Gene-specific somatic epigenetic mosaicism of FDFT1 underlies a non-hereditary localized form of porokeratosis.

Porokeratosis is a clonal keratinization disorder characterized by solitary, linearly arranged, or generally distributed multiple skin lesions. Previous studies showed that genetic alterations in MVK, PMVK, MVD, or FDPS-genes in the mevalonate pathway-cause hereditary porokeratosis, with skin lesions harboring germline and lesion-specific somatic variants on opposite alleles. Here, we identified non-hereditary porokeratosis associated with epigenetic silencing of FDFT1, another gene in the mevalonate pathway. Skin lesions of the generalized form had germline and lesion-specific somatic variants on opposite alleles in FDFT1, representing FDFT1-associated hereditary porokeratosis identified in this study. Conversely, lesions of the solitary or linearly arranged localized form had somatic bi-allelic promoter hypermethylation or mono-allelic promoter hypermethylation with somatic genetic alterations on opposite alleles in FDFT1, indicating non-hereditary porokeratosis. FDFT1 localization was uniformly diminished within the lesions, and lesion-derived keratinocytes showed cholesterol dependence for cell growth and altered expression of genes related to cell-cycle and epidermal development, confirming that lesions form by clonal expansion of FDFT1-deficient keratinocytes. In some individuals with the localized form, gene-specific promoter hypermethylation of FDFT1 was detected in morphologically normal epidermis adjacent to methylation-related lesions but not distal to these lesions, suggesting that asymptomatic somatic epigenetic mosaicism of FDFT1 predisposes certain skin areas to the disease. Finally, consistent with its genetic etiology, topical statin treatment ameliorated lesions in FDFT1-deficient porokeratosis. In conclusion, we identified bi-allelic genetic and/or epigenetic alterations of FDFT1 as a cause of porokeratosis and shed light on the pathogenesis of skin mosaicism involving clonal expansion of epigenetically altered cells.

Identification of a rare MET variant in a familial case of extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is an intraepithelial adenocarcinoma that primarily affects the genital and axillary areas in elderly individuals. A limited number of paired familial EMPD cases (i.e., parent-offspring, siblings) have been reported, whereas the genetics of these cases have not yet been adequately studied. We report the first familial case of EMPD involving three affected siblings. The tumour-only multi-gene panel testing using surgical specimens revealed a heterozygous c.2997A>C (p.Glu999Asp) nonsynonymous variant in the proto-oncogene MET (NM_000245.4) in the three affected siblings. The germline multi-gene panel testing using peripheral blood lymphocytes revealed the same missense MET variant in all five family members, including the two asymptomatic offspring (51 and 37 years of age). The MET variant we identified could be involved in EMPD carcinogenesis. Further genomic analyses of familial cases of EMPD are warranted to validate the pathogenic relevance of MET variants in EMPD development.

Eribulin for patients with metastatic extramammary Paget disease: Study protocol for a single-arm phase II trial.

Extramammary Paget disease (EMPD) is a rare cutaneous malignancy that predominantly affects the anogenital areas of the elderly. Although the efficacy of docetaxel and other cytotoxic agents for advanced EMPD has been reported in small retrospective case studies, no treatment has been proven effective in prospective clinical trials. We established the world's first in vivo EMPD experimental model (a patient-derived xenograft model). In our treatment experiment, xenograft tumours showed a remarkable response to eribulin. This study evaluates the efficacy of eribulin for patients with advanced EMPD. In October 2022, we started a single-arm phase II trial to evaluate the efficacy of eribulin as a treatment for adult patients with unresectable EMPD with measurable lesions. Enrolment in this clinical trial is open to patients with any prior treatment for EMPD. The primary endpoint is overall response rate; the secondary endpoints include disease control rate, overall survival, progression-free survival and adverse events. The study protocol was approved by the Ethics Committee of Hokkaido University and the other collaborating institutions. If the primary endpoint is met, it is our hope that eribulin will be regarded as a standard medication for patients with advanced EMPD.

