 strains, 18.4%). The most frequently used antifungal drug for the initial dose was MCFG (120 cases, 59.2%), while the most frequently switched antifungal agent was L-AMB. Cases with an inappropriate end-of-treatment time represented 58.7% of all the cases.We investigated the Candidemia situation at our hospital for a period of seven years. We believe that it is important for medical institutions to gather detailed data on candidemia at their own hospitals. Likewise, the hospital's Infection Control Team/Antimicrobial Stewardship Team should inform the physicians-in-charge about the appropriate diagnosis and treatment based on the data obtained.

A case of infective endocarditis caused by "Neisseria skkuensis".

"Neisseria skkuensis" is a gram-negative coccus that is endemic in the human oral cavity, with only few reports of infection in humans. Herein, we report a case of a male patient in his sixties presenting with infective endocarditis (IE) caused by "N. skkuensis". To our knowledge, this is the second case of IE confirmed using 16S rRNA gene to have been caused by "N. skkuensis". The accurate diagnosis of rare or difficult-to-identify pathogens is a major challenge for clinical microbiological laboratories. Although Neisseria spp. are common in the oral cavity and are often seen in routine tests, identification of their biochemical properties and mass spectrometric analysis are difficult. In this case report, we describe the accurate identification of "N. skkuensis" by 16S rRNA gene sequencing analysis compared to other identification methods. Further cases of "N. skkuensis" are needed to fully evaluate the clinical approach of this detection method.

TrkA inhibitor promotes motor functional regeneration of recurrent laryngeal nerve by suppression of sensory nerve regeneration.

Recurrent laryngeal nerve (RLN) injury, in which hoarseness and dysphagia arise as a result of impaired vocal fold movement, is a serious complication. Misdirected regeneration is an issue for functional regeneration. In this study, we demonstrated the effect of TrkA inhibitors, which blocks the NGF-TrkA pathway that acts on the sensory/automatic nerves thus preventing misdirected regeneration among motor and sensory nerves, and thereby promoting the regeneration of motor neurons to achieve functional recovery. RLN axotomy rat models were used in this study, in which cut ends of the nerve were bridged with polyglycolic acid-collagen tube with and without TrkA inhibitor (TrkAi) infiltration. Our study revealed significant improvement in motor nerve fiber regeneration and function, in assessment of vocal fold movement, myelinated nerve regeneration, compound muscle action potential, and prevention of laryngeal muscle atrophy. Retrograde labeling demonstrated fewer labeled neurons in the vagus ganglion, which confirmed reduced misdirected regeneration among motor and sensory fibers, and a change in distribution of the labeled neurons in the nucleus ambiguus. Our study demonstrated that TrkAi have a strong potential for clinical application in the treatment of RLN injury.

Scar contracture prevention with local steroid injections in transoral videolaryngoscopic surgery.

OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of local steroid injections to prevent scar contracture after transoral videolaryngoscopic surgery (TOVS) in hypopharyngeal cancer patients. METHODS: Patients were enrolled in this study if they had received a local steroid injection during TOVS and had attended an outpatient clinic after at least three months. All patients were being treated for hypopharyngeal cancer and received a single session of triamcinolone acetonide, injected using a 21-gage needle. Retrospective chart reviews were performed, and the degree of scar contracture, pharyngeal stenosis, vocal fold movements, and adverse events were evaluated. Scar contracture was assessed using a scoring system, which compared the endoscopic findings of treatment and matched pair control groups. RESULTS: A total of 20 patients received local steroid injections during TOVS and were enrolled in the treatment. Scar contracture was seen in 14 patients (70%); however, the degree of scar contracture was significantly decreased when compared to control cases. Vocal fold immobility was observed in five patients, but no pharyngeal stenosis was noted. Adverse effects, such as postoperative laryngeal chondritis or cervical spondylitis, were seen in three patients who had previously been treated with resection to the muscularis propria or definitive irradiation. CONCLUSION: Local steroid injection during TOVS significantly reduced the degree of postoperative scar contracture. However, caution should be used when treating with local steroid injection during TOVS, as this may complicate wound healing in patients who have already received treatment.

Transoral videolaryngoscopic surgery for laryngeal and hypopharyngeal cancer - Technical updates and long-term results.

