Transoral robotic-assisted free flap reconstruction after radiation therapy in hypopharyngeal carcinoma: report of two cases.

The objective was to assess the feasibility and safety of transoral robotic surgery (TORS)-assisted free flap reconstruction for hypopharyngeal carcinoma after radiation therapy. The study evaluated the feasibility, surgical margins, the need for a tracheotomy, a nasogastric tube as well as surgery-related complications. Two patients underwent TORS-assisted free flap reconstruction after radiation therapy. The resection margins were free of tumor in both patients. A tracheotomy was performed in one patient who had been decannulated on the sixth postoperative day. One patient resumed satisfactory oral feeding in the fourth postoperative month and the second patient on postoperative day 7. No intraoperative complication and one postoperative complication (neck hematoma) were reported. After a follow-up period of 24 and 30 months, no local recurrence was observed. TORS is feasible for hypopharyngeal resection and assisted free flap reconstruction after radiation therapy. It represents a further step in the development of minimally invasive surgery for the treatment of head and neck cancers with laryngeal preservation.

Immunologically active phenotype by gene expression profiling is associated with clinical benefit from PD-1/PD-L1 inhibitors in real-world head and neck and lung cancer patients.

INTRODUCTION: Identification of tumours harbouring an overall active immune phenotype may help for selecting patients with advanced head and neck squamous cell carcinomas (HNSCC) and non-small cell lung cancer (NSCLC) who may benefit from immunotherapies. Our objective was to develop a reliable and stable scoring system to identify those immunologically active tumours. METHODS: Using gene expression profiles of 421 HNSCC, we developed a score to identify immunologically active tumours. Validation of the 'HOT' score was done in 40 HNSCC and 992 NSCLC. Stability of the 'HOT' score was tested in paired HNSCC samples from diagnostic biopsies versus surgically resected specimens, untreated versus recurrent samples, and pre-versus post-cetuximab samples in a total of 76 patients. The association between the 'HOT' score with overall survival (OS) and progression-free survival (PFS) was tested in 184 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors. RESULTS: A 27-gene expression based 'HOT' score was correlated with: (i) PD-L1 and IDO1 expression, (ii) TCD8 infiltrate and (iii) activation of the IFN-γ pathway. The HOT score concordance when comparing diagnostic biopsies and surgically resected specimens was higher than in untreated samples versus recurrent or pre-versus post-cetuximab samples. In 102 and 82 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors, the HOT score was associated with an improved OS and PFS in multivariate analysis. CONCLUSION: The 'HOT' score is a simple and robust approach to identify real-world patients with HNSCC and NSCLC immunologically active tumours who may benefit from PD-1/PD-L1 inhibitors.

Datasets for gene expression profiles of head and neck squamous cell carcinoma and lung cancer treated or not by PD1/PD-L1 inhibitors.

Identification of tumors harboring an overall active immune phenotype may help for selecting patients with advanced head and neck squamous cell carcinomas (HNSCC) and non-small cell lung cancer (NSCLC) who may benefit from immunotherapies. In this context, we generated targeted gene expression profiles in three and two independent cohorts of patients with HNSCC or NSCLC respectively, treated or not by PD-1/PD-L1 inhibitors. Notably, we generated two datasets including 102 and 82 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors. Clinical information, including detailed survival raw data, is available for each patient, allowing to test association between gene expression data and patient survival (overall and progression-free survival). Moreover, we also generated gene expression datasets of 27 paired HNSCC samples from diagnostic biopsies and versus surgically resected specimens as well as 33 paired HNSCC samples at initial diagnosis (untreated) and at recurrence. Those datasets may allow to test the stability of a given biomarker across paired samples.

Metallothionein expression in mobile tongue squamous cell carcinoma: associations with clinicopathological parameters and patient survival.