Pre-existing Interstitial Lung Abnormalities and Immune Checkpoint Inhibitor-Related Pneumonitis in Solid Tumors: A Retrospective Analysis.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have demonstrated efficacy over previous cytotoxic chemotherapies in clinical trials among various tumors. Despite their favorable outcomes, they are associated with a unique set of toxicities termed as immune-related adverse events (irAEs). Among the toxicities, ICI-related pneumonitis has poor outcomes with little understanding of its risk factors. This retrospective study aimed to investigate whether pre-existing interstitial lung abnormality (ILA) is a potential risk factor for ICI-related pneumonitis. MATERIALS AND METHODS: Patients with non-small cell lung cancer, malignant melanoma, renal cell carcinoma, and gastric cancer, who was administered either nivolumab, pembrolizumab, or atezolizumab between September 2014 and January 2019 were retrospectively reviewed. Information on baseline characteristics, computed tomography findings before administration of ICIs, clinical outcomes, and irAEs were collected from their medical records. Pre-existing ILA was categorized based on previous studies. RESULTS: Two-hundred-nine patients with a median age of 68 years were included and 23 (11.0%) developed ICI-related pneumonitis. While smoking history and ICI agents were associated with ICI-related pneumonitis (P = .005 and .044, respectively), the categories of ILA were not associated with ICI-related pneumonitis (P = .428). None of the features of lung abnormalities were also associated with ICI-related pneumonitis. Multivariate logistic analysis indicated that smoking history was the only significant predictor of ICI-related pneumonitis (P = .028). CONCLUSION: This retrospective study did not demonstrate statistically significant association between pre-existing ILA and ICI-related pneumonitis, nor an association between radiologic features of ILA and ICI-related pneumonitis. Smoking history was independently associated with ICI-related pneumonitis. Further research is warranted for further understanding of the risk factors of ICI-related pneumonitis.

Role of androgen signaling in androgen receptor-positive extramammary Paget's disease: Establishment of organoids and their biological analysis as a novel therapeutic target.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare intraepithelial adenocarcinoma that mainly affects the anogenital and axillary regions. Although its etiology has not been fully elucidated, there is evidence that androgen receptors (AR) are expressed in most cases of EMPD. However, the role of androgen signaling in the pathogenesis of EMPD remains unclear. OBJECTIVE: To evaluate the role of androgen signaling in tumor growth of AR-positive EMPD. METHODS: Patient-derived organoids were established and cultured from two AR-positive EMPD patients: one man and one woman. Cultured organoids were treated with androgen agonists and/or antagonists, then subjected to analysis of changes in organoid proliferation, as well as changes in androgen signaling pathway-specific genes. RESULTS: Organoid cultures were established from each EMPD sample. These organoids were immunohistologically and genetically identical to the original tumor. For each organoid sample, viable cell number increased in response to androgen exposure. The mRNA level of Fkbp5, a known AR target gene, increased in a concentration-dependent manner in organoids exposed to the synthetic androgen R1881. Conversely, the AR inhibitor darolutamide suppressed the viable cell number in a concentration-dependent manner. The mRNA expression levels of MKI67 and Fkbp5 were also suppressed by darolutamide. CONCLUSION: Our results indicate that androgen signaling is a key pathway involved in the growth of AR-positive EMPD. Therefore, androgen signaling inhibition may be a novel treatment option for EMPD patients who require systemic therapy.

Integrated analysis of phase 1a and 1b randomized controlled trials; Treg-targeted cancer immunotherapy with the humanized anti-CCR4 antibody, KW-0761, for advanced solid tumors.

INTRODUCTION: Regulatory T cells (Tregs) have attracted attention as a novel therapeutic target to augment the clinical efficacy of immunotherapy. We conducted phase Ia and Ib trials to examine the safety and efficacy of the anti-CCR4 antibody, KW-0761 (mogamulizumab), which may eliminate effector Tregs (eTregs). We herein overviewed the results of these trials, presented cases with a durable clinical response, and investigated factors associated with the clinical effects of KW-0761. METHODS: Forty-nine patients with CCR4-negative solid cancers were enrolled in the phase Ia and Ib trials on KW-0761. An integral analysis of safety, clinical responses, prognosis, blood laboratory data, and cancer testis antigen-specific immune responses was performed. RESULTS: Grade 3-4 treatment-related adverse events were reported in 21 (42.9%) out of 49 patients, all of which were manageable. A partial response and stable disease were observed in 1 and 9 patients, respectively. A durable clinical response was noted in 2 esophageal and 2 lung cancer patients. eTreg depletion in peripheral blood was confirmed in most patients, and eTreg depletion was sustained during the KW-0761 treatment. High lymphocyte levels at baseline and 2 weeks after the initiation of KW-0761 were associated with a favorable clinical outcome. CONCLUSIONS: A durable clinical response was noted in some patients, and high lymphocyte levels before treatment initiation may be a biomarker for the efficacy of KW-0761. The synergistic effect of KW-0761 for depleting Tregs and other immunotherapies is expected in the future.

