Anti-PD1 checkpoint inhibitor therapy in acral melanoma: a multicenter study of 193 Japanese patients

BACKGROUND

Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM.

PATIENTS AND METHODS

We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies.

RESULTS

In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03).

CONCLUSIONS

Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.

Squamous cell carcinoma arising from lupus vulgaris with a >60-year history

We report the case of a 71-year-old Japanese man with squamous cell carcinoma arising from lupus vulgaris on the face, >60 years after the appearance of the lupus vulgaris. The red plaque on the patient's face had been diagnosed as a hemangioma or rosacea at several hospitals, although he had had lung tuberculosis at the age of 4 and his father died from lung tuberculosis at 38 years of age. Although lupus vulgaris was the most frequent clinical form of true skin tuberculosis until the 1960s, it has become rare since then. Malignant tumors are known to occur in individuals with lupus vulgaris, with a reported rate of 0.5-10.5%. In light of Japan's "graying society," tuberculosis is still an important disorder, and clinicians must remain aware of cutaneous tuberculosis.

Fish collagen is an important panallergen in the Japanese population

Collagen was identified as a fish allergen in early 2000s. Although its allergenic potential has been suggested to be low, risks associated with collagen as a fish allergen have not been evaluated to a greater extent. In this study, we aimed to clarify the importance of collagen as a fish allergen. Our results showed that 50% of Japanese patients with fish allergy had immunoglobulin E (IgE) against mackerel collagen, whereas 44% had IgE against mackerel parvalbumin. IgE inhibition assay revealed high cross-reactivity of mackerel collagen to 22 fish species (inhibition rates: 87-98%). Furthermore, a recently developed allergy test demonstrated that collagen triggered IgE cross-linking on mast cells. These data indicate that fish collagen is an important and very common panallergen in fish consumed in Japan. The high rate of individuals' collagen allergy may be attributable to the traditional Japanese custom of raw fish consumption.

Phase II study of the immune-checkpoint inhibitor ipilimumab plus dacarbazine in Japanese patients with previously untreated, unresectable or metastatic melanoma

PURPOSE

Ipilimumab (IPI), a monoclonal antibody against immune-checkpoint receptor cytotoxic T lymphocyte antigen-4, is designed to enhance antitumor T cell function. IPI 10 mg/kg plus dacarbazine (DTIC) significantly improved overall survival in a phase 3 study involving predominantly Caucasian patients, with an adverse event (AE) profile similar to that of IPI monotherapy. We conducted a single-arm, phase 2 study to evaluate the safety and efficacy of IPI plus DTIC in Japanese patients.

METHODS

Previously untreated patients with unresectable stage III or IV melanoma received IPI 10 mg/kg plus DTIC 850 mg/m(2) every 3 weeks for four doses (q3w × 4), followed by DTIC q3w × 4 and then IPI every 12 weeks until disease progression or intolerable toxicity.

RESULTS

All 15 treated patients reported drug-related AEs, the most common of which were increases in alanine aminotransferase (n = 12, 80 %) and aspartate aminotransferase (n = 11, 73 %). Treatment-related serious AEs were reported in 11 (73 %) patients. Nine patients (60 %) discontinued treatment due to drug-related toxicities. Immune-related AEs (irAEs) were reported in 14 patients (93 %). The most frequent irAEs were liver (n = 12, 80 %) and skin (n = 10, 67 %) toxicities. Five deaths were reported; all were caused by progressive disease. Efficacy evaluation showed one complete response, one partial response and four patients with stable disease. Best overall response rate was 13 % (2/15), and the disease control rate was 40 % (6/15). The study was terminated early due to frequent, high-grade liver toxicities.

CONCLUSIONS

IPI 10 mg/kg plus DTIC 850 mg/m(2) was not considered tolerable in the Japanese patient population. ClinicalTrials.gov identifier: NCT01681212.

Clinical course of drug-induced hypersensitivity syndrome treated without systemic corticosteroids

BACKGROUND/AIM

Drug-induced hypersensitivity syndrome (DIHS) is a severe reaction to drugs which characteristically occurs after a long latency period. In addition, human herpes virus 6 (HHV-6) reactivation is a characteristic finding in DIHS, which has been known to be related to disease severity. Because DIHS has generally been treated by systemic corticosteroids, the natural clinical course is not clear.

METHODS

Data for patients with both DIHS and HHV-6 reactivation were retrospectively collected from four hospitals.