OBJECTIVE: Transoral videolaryngoscopic surgery (TOVS) was developed as a non-robotic procedure for en bloc laryngo-hypopharyngeal cancer resection. Straight devices had been used for this procedure, however, some cases had difficulty to reach the lesions especially in hypopharyngeal area. To overcome this problem, technical updates to facilitate transoral manipulation were developed and long term oncological and functional results were analyzed. METHODS: Surgical indications were Tis, T1, T2 and selected T3 cases. In advanced T3 or T4 lesions, neoadjuvant chemotherapy was performed before surgery. Radiation failure cases (rT1 and rT2) were also indicated for TOVS. Resectable nodal involvement can be managed by combination of neck dissection. Ninety hypopharyngeal and 25 supraglottic cancer cases were retrospectively reviewed for survival analyses. In fresh hypopharyngeal cancer, 51 Stage 0-II disease and 32 Stage III-IV disease were included. In supraglottic cancer, 11 Stage I-II disease and 9 Stage III-IV disease were included. Twelve radiation failure cases were analyzed separately. As new devices, malleable forceps and malleable suction coagulator were introduced to reach the whole laryngo-hypopharynx. New curved blades for the FKWO retractor were developed and these were applied for difficult hypopharyngeal exposure cases by conventional blades. Swallowing functional outcome and risk factors for postoperative dysphagia were evaluated by univariate analysis. RESULTS: The 5-year overall survival, disease-specific survival and larynx preservation rate of fresh hypopharyngeal cancer cases were 83.2%, 94.3% and 94.6%, respectively. Those of supraglottic cancer cases were 80%, 95% and 94.7%, respectively. Those of salvage cases were 87.5%, 87.5% and 82.5%, respectively. Those of T3 and T4 hypopharyngeal cancer treated by neoadjuvant chemotherapy with TOVS were 75.0%, 82.5% and 100% respectively. Surgical complication included bleeding (2.6%) and emergency tracheostomy (3.4%). Oral intake was maintained in 94.8% cases. By univariate analysis, patient's age (especially 80 years of age or older), larger resected area, arytenoid resection and tracheostomy were regarded as risk factors for postoperative dysphagia. Among 31 recent cases, 5 cases had difficulty in exposing hypopharyngeal lesions by conventional blades. These exposure problems were solved by curved blades. CONCLUSION: Using malleable devices and new curved blades for the FKWO retractor, exposure problems in the hypopharynx could be solved and TOVS could be applied in more cases. Although oncological outcomes and functional outcomes were good, patients with risk factors for dysphagia should be carefully indicated.

Minimally invasive surgery for laryngopharyngeal cancer: Multicenter feasibility study of a combination strategy involving transoral surgery and real-time indocyanine green fluorescence-navigated sentinel node navigation surgery.

BACKGROUND: Sentinel node navigation surgery using indocyanine green (ICG-SNNS) can be performed in the operation room. The combination of minimally invasive transoral surgery (TOS) with ICG-SNNS can provide functional preservation options for both primary lesions and lymph node (LN) metastasis. This multicenter feasibility study of this strategy was conducted in Japan. METHODS: Patients with clinical T1 or T2, N0 oropharyngeal, hypopharyngeal, or supraglottic cancer were enrolled. The identification rate of sentinel nodes, delayed cervical LN metastasis in 2 years, and survival rate were assessed. RESULTS: Twenty-two patients (10 oropharynx, 8 hypopharynx, 4 supraglottic cancer) were enrolled. The identification rate was 100%. One case had delayed nodal metastasis. The accuracy was 95.5%, sensitivity was 75%, and specificity was 100%. The 5-year disease-specific survival was 100%, overall survival was 72.3%, and disease-free survival was 60.5%. CONCLUSIONS: The combination of TOS with ICG-SNNS is feasible as a minimally invasive strategy and has favorable oncological outcomes.

Skin and Soft Tissue Infections Caused by Different Genotypes of PVL-Positive Community-Acquired Methicillin-Resistant Staphylococcus aureus Strains.

Panton-Valentine leukocidin (PVL) is a causative agent of lethal necrotizing pneumonia and is associated with epidemic strains of community-acquired (CA) methicillin-resistant Staphylococcus aureus (MRSA). PVL-producing strains have rarely been isolated in Japan. However, PVL-positive CA-MRSA has been isolated much more frequently in recent years. To investigate the relevance of pvl genes (lukS/F-PV) and clinical traits in epidemic S. aureus strains, we genotyped four PVL-positive CA-MRSA strains isolated from patients with skin and soft tissue infections and measured their susceptibility to antibiotics. Three of the isolates matched the genotype of the USA300 clone, which has predominantly been isolated in the USA. The remaining strain matched the ST217 genotype, and its spa type was identical to that of PVL-positive strains previously reported in India and China. Abscess drainage was necessary in all cases, and deep cutaneous ulcers were formed in three out of four cases regardless of the genotype. The ST217 genotype strain was resistant to clindamycin, in addition to quinolones, macrolides, and aminoglycosides. Thus, diagnostic determination of lukS/F-PV should be used as a guide for selecting the treatment regimen.