Systemic therapy for Asian patients with advanced BRAF V600-mutant melanoma in a real-world setting: A multi-center retrospective study in Japan (B-CHECK-RWD study).

BACKGROUND: Anti-PD-1-based immunotherapy is considered a preferred first-line treatment for advanced BRAF V600-mutant melanoma. However, a recent international multi-center study suggested that the efficacy of immunotherapy is poorer in Asian patients in the non-acral cutaneous subtype. We hypothesized that the optimal first-line treatment for Asian patients may be different. METHODS: We retrospectively collected data of Asian patients with advanced BRAF V600-mutant melanoma treated with first-line BRAF/MEK inhibitors (BRAF/MEKi), anti-PD-1 monotherapy (Anti-PD-1), and nivolumab plus ipilimumab (PD-1/CTLA-4) between 2016 and 2021 from 28 institutions in Japan. RESULTS: We identified 336 patients treated with BRAF/MEKi (n = 236), Anti-PD-1 (n = 64) and PD-1/CTLA-4 (n = 36). The median follow-up duration was 19.9 months for all patients and 28.6 months for the 184 pa tients who were alive at their last follow-up. For patients treated with BRAF/MEKi, anti-PD-1, PD-1/CTLA-4, the median ages at baseline were 62, 62, and 53 years (p = 0.03); objective response rates were 69%, 27%, and 28% (p < 0.001); median progression-free survival (PFS) was 14.7, 5.4, and 5.8 months (p = 0.003), and median overall survival (OS) was 34.6, 37.0 months, and not reached, respectively (p = 0.535). In multivariable analysis, hazard ratios (HRs) for PFS of Anti-PD-1 and PD-1/CTLA-4 compared with BRAF/MEKi were 2.30 (p < 0.001) and 1.38 (p = 0.147), and for OS, HRs were 1.37 (p = 0.111) and 0.56 (p = 0.075), respectively. In propensity-score matching, BRAF/MEKi showed a tendency for longer PFS and equivalent OS with PD-1/CTLA-4 (HRs for PD-1/CTLA-4 were 1.78 [p = 0.149]) and 1.03 [p = 0.953], respectively). For patients who received second-line treatment, BRAF/MEKi followed by PD-1/CTLA-4 showed poor survival outcomes. CONCLUSIONS: The superiority of PD-1/CTLA-4 over BRAF/MEKi appears modest in Asian patients. First-line BRAF/MEKi remains feasible, but it is difficult to salvage at progression. Ethnicity should be considered when selecting systemic therapies until personalized biomarkers are available in daily practice. Further studies are needed to establish the optimal treatment sequence for Asian patients.

Clinicopathological significance of androgen receptor expression in extramammary Paget disease: An analysis of 92 patients.

Extramammary Paget disease (EMPD) is a rare cutaneous malignant neoplasm arising in apocrine gland-rich areas. Although - like normal apocrine glands - EMPD frequently expresses androgen receptor (AR), the clinical significance of AR expression remains unclear. The present study investigated the clinicopathological impact of AR expression in EMPD. Immunohistochemistry for AR was performed in a retrospective cohort of 92 EMPD patients with 108 EMPD lesions, including 102 primary lesions, five lymph node [LN] metastases and one local recurrence. The total AR staining score was calculated as staining intensity score (IS 0-3) × positive-cell percentage score (PS 1-4). Expression levels were graded as Grade 1 (scores 0 and 1), Grade 2 (scores 2-4), and Grade 3 (scores 6-12). Higher expression grade was correlated with tumor thickness (P = 0.011), LN metastasis (P = 0.008), and higher EMPD stage (P = 0.023). Grade 1 EMPDs did not invade into the dermis and did not generate metastatic and/or recurrent lesions, whereas only Grade 2 or 3 EMPDs did so. AR expression in invasive components was significantly higher (P = 0.023) than in non-invasive components remaining within the epidermis. AR expression was further elevated in metastatic and/or recurrent lesions relative to locally invasive lesions (P = 0.014). These results clearly indicate that increased AR expression is associated with malignant progression of EMPD and that androgen blockade might be an effective therapy. Furthermore, AR expression assessed by immunohistochemistry may have potential for prediction of LN metastasis and local recurrence in EMPD.

