Keratoacanthoma or cutaneous squamous cell carcinoma revealing a DNA mismatch repair default (Muir-Torre Syndrome)

Keratoacanthoma (KA) and well-differentiated cutaneous squamous cell carcinoma (cSCC) are hardly distinguishable clinically and histologically. They both can be seen in patients with hereditary non-polyposis colorectal cancer (HNPCC) or Lynch Syndrome, corresponding to DNA microsatellite instability. In our case, a young man had the excision of two rapidly growing skin tumours for which distinction between KA and cSCC was initially clinically and pathologically challenging. The diagnosis of well-differentiated cSCCs was made and the patient was treated with surgery. Ten years after the first cSCC, he was diagnosed with Muir-Torre syndrome, a variant of Lynch syndrome, with an heterozygote mutation of the MSH2 gene. This later diagnosis allowed to screen his family members for the same mutation and to adopt an appropriate follow-up regarding the risk of digestive tumours for him and his family. Furthermore, it is important to know that, in case of non-resectable cSCC occurring in this patient, immunotherapy using anti-PD1 antibody would probably be effective due to the known increased immunogenicity of MMR deficient tumours.

Sentinel lymph node biopsy in cutaneous head and neck melanoma

PURPOSE

Sentinel lymph node biopsy (SLNB) is now a standard of care for cutaneous melanoma, but it is still controversial for cutaneous head and neck melanoma (CHNM). This study aims to confirm the feasibility, accuracy and low morbidity of SLNB in CHNM and evaluate its prognostic value.

METHODS

A monocentric and retrospective study on patients with CHNM treated in our tertiary care center (Gustave Roussy) between January 2008 and December 2012 was performed. The feasibility, morbidity and prognostic value of this technique were analysed.

RESULTS

One hundred and twenty-four consecutive patients were included. SLNB was realized in 97.6% of the cases. No significant post-operative morbidity was observed. Nineteen percents of patients had a positive SN while only 14.3% of complete lymph node dissections (CLND) had additional nodal metastasis. The risk of recurrence after positive SN was significantly higher (69.2 vs 30.8%, p = 0.043). The false omission rate was low with 7.1%. Overall survival and disease-free survival were better in the negative SN group (82 vs 49%, p < 0.001 and 69.3 vs 41.8%, p = 0.0131). The risk of recurrence was significantly higher in the positive SN group (p = 0.043) and when primary tumour was ulcerated (p = 0.031). Only the mitotic rate of the primary tumour was associated with SN positivity (p = 0.049).

CONCLUSION

As in other sites, SLNB status is a strong prognostic factor with comparable false omission rate and no superior morbidity.

Baseline gut microbiota predicts clinical response and colitis in metastatic melanoma patients treated with ipilimumab

Background

Ipilimumab, an immune checkpoint inhibitor targeting CTLA-4, prolongs survival in a subset of patients with metastatic melanoma (MM) but can induce immune-related adverse events, including enterocolitis. We hypothesized that baseline gut microbiota could predict ipilimumab anti-tumor response and/or intestinal toxicity.

Patients and methods

Twenty-six patients with MM treated with ipilimumab were prospectively enrolled. Fecal microbiota composition was assessed using 16S rRNA gene sequencing at baseline and before each ipilimumab infusion. Patients were further clustered based on microbiota patterns. Peripheral blood lymphocytes immunophenotypes were studied in parallel.

Results

A distinct baseline gut microbiota composition was associated with both clinical response and colitis. Compared with patients whose baseline microbiota was driven by Bacteroides (cluster B, n = 10), patients whose baseline microbiota was enriched with Faecalibacterium genus and other Firmicutes (cluster A, n = 12) had longer progression-free survival (P = 0.0039) and overall survival (P = 0.051). Most of the baseline colitis-associated phylotypes were related to Firmicutes (e.g. relatives of Faecalibacterium prausnitzii and Gemmiger formicilis), whereas no colitis-related phylotypes were assigned to Bacteroidetes. A low proportion of peripheral blood regulatory T cells was associated with cluster A, long-term clinical benefit and colitis. Ipilimumab led to a higher inducible T-cell COStimulator induction on CD4+ T cells and to a higher increase in serum CD25 in patients who belonged to Faecalibacterium-driven cluster A.

Conclusion

Baseline gut microbiota enriched with Faecalibacterium and other Firmicutes is associated with beneficial clinical response to ipilimumab and more frequent occurrence of ipilimumab-induced colitis.

Experience in daily practice with ipilimumab for the treatment of patients with metastatic melanoma: an early increase in lymphocyte and eosinophil counts is associated with improved survival

BACKGROUND

Ipilimumab is a recently approved immunotherapy that has demonstrated an improvement in the overall survival (OS) of patients with metastatic melanoma. We report a single-institution experience in patients treated in a compassionate-use program.

