ABSTRACT
ABSTRACT: Mucinous rectal cancer (MRC) is defined by the World Health Organization as an adenocarcinoma with greater than 50% mucin content. Classic teaching suggests that it carries a poorer prognosis than conventional rectal adenocarcinoma. This poorer prognosis is thought to be related to mucin dissecting through tissue planes at a higher rate, thus increasing the stage of disease at presentation. Developments in immunotherapy have bridged much of this prognostic gap in recent years. Magnetic resonance imaging is the leading modality in assessing the locoregional spread of rectal cancer. Mucinous rectal cancer carries unique imaging challenges when using this modality. Much of the difficulty lies in the inherent increased T2-weighted signal of mucin on magnetic resonance imaging. This creates difficulty in differentiating mucin from the adjacent background fat, making the detection of both the primary disease process as well as the locoregional spread challenging. Computed tomography scan can act as a valuable companion modality as mucin tends to be more apparent in the background fat. After therapy, diagnostic challenges remain. Mucin is frequently present, and distinguishing cellular from acellular mucin can be difficult. In this article, we will discuss each of these challenges and present examples of such situations and strategies that can be used to overcome them.
ABSTRACT
INTRODUCTION: This study investigated the efficacy and safety of neoadjuvant chemotherapy for locally advance penile squamous cell carcinoma for which current evidence is lacking. METHODS: Included patients had locally advanced penile squamous cell carcinoma with clinical lymph node metastasis treated with at least 1 dose of neoadjuvant chemotherapy prior to planned consolidative lymphadenectomy. Objective response rates were assessed using Response Evaluation Criteria in Solid Tumors v1.1. The primary and secondary outcomes were overall survival and progression-free survival, estimated by the Kaplan-Meier method. Treatment-related adverse events were graded per the Common Terminology Criteria for Adverse Events v5.0. RESULTS: A total of 209 patients received neoadjuvant chemotherapy for locally advanced and clinically node-positive penile squamous cell carcinoma. The study population consisted of 7% of patients with stage II disease, 48% with stage III, and 45% with stage IV. Grade 2 treatment-related adverse events occurred in 35 (17%) patients, and no treatment-related mortality was observed. Of the patients, 201 (97%) completed planned consolidative lymphadenectomy. During follow-up, 106 (52.7%) patients expired, with a median overall survival of 37.0 months (95% confidence interval [CI] = 23.8 to 50.1 months) and median progression-free survival of 26.0 months (95% CI = 11.7 to 40.2 months). Objective response rate was 57.2%, with 87 (43.2%) having partial response and 28 (13.9%) having a complete response. Patients with objective response to neoadjuvant chemotherapy had a longer median overall survival (73.0 vs 17.0 months, P < .01) compared with those who did not. The lymph node pathologic complete response rate was 24.8% in the cohort. CONCLUSION: Neoadjuvant chemotherapy with lymphadenectomy for locally advanced penile squamous cell carcinoma is well tolerated and active to reduce the disease burden and improve long-term survival outcomes.