Impact of DNA mismatch repair proteins deficiency on number and ratio of lymph nodal metastases in colorectal adenocarcinoma

BACKGROUND

Approximately 15 % of colorectal adenocarcinomas (CRCs) are characterized by an altered expression of DNA mismatch repair (MMR) proteins (i.e. MMR deficiency [MMRd]). Lymph node ratio (LNR) represents one of the most important prognostic markers in non-advanced CRCs. No significant data are available regarding LNR distribution depending on MMR status.

PURPOSE OF THE STUDY

The aim of the present work was to compare pathological and clinical characteristics of MMRd tumors versus MMR proficient (MMRp) cases. Particular attention was paid to how these molecular sub-groups relate to the LNR.

MATERIALS AND METHODS

A mono-Institutional series of 1037 consecutive surgically treated stage I-IV CRCs were retrospectively selected and data were obtained from pathological reports. Cases were characterized for MMR/MSI status by means of immunohistochemistry or for microsatellite instability (MSI) analysis.

RESULTS

MMRd/MSI tumors (n = 194; 18.7 %) showed significant differences in comparison to MMRp lesions for sex (female prevalence 50.5 % vs 40.7 %; p = 0.013), age (74.2 vs 69.2; p < 0.001), location (right side; p < 0.001), diameter (larger than MMRp; p < 0.001), growth pattern (expansive pattern of growth; p < 0.001), peri- (p = 0.0002) and intra-neoplastic (p = 0.0018) inflammatory infiltrate, presence of perineural invasion (p < 0.001), stage (lower stage at presentation; p < 0.001), grade (higher prevalence of high-grade tumors; p < 0.001), and LNR (lower; p < 0.001).

CONCLUSIONS

MMRd/MSI tumors are a distinct molecular CRC subtype characterized by a significantly lower LNR in comparison to MMRp lesions. These data further support the prognostic impact of MMRd/MSI status in early-stage CRCs.

Extramammary Paget's Disease of the Vulva and Concomitant Premalignant/Malignant Vulvar Lesions: A Potential Challenge in Diagnosis and Treatment

The aim of the present study was to evaluate the incidence of concomitant vulvar cancers or premalignant lesions in women surgically treated for extramammary Paget's disease of the vulva (EMPDV) through a multicenter case series. The medical records of all women diagnosed with and treated for EMPDV from January 2010 to December 2020 were retrospectively analyzed. Women with EMPDV and synchronous vulvar cancer, vulvar intraepithelial neoplasia (VIN) and/or lichen sclerosus (LS) at the histology report were included in the study. A total of 69 women eligible for the present study were considered. Concomitant vulvar lesions occurred in 22 cases (31.9%). A total of 11 cases of synchronous VIN (50%) and 14 cases (63.6%) of concomitant LS were observed. One patient (4.5%) had synchronous vulvar SCC (FIGO stage 1B). Women with EMPDV and concomitant premalignant/malignant vulvar lesions had a significantly higher rate of invasive EMPDV and wider lesions with an extravulvar involvement. The specific meaning of the association between EMPDV, VIN, SCC and LS remains unclear. The potential overlapping features between different vulvar lesions highlight the importance of dedicated gynecologists and pathologists in referral centers.

Safety and efficacy of the combination carboplatin and paclitaxel in patients (pts) with recurrent head and neck squamous cell carcinoma (HNSCC)

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Background: Pts with recurrent HNSCC have a dismal prognosis; treatment options are poorly effective and burdened with toxicity. In this clinical setting, cisplatin and paclitaxel have demonstrated activity despite relevant side effects. The purpose of this phase II trial was to investigate whether a combination of carboplatin and paclitaxel could offer a better toxicity profile without affecting efficacy. Methods: Pts with bi-dimensionally measurable disease, previously treated with induction chemotherapy (Cisplatin and 5-FU) followed by concomitant chemo-radiotherapy, were studied. Treatment consisted of Carboplatin AUC 5 and Paclitaxel 175 mg/m2 intravenously every 3 weeks. G-CSF and darbepoetin alpha were allowed in case of neutropenia (N < 1000/mm3) or anemia (Hb < 11 g/dL). Pts were evaluated for toxicity and response. Results: So far, 15 pts were enrolled. Median age was 53 yrs; ECOG P.S. was 0–1. Site of disease at relapse was head and neck excluding lips and sinus; 12 out of 15 pts had stage IV disease. All pts were evaluated for response and toxicity. After three cycles of chemotherapy, we observed 1 complete response (6.6%) and 7 partial responses (46.6%), with a 53.2 % overall response rate (95% CI 26.6–78.7%). Stable disease was seen in 2 patients (13.3%) and progressive disease was observed in 5 pts (33.3%). Toxicity was mild: we recorded 1 case of G3 toxicity (neutropenia) and no G4 side effects. Three pts experienced G1–2 neuropathy and 4 pts G1–2 hematologic toxicity (neutropenia and thrombocytopenia). Conclusions: The current regimen was feasible and effective. The combination of Carboplatin and Paclitaxel was well tolerated and could be safely administered to pts with recurrent HNSCC as second line treatment. Enrollment and data collection are still ongoing.

No significant financial relationships to disclose.