Clinical severity scores as a guide for prediction of initial treatment responses in pemphigus and pemphigoid patients.

Pemphigus and pemphigoid are autoimmune blistering diseases that affect mucosa and skin. Several clinical scoring systems, including the pemphigus disease area index (PDAI) and the bullous pemphigoid disease area index (BPDAI), have been validated for managing disease activity and severity. Current guidelines recommend that treatment response be evaluated with clinical scores and that additional second-line therapies be considered if initial treatment is insufficient for disease control. However, there have been few studies analyzing correlations between PDAI/BPDAI transitions and initial treatment effects. To investigate whether PDAI/BPDAI transitions during the treatment initiation phase correlate with initial treatment responses and whether such information can be used as a guide for necessary additional treatment, we retrospectively analyzed 67 pemphigus patients and 47 pemphigoid patients who received initial treatment at Keio University between 2012 and 2018. The clinical symptoms were evaluated weekly with PDAI/BPDAI. The patients were divided into two groups: in group A, disease was controlled only with oral corticosteroids and immunosuppressants (initial treatment), whereas in group B additional therapies were required due to insufficient responses. In pemphigus, the PDAI ratio of day 7/day 0 was significantly reduced in group A compared to group B (0.548 vs 0.761, P < 0.01) after initial treatment had started. In pemphigoid, the ratios of day 7/day 0 of BPDAI (erosion/blister) and BPDAI (urticaria/erythema) significantly decreased in group A compared to group B (0.565 vs 0.901 and 0.350 vs 0.760, respectively, P < 0.05). Receiver operating characteristic analyses on PDAI, BPDAI (erosion/blister) and BPDAI (urticaria/erythema) revealed that the cut-off values in the ratios of day 7/day 0 were 0.762, 0.675, and 0.568, respectively. Our results suggest that PDAI/BPDAI transitions during the initial phase of the treatments may be useful to predict the outcome of the treatment provided and the necessity of additional therapies to achieve disease control.

Rituximab therapy for intractable pemphigus: A multicenter, open-label, single-arm, prospective study of 20 Japanese patients.

This was a multicenter clinical trial of rituximab, a chimeric monoclonal IgG antibody directed against CD20, for the treatment of refractory pemphigus vulgaris and pemphigus foliaceus. In total, 20 patients were treated with two doses of rituximab (1000 mg; 2 weeks apart) on days 0 and 14. The primary end point was the proportion of patients who achieved complete or partial remission on day 168 following the first rituximab dose. Of the 20 enrolled patients, 11 (55%) and four (20%) achieved complete and partial remission, respectively; therefore, remission was achieved in a total of 15 patients (75.0% [95% confidence interval, 50.9%-91.3%]). It was demonstrated that the remission rate was greater than the prespecified threshold (5%). In addition, a significant improvement in clinical score (Pemphigus Disease Area Index) and decrease in serum anti-desmoglein antibody level were observed over time. Four serious adverse events (heart failure, pneumonia, radial fracture, and osteonecrosis) were recorded in two patients, of which only pneumonia was considered causally related with rituximab. The level of peripheral blood CD19-positive B lymphocytes was decreased on day 28 after rituximab treatment and remained low throughout the study period until day 168. Our results confirm the efficacy and safety of rituximab therapy for refractory pemphigus in Japanese patients.

Cutaneous eyelid melanoma with lacrimal sac metastasis: the potential role of lacrimal fluid as a metastatic pathway.

Here we present a patient with cutaneous eyelid melanoma patient with lacrimal sac metastasis. Clinicopathological findings in this case support the theory that lacrimal fluid can be a metastatic pathway for tumour cells. Dermatologists should be aware of the possibility that cutaneous eyelid melanoma may involve the nasolacrimal system and should examine it during the perioperative period and in postoperative follow-up.

NY-ESO-1-specific redirected T cells with endogenous TCR knockdown mediate tumor response and cytokine release syndrome.