RESULTS

Data were collected on 12 patients ranging in age from 21 to 76 years (median, 65.5). All cases had been suspected of DIHS at their initial visit, and the elevation of serum anti-HHV-6 antibody had been confirmed (4-256 times: median; 32). The culprit drugs were carbamazepine (6), salazosulfapyridine (4), mexiletine (1) and zonisamide (1). The period of latency from the first administration of the drug ranged from 15 to 50 days (median, 30). All patients were treated conservatively for DIHS without systemic corticosteroids. The peaks of the patients' symptoms and laboratory findings were as follows (days from the onset of skin lesions): fever, 4-16 (median, 10.5); liver abnormality, 3-22 (median, 7.5); leukocytosis, 7-20 (median, 9). All patients recovered without pneumonia, myocarditis, nephritis or other systemic disease, from 7 to 37 days (median, 18) after withdrawal of the drug and from 11 to 44 days (median, 21) after the onset of skin lesions.

CONCLUSION

It might be unnecessary to give systemic corticosteroids immediately to all patients suspected of having DIHS.

Mutation analysis of BRAF and KIT in circulating melanoma cells at the single cell level

Background:

The availability of molecular-targeted therapies for the treatment of melanoma has emphasised the need to identify mutations in target genes such as BRAF and KIT. Circulating tumour cells (CTC) are present in the peripheral blood of a significant proportion of cancer patients.

Methods:

High molecular weight melanoma-associated antigen (HMW-MAA) was used to isolate melanoma cells from peripheral blood as it is selectively expressed at high levels on melanomas. The HMW-MAA-positive cells were isolated using immunomagnetic beads. After removing CD45⁺ cells, CTC were identified by staining with MART-1- and gp100-specific antibodies (HMW-MAA⁺, CD45⁻, MART-1/gp100⁺). Single, isolated CTC were then subjected to BRAF and KIT mutational analysis.

Results:

CTC (HMW-MAA⁺, CD45⁻, MART-1/gp100⁺) were isolated from the blood of 11 patients and BRAF and KIT were sequenced in nine and four patients, respectively. The BRAF sequences identified in the CTC were inconsistent with those identified in autologous melanoma tumours in three patients and the KIT sequences were inconsistent in three patients. In addition, polyclonal BRAF mutations were identified in one patient and concomitant mutations in BRAF and KIT were identified in another patient.

Conclusion:

Melanoma cells show clonal heterogeneity. Therefore, CTC genotyping may be crucial for successful molecular-targeted therapy.

Estrogen-Receptor-Alpha-Positive Extramammary Paget’s Disease Treated with Hormonal Therapy

The patient was an 80-year-old man with scrotal and penile extramammary Paget's disease and prostate cancer. Both diseases were in advanced stages. Tumor cells of extramammary Paget's disease strongly expressed estrogen receptor alpha. The patient was concurrently treated with two kinds of hormonal therapy: the anti-estrogen tamoxifen (20 mg/day orally) for extramammary Paget's disease and the anti-androgen bicalutamide (80 mg/day orally) for prostate cancer. The toxicity of the therapy was mild. All of the metastatic lesions remained stable for 2 months after initiation of dual hormonal therapy. During a follow-up period of 22 months, performance status was well maintained for 17 months. Hormonal therapy may be an alternative for selected cases of advanced extramammary Paget's disease.

Evaluation of 5-S-cysteinyldopa as a marker of melanoma progression: 10 years' experience

5-S-Cysteinyldopa (5-S-CD) has been used as a biochemical marker of melanoma progression. In this study, we measured serum levels of 5-S-CD in 2648 samples taken from 218 patients in order to evaluate the usefulness of this parameter in following melanoma progression and prognosis. 5-S-CD levels were significantly elevated above the upper limit of the normal range (10 nmol/l) in stage IV melanoma patients. The sensitivity of elevated serum 5-S-CD levels in detecting distant metastasis was 73%, while the specificity was 98% and the positive predictive value 94%. The sensitivity was improved to 77% when cases of amelanotic melanoma were excluded. Patients without metastases had elevated 5-S-CD values in 5% of the 1480 serum samples. Changes in serum 5-S-CD levels were followed during disease progression until the end stage in 49 patients. In 33% of the patients, elevation of serum 5-S-CD levels preceded clinical detection of visceral metastases, and in 37% elevation of 5-S-CD levels occurred at the same time as visceral metastasis. Patients with elevated 5-S-CD levels before or after surgical treatment had significantly shorter survival times than those with normal levels. These results show that the level of 5-S-CD in the serum is a sensitive and specific marker in predicting distant metastases. Elevated serum levels of 5-S-CD, before or after surgical treatment, is associated with a poor prognosis.

Solid facial edema in a patient with rosacea

We report a 53-year old man with symmetrical nonpitting edema, conjunctivitis, and acneiform eruptions on the face. Histopathological examination showed perifollicular lymphohistiocytic infiltration and telangiectasias in the upper dermis. Loosely aggregated non-caseating granulomas were scattered through the dermis; some of them were seen in the perifollicular regions. The patient was treated with fleroxacin (100 mg/day, orally) for two weeks with a marked reduction of both solid facial edema and periorbital edema.