AIMS: Metallothionein (MT) has been implicated in several aspects of cancer pathobiology, such as differentiation, proliferation, apoptosis and invasion. The aim of the present study was to evaluate the clinical significance of MT expression in mobile tongue squamous cell carcinoma (SCC). METHODS AND RESULTS: MT protein expression was assessed immunohistochemically on 49 mobile tongue SCC specimens, and was analysed in relation to clinicopathological characteristics, and overall and disease-free patient survival. All of the examined mobile tongue SCC cases showed MT positivity in tumour cells; however, neither MT overexpression nor staining intensity was significantly associated with clinicopathological parameters. MT cellular distribution was significantly associated with histopathological grade of differentiation and depth of invasion (P = 0.0188 and P = 0.0484, respectively). MT staining intensity was identified as a significant predictor of overall patient survival at both univariate (P = 0.0377) and multivariate (P = 0.0472) levels. Twenty-seven (55.10%) of the examined SCC cases showed MT positivity in squamous tongue epithelium adjacent to the tumour, the MT positivity being correlated with depth of invasion (P = 0.0281), vascular invasion (P = 0.0194), and the existence of lymph node metastases (P = 0.0194). CONCLUSIONS: MT may be implicated in the development and progression of mobile tongue SCC and could be considered as a useful clinical marker for patient management and prognosis.

Expression of DNA repair proteins, MSH2, MLH1 and MGMT in mobile tongue squamous cell carcinoma: associations with clinicopathological parameters and patients' survival.

BACKGROUND: DNA repair is a major defense mechanism, which contributes to the maintenance of genetic sequence, minimizing cell death, mutation rates, replication errors, DNA damage persistence and genomic instability. Alterations of proteins participating in DNA repair mechanisms have been associated with several aspects of cancer biology. The present study aimed to evaluate the clinical significance of DNA repair proteins, MSH2, MLH1 and MGMT in mobile tongue squamous cell carcinoma (SCC). METHODS: MSH2, MLH1 and MGMT protein expression was assessed immunohistochemically on 49 mobile tongue SCC tissue samples and was analyzed in relation with clinicopathological characteristics, overall and disease-free patients' survival. RESULTS: MSH2 expression was significantly associated with depth of invasion (P=0.0335), tumor shape (P=0.0396) and muscular invasion (P=0.0098). MLH1 expression was significantly associated with lymph node metastases (P=0.0484) and borderline with perineural invasion (P=0.0699). MGMT expression was significantly associated with depth of invasion (P=0.0472), tumor shape (P=0.0187), perineural invasion (P=0.0115) and lymph node metastases (P=0.0032) and borderline with vascular invasion (P=0.0755). MSH2 expression was significantly associated with disease-free patients' survival in univariate analysis (P=0.0441), being also identified as an independent prognostic factor in multivariate analysis (P=0.0451). CONCLUSIONS: The present study supported evidence for possible implication of MSH2, MLH1 and MGMT proteins in the formation and progression of mobile tongue SCC.

Histone deacetylase-1 and -2 expression in mobile tongue squamous cell carcinoma: associations with clinicopathological parameters and patients survival.

BACKGROUND: Histone deacetylases (HDACs) have been associated with tumor development and progression in several types of human malignancy and HDAC inhibitors are currently being explored as anti-cancer agents in clinical trials. The aim of the present study was to evaluate the clinical significance of HDAC-1 and -2 protein expression in mobile tongue squamous cell carcinoma (SCC). METHODS: HDAC-1 and -2 protein expression was assessed immunohistochemically on 49 mobile tongue SCC tissue samples and was analyzed in relation with clinicopathological characteristics, overall and disease-free patients' survival. RESULTS: HDAC-1 overexpression was significantly associated with younger patients' age (P = 0.0381) and male gender (P = 0.0345), poor histopathological grade of differentiation (P = 0.0236) and the presence of lymph node metastases (P = 0.0104). Intense HDAC-1 staining intensity was significantly associated with male gender (P = 0.0127), increased stromal infiltration reaction (P = 0.0125) and well-defined shape of tumor invasion (P = 0.0396). HDAC-2 overexpression did not show significant correlations with any clinicopathological parameters, whereas intense HDAC-2 staining intensity was significantly associated with the presence of muscular invasion (P = 0.0466) and advanced depth of invasion (P = 0.0251). Mobile tongue SCC patients with HDAC-1 overexpression presented shorter overall and disease-free survival compared to those with no evidence of HDAC-1 overexpression (log-rank test, P = 0.0651 and 0.0247, respectively). CONCLUSIONS: The present study supported evidence that HDACs may participate in the formation and progression of mobile tongue SCC, reinforcing their possible use as biomarkers as also the therapeutic utility of HDAC inhibitors in mobile tongue SCC chemoprevention and treatment.