BACKGROUND: Because of the shortage of ideal cell surface antigens, the development of T-cell receptor (TCR)-engineered T cells (TCR-T) that target intracellular antigens such as NY-ESO-1 is a promising approach for treating patients with solid tumors. However, endogenous TCRs in vector-transduced T cells have been suggested to impair cell-surface expression of transduced TCR while generating mispaired TCRs that can become self-reactive. METHODS: We conducted a first-in-human phase I clinical trial with the TCR-transduced T-cell product (TBI-1301) in patients with NY-ESO-1-expressing solid tumors. In manufacturing TCR-T cells, we used a novel affinity-enhanced NY-ESO-1-specific TCR that was transduced by a retroviral vector that enables siRNA (small interfering RNA)-mediated silencing of endogenous TCR. The patients were divided into two cohorts. Cohort 1 was given a dose of 5×108 cells (whole cells including TCR-T cells) preconditioned with 1500 mg/m2 cyclophosphamide. Cohort 2 was given 5× 109 cells preconditioned with 1500 mg/m2 cyclophosphamide. RESULTS: In vitro study showed that both the CD8+ and CD4+ T fractions of TCR-T cells exhibited cytotoxic effects against NY-ESO-1-expressing tumor cells. Three patients and six patients were allocated to cohort 1 and cohort 2, respectively. Three of the six patients who received 5×109 cells showed tumor response, while three patients developed early-onset cytokine release syndrome (CRS). One of the patients developed a grade 3 lung injury associated with the infiltration of the TCR-T cells. No siRNA-related adverse events other than CRS were observed. Cytokines including interleukin 6 I and monocyte chemotactic protein-1/chemokine (C-C motif) ligand (CCL2)increased in the sera of patients with CRS. In vitro analysis showed these cytokines were not secreted from the T cells infused. A significant fraction of the manufactured T cells in patients with CRS was found to express either CD244, CD39, or both at high levels. CONCLUSIONS: The trial showed that endogenous TCR-silenced and affinity-enhanced NY-ESO-1 TCR-T cells were safely administered except for grade 3 lung injury. The TCR-T cell infusion exhibited significant tumor response and early-onset CRS in patients with tumors that express NY-ESO-1 at high levels. The differentiation properties of the manufactured T cells may be prognostic for TCR-T-related CRS. TRIAL REGISTRATION NUMBER: NCT02366546.

Severe graft-versus-host disease-like enterocolitis accompanied with cytomegalovirus-reactivation in drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms.

Drug-induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe drug adverse reaction with skin eruption and visceral organ involvement. The characteristic clinical features of DIHS/DRESS are reactivation of human herpesviruses (HHV) and the development of autoimmune diseases, but their pathogenesis and associations are not yet understood. Here, we report a 66-year-old man who presented with fever, generalized erythema, diffuse lymphadenopathy, and diarrhea after 3 weeks of treatment with zonisamide. Reactivation of HHV-6 and cytomegalovirus (CMV) was detected during the clinical course. The patient was diagnosed with DIHS/DRESS and treated with systemic prednisolone, i.v. immunoglobulin therapy, and ganciclovir. However, severe enterocolitis persisted for 6 months. A series of examinations revealed features of both CMV enterocolitis, as indicated by identification of a few CMV-positive cells on immunohistochemical analysis, and graft-versus-host disease (GVHD)-like enterocolitis indicated by orange-peel appearance on endoscopic examination and histopathological loss of goblet cells. Intractable enterocolitis continued and the patient finally died of pneumonia. An autoimmune predisposition in DIHS/DRESS patients in combination with CMV reactivation was considered to trigger the severe enterocolitis of this case that showed GVHD-like features of the gastrointestinal tract. GVHD-like organ damage is a pathological condition rarely observed in DIHS/DRESS but should be recognized as one of the most severe complications of the disease.

Concordance in judgment of clinical borders of basal cell carcinomas in Japanese patients: A preliminary study of JCOG2005 (J-BASE-MARGIN).

