Evaluating treatment protocols for rectal squamous cell carcinomas: the Duke experience and literature

The Enigma That is Rectal Squamous Cell Carcinoma: A Case Series

INTRODUCTION

Colorectal cancer is the third most common cancer and the third leading cause of cancer deaths in the United States. As rectal squamous cell carcinoma (SCC) is an uncommon colorectal cancer, there is limited data on this clinical entity. We aimed to evaluate the tumor characteristics, treatment, and clinical outcomes of this rare deadly disease.

METHODS

Pathological specimens from 2017 to 2022 at a single National Cancer Institute-designated cancer center were screened for all rectal cases with a diagnosis of SCC. All patients with a primary rectal SCC were included. Patients who had extension to the dentate line or evidence of an anal mass, and those who were treated at an outside institution, were excluded. Demographic, treatment, outcome, and surveillance data was extracted.

RESULTS

There were 56 specimens identified, nine of which met inclusion criteria. Most patients were White (78%), Hispanic (78%), and female (67%). The average age at diagnosis was 57 y [52-65]. All patients had nodal involvement at the time of clinical staging. All patients were treated with Nigro protocol, with one patient treated with surgery first. The median time of follow-up was 12 mo after initial treatment, 33% had recurrence, with median time to recurrence of 25 mo. Overall, mortality from rectal SCC was 33% at a median time of 37 mo from initial diagnosis.

CONCLUSIONS

Rectal SCC is a colorectal cancer that is not fully understood. Our findings showed that treatment mirrors that of anal SCC, with similar rates of survival to both rectal adenocarcinoma and anal SCC.

Treatment of metastatic rectal squamous cell carcinoma in a pregnant patient

Rectal squamous cell carcinoma is an exceedingly rare form of rectal cancer, with limited data available regarding its presentation and effective treatment. Rectal cancer occurring during pregnancy is uncommon as well. This is a case of metastatic rectal squamous cell carcinoma presenting in a 22-week pregnant, female patient in her early 30s. The patient was treated with 5-fluorouracil and cisplatin and delivered a healthy male child born via uncomplicated vaginal delivery at 35 weeks. This article demonstrates that despite the rare nature of this cancer, in the already rare context of pregnancy, effective and safe treatment is possible with a multidisciplinary team.

Case Report: Intervention of radiotherapy improves the prognosis of rectal squamous cell carcinoma with high PD-L1 expression and enable patients to obtain NED status

Background

Rectal squamous cell carcinoma (RSCC) is a rare malignancy of the rectal tumor. Due to its extremely low incidence, there is still a lack of high-level treatment evidence and clinical consensus on this disease.

Case report

In this article, we report a treatment process of RSCC with high PD-L1 expression. Firstly, this patient received 2 cycles of Pembrolizumab immunotherapy, but the efficacy was less sanguine. Subsequently, 4 cycles of mFOLFOX6 chemotherapy were synchronously performed on the basis of the initial regimen. Although partial remission was achieved in the lymph nodes thereafter, the changes in the primary lesions were still not significant. After that, the patient received radiotherapy, and followed by 6 cycles of PC (Albumin-binding Paclitaxel and Nedaplatin) regimen chemotherapy combined with Pembrolizumab. Eventually, the patient achieved no evidence of disease (NED) status, and no signs of recurrence or metastasis were found after 12 months of follow-up.

Conclusion

This is the first report of a RSCC patient with high PD-L1 expression achieving a complete response. Looking back over the whole treatment process of this patient, we found that the participation of radiotherapy was the inflection point of prominent efficacy, which may provide a new idea for the selection of comprehensive treatment strategies for patients with RSCC.

Case report of unusual synchronous anal and rectal squamous cell carcinoma: clinical and therapeutic lesson

Synchronous tumors of the rectum and anus are sporadic. Most cases in the literature are rectal adenocarcinomas with concomitant anal squamous cell carcinoma. To date, only two cases of concomitant squamous cell carcinomas of the rectum and anus are reported, and both were treated with up-front surgery and received abdominoperineal resection with colostomy. Here, we report the first case in the literature of a patient with synchronous HPV-positive squamous cell carcinoma of the rectum and anus treated with definitive chemoradiotherapy with curative intent. The clinical-radiological evaluation demonstrated complete tumor regression. After 2 years of follow-up, no evidence of recurrence was observed.