Giant basal cell carcinoma with regional lymph node and distant lung metastasis.

The prevalence of metastatic basal cell carcinoma (MBCC) varies between 0.0028% and 0.55% of all cases. In total, more than 300 MBCC have been reported in the literature. We report the case of a 72 year old lady, who presented in September 2009 with a 10-year history of a progressively growing, giant, facial basal cell carcinoma (BCC). Clinical and imaging evaluations identified large local invasion with bone and meningeal involvement. Treatment consisted of an extensive surgery including left eye exenteration and meningeal resection followed by radiotherapy. A solitary lung metastasis was identified five months after the primary tumor resection. As the lesion remained solitary but had increased in size five months later, the patient finally accepted a surgical resection. A right upper-lobe pneumonectomy was performed and pathologic examination confirmed the metastasis as a MBCC.

RCAS1 expression in mobile tongue squamous cell carcinoma: an immunohistochemical study.

BACKGROUND: The receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a human tumor-associated antigen that has been considered to play a crucial role in tumor progression by enabling cancer cells to evade immune surveillance. The present study aimed to evaluate the clinical significance of RCAS1 expression in mobile tongue squamous cell carcinoma (SCC). MATERIAL/METHODS: RCAS1 protein expression was assessed immunohistochemically on 49 mobile tongue SCC tissue samples obtained from an equal number of patients and was statistically analyzed with clinicopathological characteristics and overall and disease-free patients' survival. RESULTS: Enhanced RCAS1 expression was significantly associated with reduced depth of invasion (p=0.0069), low mitotic index (p=0.0251) and no evidence of muscular invasion (p=0.0098). A borderline association between RCAS1 expression and stromal inflammatory reaction was also noted (p=0.0660). RCAS1 expression was not associated with overall and disease-free survival. CONCLUSIONS: Our data support evidence for possible implication of RCAS1 at the early stage of tumor progression in mobile tongue SCC, whereas the survival prediction using RCAS1 expression as a clinical marker seems uncertain for this type of malignancy.

Sentinel lymph node biopsy or nodal observation in melanoma: a prospective study of patient choices.

BACKGROUND: There is no consensus regarding the therapeutic utility of sentinel lymph node biopsy (SLNB) versus that of nodal observation (NO) in melanoma. OBJECTIVE: To prospectively evaluate a standardized counseling procedure and its effect on patient choices to undergo SLNB or NO. METHODS: In four centers, patients with melanoma eligible for SLNB or NO received a complete counseling procedure that included verbal information from dermatologists and surgeons, a detailed information sheet, and a written consent form. Data collected included patient and tumor characteristics, counseling conditions, and specialties of informing doctors. Factors influencing patients' choices were studied using multivariate analysis. RESULTS: Of 343 consecutive patients, 309 were offered SLNB and NO and received complete verbal and written information from a dermatologist alone (62%) or in association with a surgeon (38%). Approximately half took advice from trusted persons, and half asked for additional time before making a decision; 268 (86.7%) ultimately decided to undergo SLNB. Multivariate analysis showed that older patients, those with a head and neck melanoma, and those informed without a surgeon present were more likely to prefer NO. CONCLUSIONS: This counseling procedure was easily implemented in clinical practice. Patients favored SLNB but were able to understand uncertainties and express preferences.

Prognostic significance of tumor shape and stromal chronic inflammatory infiltration in squamous cell carcinomas of the oral tongue.

BACKGROUND: Squamous cell carcinoma (SCC) of the oral tongue is well known to be an aggressive disease with early metastatic spread in early stage tumors. It is also established that locoregional recurrences are the main causes of treatment failure. Thus, the identification of histopathological factors possessing a predictive value remains important for the management of the disease. The aim of the present study was to define histopathological parameters of the tumor and to compare with the follow-up and status in primary SCCs of the mobile tongue. METHODS: Histopathological parameters such as mitotic index, the presence of vascular emboli or perineural invasion, the thickness of the tumor, the histological grade, the tumor shape as well as chronic stromal inflammatory infiltration were assessed in 52 patients with SCC of the mobile tongue and compared with the follow-up and status in patients treated initially by surgery. RESULTS: Tumor shape was significantly associated with the presence of perineural invasion. Well-defined shaped tumors displayed almost half the incidence of perineural invasion when compared with ill-defined shaped tumors. In addition, the high density of the chronic inflammatory infiltration of the stroma exhibited significant correlation with the survival of the patients. Finally, the intense chronic inflammatory infiltration of the stroma was associated with well-defined shaped tumors. CONCLUSION: Tumor shape and stromal chronic inflammatory infiltration should be considered in the planning of the management of patients with SCC of the mobile tongue.