Basal cell carcinoma is the most common type of skin cancer, and surgical excision with clear margins is the standard of care. Surgical margins are determined based on risk factors (high or low risk) for recurrence according to the National Comprehensive Cancer Network and Japanese basal cell carcinoma guidelines. The clarity of the clinical tumor border (well-defined or poorly defined) is considered a risk factor, and significant discrepancies in the judgment of clinical tumor borders among dermato-oncologists may occur. Therefore, we analyzed the dermato-oncologists' concordance in judging the clinical tumor border of basal cell carcinoma. Forty-seven dermato-oncologists (experts: 37; young trainees: 10) participated in this study. The datasets of clinical and dermoscopic photographs of 79 Japanese cases of head and neck basal cell carcinoma were used to determine the concordance in the judgment of clinical tumor border. The probability of the border that was selected more often was used to calculate the rater agreement rate for each dataset. Correct judgment was defined as a more frequently selected border, and the concordance rate of clarity of clinical tumor border for each dermato-oncologist was calculated based on the definition of the correct judgment. A median concordance rate of 85% or higher for all dermato-oncologists was predefined as an acceptable rate for clinical use. Of the 79 datasets, rater agreement rates were 80-100%, 60-79%, and 51-59% for 55, 19, and five datasets, respectively. The median concordance rate for all dermato-oncologists was 86% (interquartile range: 82-89%). There was no significant difference in the concordance rate between the experts and the trainees (median, 87% vs. 85.5%; p = 0.58). The concordance rates of dermato-oncologists for all datasets were relatively high and acceptable for clinical use.

Management and outcomes of hydronephrosis in patients with metastatic extramammary Paget's disease: A retrospective analysis.

Hydronephrosis in extramammary Paget's disease (EMPD) with distant metastasis (metastatic EMPD) has been observed in medical practice; however, its prognosis remains unclear. Retrospective analyses were performed to assess the management and outcomes of hydronephrosis in metastatic EMPD. During a follow-up of 44 patients with metastatic EMPD, 13 (30%) developed hydronephrosis. Ten (77%) of the 13 patients with hydronephrosis had impaired renal function (estimated glomerular filtration rate: <60 ml/min/1.73 m2 ), and ureteral stents were placed in every patient with impaired renal function. The stent was placed successfully in all 10 patients, and their renal function recovered within a median period of 7 days. Importantly, each of these patients continued chemotherapy, and none of them experienced stent failure. The median overall survival time (OS) in patients with metastatic EMPD and hydronephrosis (n = 13) was 7.8 months. Treatment for hydronephrosis was not a significant factor for OS, and median OS in patients who underwent ureteral stent replacement (n = 10) was 14.7 months. Collectively, our results indicate that hydronephrosis is relatively common, and ureteral stent placement should be considered in cases of metastatic EMPD with hydronephrosis to maintain renal function and continue chemotherapy toward a better prognosis.

Safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma: Real-world experience from post-marketing surveillance.

To establish real-world evidence about the safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma, we conducted a nationwide cohort study using data from post-marketing surveillance for bexarotene treatment. In total, 294 patients with cutaneous T-cell lymphoma were identified between June 2016 and June 2018. Of these, 267 patients were included as the safety analysis set. Of the 267 patients, 175 were included in the efficacy analysis set. Of these, 139 patients had mycosis fungoides, including 46 with early stage disease and 93 with advanced stage disease. Among the 139 patients with mycosis fungoides, the objective response rate was 46.8%. A significant difference in objective response rate was detected between patients who started with bexarotene at 300 mg/m2 (61.6%) and patients who started with bexarotene at less than 300 mg/m2 (22.6%, p < 0.001). Of the 139 patients with mycosis fungoides, 92 were treated with a combination of bexarotene plus photo(chemo)therapy. A significant difference in objective response rate was seen between bexarotene with a combination of photo(chemo)therapy (57.6%) and bexarotene without a combination of photo(chemo)therapy (25.5%, p < 0.001). Starting bexarotene at 300 mg/m2 and combination with photo(chemo)therapy were detected as independent factors influencing response. Common treatment-related adverse events included hypothyroidism (85.8%), hypertriglyceridemia (68.5%), hypercholesterolemia (43.8%), and neutropenia (21.3%). Hypertriglyceridemia, hypercholesterolemia, and neutropenia occurred more frequently in patients who started with bexarotene at 300 mg/m2 than patients who started with bexarotene at less than 300 mg/m2 (hypertriglyceridemia, 76.4% vs. 57.0%, p = 0.001; hypercholesterolemia, 49.0% vs. 36.4%, p = 0.045; neutropenia, 28.0% vs. 12.1%, p = 0.002; respectively). The present study indicates that starting bexarotene at 300 mg/m2 and combination of photo(chemo)therapy offer a promising efficacy for the treatment of patients with mycosis fungoides. Efficacy of low-dose bexarotene plus photo(chemo)therapy should be evaluated in future.