Treatment paradigm and prognostic factor analyses of rectal squamous cell carcinoma

Background

Rectal squamous cell carcinoma (rSCC) is a rare pathological subtype of rectal cancer. There is no consensus on the treatment paradigm for patients with rSCC. This study aimed to provide a paradigm for clinical treatment and develop a prognostic nomogram.

Methods

Patients diagnosed with rSCC between 2010 and 2019 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. According to the TNM staging system, Kaplan-Meier (K-M) survival analysis was used to identify the survival benefits of different treatments in patients with rSCC. The Cox regression method was used to identify independent prognostic risk factors. Nomograms were evaluated by Harrell's concordance index (C-index), calibration curves, decision curve analysis (DCA) and K-M curves.

Results

Data for 463 patients with rSCC were extracted from the SEER database. Survival analysis showed that there was no significant difference in median cancer-specific survival (CSS) among patients with TNM stage 1 rSCC treated with radiotherapy (RT), chemoradiotherapy (CRT) or surgery (P = 0.285). In TNM stage 2 patients, there was a significant difference in median CSS among those treated with surgery (49.5 months), RT (24 months), and CRT (63 months) (P = 0.003). In TNM stage 3 patients, there was a significant difference in median CSS among those treated with CRT (58 months), CRT plus surgery (56 months) and no treatment (9.5 months) (P < 0.001). In TNM stage 4 patients, there was no significant difference in median CSS among those treated with CRT, chemotherapy (CT), CRT plus surgery and no treatment (P = 0.122). Cox regression analysis showed that age, marital status, T stage, N stage, M stage, PNI, tumor size, RT, CT, and surgery were independent risk factors for CSS. The 1-, 3-, and 5-year C-indexes were 0.877, 0.781, and 0.767, respectively. The calibration curve showed that the model had excellent calibration. The DCA curve showed that the model had excellent clinical application value.

Conclusion

RT or surgery is recommended for patients with stage 1 rSCC, and CRT is recommended for patients with stage 2, and stage 3 rSCC. Age, marital status, T stage, N stage, M stage, PNI, tumor size, RT, CT, and surgery are independent risk factors for CSS in patients with rSCC. The model based on the above independent risk factors has excellent prediction efficiency.

Atypical mid rectal localization of squamous cell carcinoma: A case report and literature review

INTRODUCTION AND IMPORTANCE

Squamous cell carcinoma occurring in the rectum is a very rare malignancy. When encountered in the gastrointestinal tract, it usually involves the esophagus or the anal canal. The rare incidence of rectal squamous cell carcinomas has raised quite a few questions on the hypothetical etiologies and prognosis.

CASE PRESENTATION

In this report, we present a case of a 73 years old woman who presented a rare case of squamous cell carcinoma, at 8 cm from the anal margin.

CLINICAL DISCUSSION

Optimal treatment sequence of such an uncommon disease is yet to be standardized, surgery was the gold standard management for rectal squamous cell carcinoma, but exclusive chemoradiotherapy is slowly but surely supplanting it.

CONCLUSION

This case allows us to engage in discussions over the uncommon location of the rectal SCC and its current treatment management. The exclusive chemoradiation therapy has given excellent results becoming the gold standard treatment of this rare entity.

Modified DCF (Docetaxel, Cisplatin and 5-fluorouracil) chemotherapy is effective for the treatment of advanced rectal squamous cell carcinoma

Background

Advanced rectal squamous cell carcinoma (rSCC) is a very rare and aggressive entity, and the best initial management is crucial for long survival as well as organ preservation and quality of life. Whereas local diseases are treated with chemo-radiotherapy and salvage surgery, data are scarce on how to treat more advanced diseases, and the role of induction chemotherapy is unknown.

Methods

We retrospectively analyzed all consecutive patients with advanced rSCC and treated with modified DCF (docetaxel, cisplatin, 5-fluorouracil; mDCF) regimen, from January 2014 and December 2021 in two French centers. Exploratory endpoints were efficacy (overall survival, recurrence-free survival, response rate, organ preservation rate) and safety.