Women and squamous cell carcinomas of the oral cavity and oropharynx: is there something new?

PURPOSE: Incidence of squamous cell carcinoma (SCC) of the oral cavity and oropharynx is increasing in French female patients. The objective of this study was to study the clinical and demographic characteristics and the prognosis of this female population. Secondary outcomes were to determine if a subgroup of patient had a different prognosis. MATERIALS AND METHODS: A prospective study from 1989 to 2002 of all female patients presenting SCC of the upper aerodogestive tract was conducted. Data for 171 women were extracted. Clinical and histological features were analyzed using chi(2) and log-rank tests along with the Kaplan Meier method and multivariate analysis using the Cox regression procedure. RESULTS: Mean patient age was 62 years. Of the study population, 48.5% used tobacco and 34.5% used alcohol. The relative risk of death for overall and cancer-specific survival increased for patients below the age of 45 or over the age of 70 (95% Cl; 0.3-1.05; P = .0085). Tobacco consumption decreased cancer-specific and overall survival (P = .0008 and .0001, respectively). The other prognostic factors we found were tumor and nodal status, previous or simultaneous cancer, oral cavity primary site. CONCLUSIONS: Prognosis of oropharyngeal and oral squamous cell carcinomas is less favorable in females who smoke as well as in younger and older women. With these patients, the oversight must be closer. Smoking, however, should be stopped.

Two types of squamous cell carcinoma of the palatine tonsil characterized by distinct etiology, molecular features and outcome.

To determine whether human papillomaviruses (HPV) positive tonsillar squamous cell carcinoma (SCC) represent a specific entity, we studied the prevalence of HPV association and of tobacco/alcohol exposure in a series of 52 cases of tonsillar SCC cases. p53, p16, and pRb levels, deregulated by viral oncoproteins were assessed. Forty patients reported tobacco/alcohol exposure, 10 reported no exposure. HPV DNA was found in 32/52 (62%) cases, (HPV16 genotype in 27). All patients with no history of tobacco-alcohol exposure presented HPV positive tumor (p=0.0008). A strong correlation was observed between positive HPV status, decrease in pRB and increase in p16 expression level. 5 year overall survival rate was higher in HPV16 positive patients than in HPV negative (71% versus 36%; p=0.023). HPV status remained a significant prognostic factor in multivariate analysis. Tonsillar SCC can thus be divided in HPV positive and negative subgroups with different oncogenesis and response to treatment.

[First outpatient satisfaction questionnaire with day-surgery in a French comprehensive cancer center]. / Première enquête de satisfaction dans une unité de chirurgie ambulatoire dédiée à la cancérologie.

INTRODUCTION: To assess the patient's satisfaction in a day-surgery unit in oncology for a surgical diagnosis or therapeutic act. METHODS: Between October 2013 and February 2014, we conducted a satisfaction survey from the validated questionnaire COPS-D. This questionnaire analyse the patient's stages in the care system, from the preoperative consultation to the return home: 9 stages with 23 items rated 1 (bad) to 5 (excellent). It was sent by postmail 3 weeks after their hospitalization. RESULTS: Four hundred and sixty-seven questionnaires were mailed, with a response's rate to 38% (172/467). Participant's characteristics: 88% are women, 45% are full time workers, 54% of senology. Two-third of the assessments were rated 4 or 5. Five percent were rated 1 or 2. The patient's exit is the least preferred step. The operating room's assessment is the most preferred by patients. Sixty-one percent of participants have written a free comment, 31% are positives, 36% are negatives, and 32% are mixed. The wait was the negative recurrent comment (21%). DISCUSSION: Most participants are very satisfied. Improving the wait before the operation and output is already underway. Studies are now needed to assess the care's safety and the economic aspect of day-surgery.

Identification of new candidate therapeutic target genes in head and neck squamous cell carcinomas.

