Factors associated with pathologic complete response following neoadjuvant chemoradiation and esophagectomy for carcinoma of esophagus and gastroesophageal junction.

BACKGROUND AND OBJECTIVES: The aim of this study was to analyze factors associated with pathologic complete response (pCR) following neoadjuvant chemoradiation (NCRT) and esophagectomy for carcinoma of the esophagus (EC) and gastroesophageal junction (GEJ). METHODS: Patients with EC and GEJ tumors who received NCRT and underwent esophagectomy between January 2010 to March 2021 were included. Univariate and multivariate analyses were performed to evaluate the factors associated with pCR by comparing the patients who achieved pCR (pCR group) with those who did not achieve pCR (non-pCR group). RESULTS: A total of 321 patients were included in the study, with squamous cell carcinoma (SCC) accounting for the majority of cases (76%). One hundred and sixty (49.8%) patients had pCR. SCC histology and pretreatment radiographic node-negative status (cN0) were associated with pCR. Patients in the pCR group had significantly better overall and disease-free survival compared with patients in the non-pCR group. CONCLUSIONS: SCC histology and pretreatment radiographic node-negative status were associated with pCR. For patients with tumors of EC and GEJ who received NCRT and underwent esophagectomy, pCR was associated with improved prognosis compared with those not achieving pCR.

Evidence for possible non-canonical pathway(s) driven early-onset colorectal cancer in India.

Two genetic instability pathways viz. chromosomal instability, driven primarily by APC mutation induced deregulated Wnt signaling, and microsatellite instability (MSI) caused by mismatch repair (MMR) inactivation, together account for >90% of late-onset colorectal cancer (CRC). Our understanding of early-onset sporadic CRC is however comparatively limited. In addition, most seminal studies have been performed in the western population and analyses of tumorigenesis pathway(s) causing CRC in developing nations have been rare. We performed a comparative analysis of early and late-onset CRC from India with respect to common genetic aberrations including Wnt, KRAS, and p53 (constituting the classical CRC progression sequence) in addition to MSI. Our results revealed the absence of Wnt and MSI in a significant proportion of early-onset as against late-onset CRC in India. In addition, KRAS mutation frequency was significantly lower in early-onset CRC indicating that a significant proportion of CRC in India may follow tumorigenesis pathways distinct from the classical CRC progression sequence. Our study has therefore revealed the possible existence of non-canonical tumorigenesis pathways in early-onset CRC in India.

Distinct genetic aberrations in oesophageal adeno and squamous carcinoma.

BACKGROUND: The two main oesophageal cancer subtypes namely adenocarcinoma and squamous cell carcinoma exhibit interesting clinical, pathological and geographical variations with the former being more common in the West and the latter in Asia. MATERIALS AND METHODS: We evaluated status of p53, EGFR, Wnt and HPV in addition to microsatellite instability and loss of heterozygosity of several chromosomal loci in the two oesophageal cancer subtypes from India. The comparative analysis was extended to two oesophageal adenosquamous mixed cancer samples. RESULTS: Our results reveal a high frequency of EGFR overexpression in ESCC as against EAC, while Wnt activation was a significantly more common event in EAC as against ESCC. Frequencies of p53 perturbations were not significantly different in the two subtypes. Interestingly, the EGFR and Wnt status in adenocarcinoma and squamous components of the two oesophageal adenosquamous cancer samples were identical to primary tumours. In addition, no common molecular aberration (including instability and loss of heterozygosity) in several microsatellites was detected in DNA isolated from the two components in both adenosquamous cancer samples. CONCLUSIONS: Our results reveal the presence of distinct aberrations in oesophageal adenocarcinoma and squamous cell carcinoma which are replicated in the respective components of adenosquamous cancers. The study therefore suggests perhaps an independent origin of the two components of oesophageal adenosquamous mixed cancer.

Blumer's Shelf on Laparoscopy.

Blumer's shelf indicates metastatic tumor deposit in rectouterine, or rectovesical pouch on digital rectal or vaginal examination, frequently from stomach, pancreatic, colon, or lung cancer. It underscores the need to carry out  a thorough clinical examination. Though it is much discussed and described in the literature, there are hardly any article or image about its appearance  on laparoscopy. We describe a case  of gastric cancer with Blumer's shelf and its appearance on laparoscopy with clinical and radiological correlation.

The Value of Lymphadenectomy Post-Neoadjuvant Therapy in Carcinoma Esophagus: a Review.

Lymph nodal metastasis is one of the most important prognostic factors determining survival in patients with carcinoma esophagus. Radical esophagectomy, with the resection of surrounding lymph nodes, is considered the prime treatment of carcinoma esophagus. An extensive lymphadenectomy improves the accuracy of staging and betters locoregional control, but its effect on survival is still not apparent and carries the disadvantage of increased morbidity. The extent of lymphadenectomy during esophagectomy also remains debatable, with many studies revealing contradictory results, especially in the era of neoadjuvant therapy. The pattern of distribution and the number of nodal metastasis are modified by neoadjuvant therapy. The paper reviews the existing evidence to determine whether increased lymph node yield improves oncological outcomes in patients undergoing esophagectomy with particular attention to those patients receiving neoadjuvant therapy.