PATIENTS AND METHODS

In this prospective study, patients were treated between June 2010 and September 2011. Inclusion criteria were a diagnosis of unresectable stage III or IV melanoma, at least one previous line of chemotherapy, and survival 12 weeks after the first perfusion. Four courses of ipilimumab were administered at a dose of 3 mg/kg every 3 weeks.

RESULTS

Seventy-three patients were included. Median OS was 9.1 months (95% CI 6.4-11.3) from the start of ipilimumab. Immune-related adverse events were observed in 45 patients (62%), including 19 grade 3-4 events (26%). No drug-related death occurred. A lymphocyte count >1000/mm(3) at the start of the second course and an increase in the eosinophil count >100/mm(3) between the first and second infusions were correlated with an improved OS.

CONCLUSION

Ipilimumab toxic effect is manageable in real life. Biological data such as lymphocyte and eosinophil counts at the time of the second ipilimumab infusion appear to be early markers associated with better OS.

Sequential research-related biopsies in phase I trials: acceptance, feasibility and safety

BACKGROUND

Sequential tumour biopsies are of potential interest for the rational development of molecular targeted therapies.

PATIENTS AND METHODS

From June 2004 to July 2009, 186 patients participated in 14 phase I clinical trials in which sequential tumour biopsies (13 trials) and/or sequential normal skin biopsies (6 trials) were optional. All patients had to sign an independent informed consent for the biopsies.

RESULTS

Tumour biopsies were proposed to 155 patients and 130 (84%) signed the consent while normal skin biopsies were proposed to 70 patients and 57 (81%) signed the consent. Tumour biopsies could not be carried out in 41 (31%) of the 130 consenting patients. Tumour biopsies were collected at baseline in 33 patients, at baseline and under treatment in 56 patients. Tumour biopsies were obtained using an 18-gauge needle, under ultrasound or computed tomography guidance. Only nine minor complications were recorded. Most tumour biopsy samples collected were intended for ancillary molecular studies including protein or gene expression analysis, comparative genomic hybridization array or DNA sequencing. According to the results available, 70% of the biopsy samples met the quality criteria of each study and were suitable for ancillary studies.

CONCLUSIONS

In our experience, the majority of the patients accepted skin biopsies as well as tumour biopsies. Sequential tumour and skin biopsies are feasible and safe during early-phase clinical trials, even when patients are exposed to anti-angiogenic agents. The real scientific value of such biopsies for dose selection in phase I trials has yet to be established.

[Two cases of psoas abscesses caused by group A beta-haemolytic streptococcal infection with a cutaneous portal of entry]

BACKGROUND

Psoas abscess is a rare clinical entity that occurs chiefly after intra-abdominal or retroperitoneal infection. We report two cases of psoas abscesses caused by group A beta-haemolytic streptococcal infection having a cutaneous portal of entry.

CASE REPORTS

The first patient, a 50-year-old man, was feverish and had ulcerative and necrotic cutaneous lesions evocative of ecthyma that were progressing for three months and were recently associated with a painful mass in the left iliac fossa, leading to difficulties in walking. The second patient, a 35-year-old woman with a medical history of intravenous drug addiction, was admitted to intensive care for sepsis syndrome following group A beta-haemolytic streptococcal infection with a cutaneous portal of entry (swelling on left lower limb). She remained unaccountably subfebrile 10 days after the start of antibiotic therapy with amoxicillin. Abdominal CAT scans for each patient confirmed the diagnosis of left psoas abscess. For the first patient, the same group A beta-haemolytic streptococcus was isolated in drainage fluid and at the cutaneous injury site. The outcome was favourable in both cases following extensive intravenous antibiotic therapy (amoxicillin) combined with percutaneous drainage (in the first case).

DISCUSSION

Psoas abscess can occur after locoregional infection and the portals of entry are usually gastro-intestinal, musculoskeletal or genitourinary, with many organisms capable of causing such secondary abscesses. Psoas abscess can also be a primary clinical event. Staphylococcus aureus is the most common causative organism. The presented cases comprised secondary psoas abscesses with a cutaneous portal of entry. Since the complete set of three evocative symptoms (prolonged fever, pain and psoitis) is frequently seen late, diagnosis must be made on the basis of prolonged infectious state or unaccountable feverish abdominal pain. Diagnosis is based on abdominal CAT scan and treatment involves the use of appropriate antibiotics as well as percutaneous or surgical drainage of the abscess. The mortality rate in this patient population remains high with survival being dependent on prompt initiation of therapy.