BACKGROUND: We aimed at identifying druggable molecular alterations at the RNA level from untreated HNSCC patients, and assessing their prognostic significance. METHODS: We retrieved 96 HNSCC patients who underwent primary surgery. Real-time quantitative RT-PCR was used to analyze a panel of 42 genes coding for major druggable proteins. Univariate and multivariate analyses were performed to assess the prognostic significance of overexpressed genes. RESULTS: Median age was 56 years [35-78]. Most of patients were men (80%) with a history of alcohol (70.4%) and/or tobacco consumption (72.5%). Twelve patients (12%) were HPV-positive. Most significantly overexpressed genes involved cell cycle regulation (CCND1 [27%], CDK6 [21%]), tyrosine kinase receptors (MET [18%], EGFR [14%]), angiogenesis (PGF [301%], VEGFA [14%]), and immune system (PDL1/CD274 [28%]). PIK3CA expression was an independent prognostic marker, associated with shorter disease-free survival. CONCLUSIONS: We identified druggable overexpressed genes associated with a poor outcome that might be of interest for personalizing treatment of HNSCC patients.

Experimental study of mineralization in mandibular bone distraction with irradiation during the consolidation phase.

INTRODUCTION: This study aimed at assessing the effect of radiotherapy on regenerated bone mineralization and consolidation obtained by mandibular bone distraction. The planned application was a new immediate mandibular reconstruction technique in defects following surgery for oral cavity tumours requiring postoperative radiotherapy. MATERIAL AND METHODS: Ten sheep underwent bilateral mandibular bone distraction (control group). A second group of 6 sheep (study group) had bilateral mandibular bone distraction followed by irradiation on the 21st postoperative day. The animals were sacrificed on the 60th postoperative day. Radiographic and histomorphometric studies were performed. RESULTS: In the control group, 9 distraction sites out of 20 were consolidated. In the irradiated group, 9 out of 12 were consolidated. Histomorphometric analysis did not demonstrate any statistically significant difference between the osseous and cartilaginous samples, the trabecular thickness of the new bone, or the osteoid surface of basal bone in the control and test groups (p=0.126, 0.247, 0.792, 0.082). However, the osteoid surface of the regenerated bone in the test group was statistically smaller (p=0.017) than in the control group. CONCLUSION: In this experiment, radiotherapy did not hinder bone mineralization or consolidation following distraction of mandibular bone receiving irradiation on the 21st postoperative day. Bone distraction could be proposed for the repair of mandibular defects following surgery for oral tumours which require early postoperative radiotherapy.

[Epidemiology, diagnosis and treatment of head and neck cancers]. / Épidémiologie, diagnostic et traitement des cancers ORL.

Cancers of the upper aerodigestive tracts are the fourth most common cancer in France. The main risk factors are smoking and alcohol. They do not necessarily present specific signs, making their early diagnosis difficult. A change in the patient's general condition is a late sign leading to a poor prognosis of the disease.

Mature cytotoxic CD56(bright)/CD16(+) natural killer cells can infiltrate lymph nodes adjacent to metastatic melanoma.

Melanomas are characterized by high metastatic potential, with regional lymph node representing the most frequent site of early dissemination in this disease. These regional lymph nodes also represent the primary site for differentiation of natural killer (NK) cells. Although blood-derived NK cells can efficiently lyse melanoma cells isolated from metastatic lymph node (M-LN), there has been no study of the properties of the most disease-relevant NK cells isolated from M-LN in patients with melanoma. Here, we report that M-LN contains 0.5% to 11% of CD56(bright) NK cells among CD45(+) hematopoietic cells present and that this cell population surrounds tumor cell clusters in M-LN. This NK cell population was characterized by expression of CD62L, chemokine receptors, and high levels of natural cytotoxicity receptors (NCR), NK group 2 D (NKG2D), and DNAX accessory molecule 1 (DNAM-1). Expression of NCR-NKp30 and NKG2D correlated negatively with percentages of tumor cells in M-LN. Interestingly, M-LN contained a unique subset of mature CD56(bright)CD16(+) NK cells displaying coregulated expression of NCR and NKG2D activating receptors. Ex vivo analyses suggested that M-LN-derived NK cells were inactive but could be activated by appropriate cytokine signals [interleukin (IL)-2 or IL-15], and could lyse metastatic melanoma cells in a highly efficient manner compared with blood-derived NK cells. Taken together, the results offer evidence that adjuvant immunotherapy that targets NK cells in M-LN for activation may improve treatment of patients with sentinel lymph node-positive melanoma.