Immunohistochemical detection of CDK4 and p16INK4 proteins in cutaneous malignant melanoma

p16INK4 gene, which encodes a specific inhibitor of cyclin-dependent kinase 4 (CDK4), has been recently reported as an important tumour suppressor gene. It is mapped to chromosome 9p21, which is frequently deleted or mutated in many tumour cell lines including malignant melanoma. Since the CDK4/cyclin D complex propels a cell to go through the G1 check point of the cell cycle, a critical phase of cell division, alteration of the p16INK4 gene could lead a cell to uncontrolled proliferation and malignant transformation. To clarify any role for p16INK4 and CDK4 proteins in the development of human malignant melanoma, we have examined, immunohistochemically, the expression of these two proteins in melanocytic neoplasms including 19 primary lesions of non-familial melanoma. Intense nuclear and/or cytoplasmic expression of the CDK4 protein was observed in 11 of 19 cases (58%) of melanoma. In contrast, virtually no nuclear or cytoplasmic staining for CDK4 protein was detected in 28 benign melanocytic naevi, including six Spitz naevi. Expression of p16INK4 protein was observed in three of 19 melanomas (16%) and in 17 of 28 benign naevi (61%). Inverse expression of CDK4 and p16INK4, at individual cell level, was detected in one case of melanoma. The present study suggests that CDK4 overexpression is characteristic for malignant melanoma, and probably reflects its autonomous accelerated cell proliferation. The expression rate of p16INK4 protein in malignant melanoma was lower than that in benign naevi, although the significance of p16INK4 deletion in melanoma development has not been definitely confirmed.

Expression of alpha subunit of guanine nucleotide-binding protein Go in Merkel cell carcinoma

The alpha subunit of guanine nucleotide-binding protein Go (Go alpha), which was initially isolated from bovine brain, interacts with muscarinic cholinergic receptors and regulates neuronal calcium channels. Go alpha is known to be localized in neural tissues, some endocrine cells, and neuroendocrine tumors. We have immunohistochemically investigated the expression of Go alpha in 4 cases of Merkel cell carcinoma using the method of microwave treatment. In all cases of Merkel cell carcinoma, Go alpha was consistently detected on the plasma membrane and cytoplasm of the tumor cells. Nerve fibers in the skin were also positive for Go alpha, but other epidermal or dermal components such as keratinocytes, melanocytes, fibroblasts, or lymphoid cells were negative. Tumor cells of squamous cell carcinoma, cutaneous lymphoma, sweat gland carcinoma, and malignant melanoma were negative for Go alpha. The present study indicates that Go alpha may be a useful immunohistochemical marker of Merkel cell carcinoma.

Primary cutaneous plasmacytosis: report of three cases and review of the literature

BACKGROUND

Cutaneous plasmacytosis is a rare disease characterized by peculiar multiple eruptions and hypergammaglobulinemia. More than 40 cases have been reported, mainly in Japan, although information concerning the disorder was limited to individual case reports.

OBJECTIVE AND METHODS

To clarify the clinicopathological and laboratory features, we reviewed 41 cases.

RESULTS

All patients were Japanese and the male-to-female ratio was 1:0.6. The onset ages ranged from 20 to 62 years, with a mean and median of 37 and 37 years. A superficial lymphadenopathy was detected in 58% (22/38), and polyclonal hypergammaglobulinemia was found in 93% (38/41). No cases were associated with any apparent underlying diseases. The course was chronic without spontaneous remission. Four patients died, 3 of whom succumbed to leukemia, respiratory failure or renal failure, respectively.

CONCLUSION

The results suggest that the condition appears to be a variant of reactive plasmacytic disorders of unknown origin.

Detection of Epstein-Barr virus DNA in a Japanese case of lymphoepithelioma-like thymic carcinoma

Epstein-Barr virus DNA was detected in a case of lymphoepithelioma-like thymic carcinoma. A homogeneous terminal structure of the viral DNA was demonstrated in this case, indicating the presence of the viral genome in clonally expanded tumor cells. Since all of 26 other thymic epithelial tumors (eight non-invasive, 13 invasive thymomas and four non-lymphoepithelioma-like thymic carcinomas) in Japanese were negative by polymerase chain reaction, it is suggested that lymphoepithelioma-like thymic carcinoma may represent a unique pathological entity distinct from Epstein-Barr virus-negative thymic epithelial tumors, which are in the majority in Japan.