Results

Nine patients with locally advanced or metastatic diseases received a mDCF regimen and were included for analysis. The median age was 62.0 years, 7 patients (77.8%) were women, and all eight available tumors were positive for HPV, mostly (85.7%) to genotype 16. With a median follow-up of 33.1 months, 77.8% of patients were still alive and disease-free, and the median overall survival was not reached at six years. The objective response rate was 87.5% after mDCF, and the complete response rate was 25.0% after mDCF and was increased to 75.0% after chemoradiotherapy. Only one patient underwent surgery on the primary tumor, with a complete pathological response. The median mDCF cycle was eight over eight scheduled, and all patients received the complete dose of radiotherapy without interruptions.

Conclusions

Induction mDCF chemotherapy followed by chemoradiotherapy is safe and highly effective in patients with advanced rSCC, and should be considered as an option in metastatic stage or locally advanced disease with an organ-preservation strategy.

A Rare Case of Primary Rectal Squamous Cell Carcinoma and the Use of Cytokeratin Markers

Lower gastrointestinal cancers are commonly adenocarcinoma of the colon and rectum and squamous cell carcinoma (SCC) of the anus. Rectal squamous cell carcinoma (SCC) is a rare gastrointestinal tract malignancy, as rectal SCC is assumed to be from the migration of anal squamous cells. However, primary rectal SCC is rarer. Here, we present a case of a 63-year-old male who was found to have rectal SCC that was very close to the anus. Through literature review, it was noted that SCC and adenocarcinoma of rectal origin stain positive for cytokeratin CAM 5.2 and not the anal canal lesions. This patient's tumor was positive for CAM 5.2. The patient was treated with 5-fluorouracil and mitomycin C with radiation therapy for five weeks. The post-therapy repeat PET scan showed complete resolution of the tumor and oligometastasis. Unfortunately, the 20-week follow-up PET CT showed para-aortic and retrocrural lymph nodes consistent with malignancy. This case emphasizes the use of immunohistochemical stains for diagnosis and treatment planning in patients with rectal SCC. Once the diagnosis was confirmed, the patient was treated as anal SCC. The importance of differentiating between rectal and anal SCC can be argued, although the treatment is the same; however, the prognosis is worse based on nodal involvement in rectal SCC. Patients with early intervention have a five-year overall disease-free survival of greater than 80%.

Squamous rectal carcinoma: a rare malignancy, literature review and management recommendations

Squamous cell carcinoma of the rectum is a rare malignancy (0.3% of all rectal cancers), with no known risk factor. These tumours are assessed as rectal cancer using immunohistochemical and radiological tests, and certain criteria (localisation, relationship with neighbouring structures) have to be fulfilled to make the diagnosis. Some clinicians used to stage them with the anal cancer TNM (tumour–node–metastasis), whereas others used the rectal cancer TNM. When localised, the tendency nowadays is to treat those tumours like squamous anal cancers with definitive chemoradiotherapy (5-fluorouracil and mitomycin) and to skip surgery. For metastatic disease there is no clearly validated regimen and treatment should be based on recommendations of squamous anal cancers because of their common histology. Concerning follow-up after a curative approach, techniques should follow those for anal cancer as well, evaluating a delayed response.

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Rectal squamous cell carcinoma (rSCC) is a rare entity for which we have limited knowledge and no clear recommendations.

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Creation of an international registry and a biological repository could increase our understating of this rare entity.

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Definitive chemoradiotherapy (CRT) should be the gold standard treatment of local/locally-advanced rSCC.

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Clarification of clinical and pathologic response rates with CRT or radiotherapy alone and patterns of failure is important.

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Timing for tumour response assessment is paramount. Data tilt towards waiting until 6 months after definitive treatment.

Rectal Squamous Cell Cancer

Squamous cell carcinoma occurring in the rectum is one of the rare malignancies that has been discovered. Most squamous cell carcinomas that surface in the gastrointestinal tract tend to occur in either the esophagus or the anal canal. However, the rare incidence of rectal squamous cell carcinomas has raised quite a few questions on the hypothetical etiologies, prognosis, and optimal treatment sequence of such a disease course in modern medicine. In this report, we present the case of a 63-year-old gentleman who came to the clinic with change in bowel habits such as constipation and bright red blood in his stool. Colonoscopy revealed a 4.1 cm polyp in the distal rectum, which upon biopsy was confirmed to be a well-differentiated keratinizing squamous cell carcinoma. This case allows us to engage in discussions over potential etiologies and current treatment management for such a rare malignancy.