Latissimus dorsi free flap reconstruction of anterior skull base defects.

INTRODUCTION: Surgery of extensive skull base tumour results of a defect of soft and hard tissue and dura. Free flap reconstruction provides tissue to restore the defect and separate the intracranial content from the bacterial flora of the nasal fossae. Vertical and transverse rectus abdominis myocutaneous free flap are usually used. This study was designed to compare our experience of latissimus dorsi free flap reconstruction of extensive skull base defects after tumour resection with the literature concerning the use of other types of free flaps. MATERIAL AND METHOD: All extensive skull base tumour resections with latissimus free flap reconstruction made in the head and neck oncology unit of the Institut Curie, Cancer Centre, between January 2004 and December 2009 were reviewed. RESULTS: Two infectious complications were observed (11.7%), two cases of CSF leak (11.7%), one case of wound dehiscence following tumour resection comprising the nasal skin (5.9%) and one case of partial distal necrosis of the flap in a zone of skin resection (5.9%) were observed. No flaps were lost. Two latissimus dorsi donor site haematomas were observed (11.7%). CONCLUSION: When reconstruction of extensive skull base defect need free flap, the latissimus dorsi free flap is a reliable solution.

Peroxisome proliferator-activated receptor-γ in mobile tongue squamous cell carcinoma: associations with clinicopathological parameters and patients survival.

PURPOSE: Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a ligand-activated transcription factor, implicated in various aspects of cancer biology, such as differentiation, proliferation, invasion and angiogenesis. The present study aimed to evaluate the clinical significance of PPAR-γ in mobile tongue squamous cell carcinoma (SCC). METHODS: PPAR-γ protein expression was assessed immunohistochemically on 49 mobile tongue SCC tissue samples obtained from an equal number of patients. PPAR-γ expression and intensity of immunostaining were statistically analyzed in relation with clinicopathological characteristics, mitotic index and patients' survival. RESULTS: Elevated PPAR-γ expression was more frequently observed in patients with reduced depth of invasion (P = 0.0111). Moderate/intense PPAR-γ staining intensity was more frequently observed in patients with no evidence of muscular infiltration (P = 0.0229) and reduced depth of invasion (P = 0.0176). Mobile tongue SCC patients presenting enhanced PPAR-γ expression had significantly longer overall and disease-free survival times compared to those with low PPAR-γ expression (log-rank test, P = 0.0162 and P = 0.0114, respectively). CONCLUSIONS: PPAR-γ immunoreactivity in mobile tongue SCC was correlated with clinicopathological characteristics crucial for patients' management and prognosis. PPAR-γ may be considered as a useful prognostic marker in mobile tongue SCC and a potential therapeutic target for tongue cancer chemoprevention and treatment.

Progressive upregulation of PD-1 in primary and metastatic melanomas associated with blunted TCR signaling in infiltrating T lymphocytes.

Programmed death-1 (PD-1) is involved in T-cell tolerance to self-antigens. For some cancers, it has been suggested that the expression of a ligand of PD-1, namely PD-L1, could contribute to tumor escape from immune destruction. Nevertheless, the relationship between PD-1 expression on tumor-infiltrating T lymphocytes (TILs), disease stage, and TIL responsiveness is still poorly documented. In this study, we show that freshly isolated CD4(+) and CD8(+) TILs express substantial levels of PD-1 in primary melanomas. The expression of PD-1 was further increased at later stages in distant cutaneous metastases, especially on CD8(+) TILs. The expression of PD-1 ligands was frequent only in metastases, on both tumor cells and tumor-derived myeloid cells. TILs isolated from these cutaneous tumors are poorly reactive ex vivo, with blunted calcium response and IFN-γ production after TCR stimulation. Surprisingly, in distinct parts of a primary melanoma, either invasive or regressing, we show that TILs similarly express PD-1 and remain dysfunctional. The expressions of PD-1 and PD-L1 in metastatic melanoma lesions could be considered as witnesses of an unsuccessful anti-tumoral immune response, but the direct involvement of PD-1 in the severity of the disease, and the importance of TILs in tumor regression, remain to be established.