Detection of Epstein-Barr virus DNA in formalin-fixed paraffin-embedded tissue of nasopharyngeal carcinoma using polymerase chain reaction and in situ hybridization

The polymerase chain reaction method for amplification of DNA in formalin-fixed, paraffin-embedded tissue sections was used to detect Epstein-Barr virus DNA in nasopharyngeal carcinomas from Japanese patients. Thirty-one cases of nasopharyngeal carcinoma and 8 cases of lymph node metastasis of nasopharyngeal carcinoma were studied. Detection rates of Epstein-Barr virus in various types of nasopharyngeal carcinoma according to the World Health Organization classification were as follows: 10 of 10 undifferentiated carcinomas, 8 of 13 nonkeratinizing carcinomas, and 5 of 7 keratinizing carcinomas. Eight lymph node metastases, for which the primary was positive for Epstein-Barr virus, also contained Epstein-Barr virus DNA. By in situ hybridization using a biotinylated Epstein-Barr virus probe, it was clearly demonstrated that Epstein-Barr virus DNA was localized in the nuclei of the neoplastic cells. The clinical features of nasopharyngeal carcinoma with or without Epstein-Barr virus were not different. These results demonstrate that nasopharyngeal carcinoma in Japanese patients is closely associated with Epstein-Barr virus infection, similar to nasopharyngeal carcinoma of other endemic and nonendemic areas.

Detection of human papillomavirus DNA in laryngeal squamous cell carcinomas by polymerase chain reaction

The presence of human papillomavirus genomes-16 and -6b in metastatic cervical lymph nodes was examined in 34 cases of laryngeal carcinomas by means of polymerase chain reaction, which had been fixed in formalin and embedded in paraffin. Human papillomavirus DNAs extracted from paraffin-embedded tumor tissues were used for polymerase chain reaction with amplification of the E6 region of human papillomavirus genome-16 and the E1 region of human papillomavirus genome-6b. Human papillomavirus genome-16 sequences were positively amplified in six (17.6%) metastatic tumors; -6b sequence was positively amplified in one (2.9%) metastatic tumor. Laryngeal carcinomas of glottic origin showed high human papillomavirus genome-16 DNA-positive rates (4 of 9 cases, 44.4%) compared to those of other sites. These results suggest that human papillomavirus genome-16 infection might be closely associated with the development of some laryngeal squamous cell carcinomas of glottic origin similar to uterine cervical carcino-genesis.

Detection of Epstein-Barr virus DNA in Reed-Sternberg cells of Hodgkin's disease using the polymerase chain reaction and in situ hybridization

Thirty-one cases of Hodgkin's disease were examined for the occurrence of Epstein-Barr virus (EBV) genome by using the polymerase chain reaction (PCR) of DNA in formalin-fixed paraffin-embedded tissues and in situ hybridization technique. The cases were subdivided into 17 cases of nodular sclerosis (NS), nine cases of mixed cellularity (MC), four cases of lymphocyte predominance (LP), and one case of lymphocyte depletion (LD). EBV DNA was detected in eight cases including four cases of NS, three cases of MC and one case of LP. The sensitivity of PCR was higher than that of Southern blot hybridization of DNA from fresh frozen tissue, because Southern blot hybridization using the BamHI-W fragment of EBV detected virus DNA only in two of three cases which were positive by PCR. The results of in situ hybridization studies confirmed that EBV genome was localized within the nuclei of Reed-Sternberg (RS) cells and their mononuclear variants. Furthermore, double-labeling studies combining in situ hybridization and immunocytochemistry using CD30 (BerH2) and CD15 (LeuM1) as markers of RS cells, as well as pan B-marker (L26) and pan T-marker, CD45RO (UCHL1), were performed to demonstrate the phenotype of EBV DNA-positive cells, confirming that EBV DNA was present in RS cells but not in lymphocytes. The results of this study indicate a significant association between EBV and some cases of Hodgkin's disease.

Bowen's disease with invasive carcinoma showing sweat gland differentiation

A 75-year-old Japanese woman presented an erythematous macular lesion on the flexor aspect of her left wrist. A reddish nodule, 4 mm in diameter, was observed at the medial portion of the macule. The macular lesion was histologically confirmed to be a typical Bowen's disease. The nodular lesion was composed of intradermal solid nests of bowenoid neoplastic cells, and in some areas of the dermal component, prominent gland-like structures were observed. Immunohistochemically, most neoplastic cells of the intradermal solid nests were positive with S-100 protein, and the cells lining the gland-like structures along with amorphous material within the lumens were positive with carcinoembryonic antigen. Judging from these findings, this case was diagnosed as Bowen's disease with invasive carcinoma, whose dermal component showed sweat gland differentiation not only morphologically but also immunohistochemically.

Heterophile Hanganutziu-Deicher antigen in ganglioside fractions of human melanoma tissues

Gangliosides were purified from melanoma tissue extracts obtained from 5 patients. GM3 and GD3 were identified as the major components in ganglioside fractions of the melanoma tissues. Following thin-layer chromatography, enzyme immunostaining with Hanganutziu-Deicher (H-D) antigen-specific chicken antisera demonstrated the presence of NeuGc-neolactotetraosylceramide (H-D5) and NeuGc-lacto-N-norhexa-osylceramide (H-D7) in all 5 melanoma extracts.