Adenoid Cystic Carcinoma/Basal Cell Carcinoma of the Prostate: Overview and Update on Rare Prostate Cancer Subtypes

Failure to progress: breast and prostate cancer cell lines in developing targeted therapies

Developing anticancer drugs from preclinical to clinical takes approximately a decade in a cutting-edge biomedical lab and still 97% of most fail at clinical trials. Cell line usage is critical in expediting the advancement of anticancer therapies. Yet developing appropriate cell lines has been challenging and overcoming these obstacles whilst implementing a systematic approach of utilizing 3D models that recapitulate the tumour microenvironment is prudent. Using a robust and continuous supply of cell lines representing all ethnic groups from all locales is necessary to capture the evolving tumour landscape in culture. Next, the conversion of these models to systems on a chip that can by way of high throughput cytotoxic assays identify drug leads for clinical trials should fast-track drug development while markedly improving success rates. In this review, we describe the challenges that have hindered the progression of cell line models over seven decades and methods to overcome this. We outline the gaps in breast and prostate cancer cell line pathology and racial representation alongside their involvement in relevant drug development.

Tislelizumab: An effective anti-PD-1 antibody for the treatment of advanced basal cell carcinoma of the prostate

Basal cell carcinoma (BCC) of the prostate is a rare and enigmatic tumor with uncertain biological behavior and treatment modalities. Some studies suggest that BCC exhibits invasive characteristics and a high degree of malignancy, necessitating proactive management and vigilant monitoring. Notably, there is a lack of reported effective treatment utilizing programmed cell death protein-1 (PD-1) inhibitors for advanced BCC of the prostate. This study explores the efficacy of tislelizumab, as a single-agent therapy, in the successful treatment of advanced prostate BCC.

Adenoid cystic/basal-cell carcinoma of the prostate following high-grade urothelial bladder cancer: a case report

Adenoid cystic/Basal-cell carcinoma (ACC/BCC) of the prostate is a rare histological type exhibiting various morphological characteristics and an optimal treatment has not yet been established. We report the case of a 63-year-old patient who complained of incomplete bladder emptying and recurrent urinary infection six months after transurethral resection of a high-grade urothelial bladder tumor. The clinical features, digital rectal examination, serum PSA levels, and multiparametric MRI did not refer to any suspicious prostatic lesions and cystoscopy revealed bladder neck hypertrophy, and yellowish zones in the prostatic urethra. Transurethral resection was performed due to these findings and histopathological analysis showed poorly differentiated ACC/BCC of the prostate. Even though there is no proven mutual correlation between ACC/BCC and urothelial bladder cancer, the appearance of obstructive urinary symptoms, bladder-neck hypertrophy, and macroscopic changes in prostatic urethra should be reconsidered for transurethral resection biopsy considering the possibility of ACC/BCC.

Cystic Pelvic Masses in Men: A Presentation of Uncommon Cases and a Literature Review

Unclear cystic masses in the pelvis in male patients are a rare situation and could be of benign or malignant origin. The underlying diseases demand for specific diagnostic and therapeutic approaches. We present a case series of 3 male patients with different clinical symptoms (perineal pain, urinary retention and a large scrotal cyst) related to cystic lesions in the pelvic region. On all patients initial histopathological workup was unclear. All patients underwent surgery with complete resection of the tumor which revealed a broad spectrum of histopathological findings: unusual form of cystic adenocarcinoma of the prostate, malignant transformation of a dysontogenetic cyst, and finally a very rare diagnosis of a malignant tumor of the Cowper gland. This case series and literature review provide clues for a possible diagnostic and therapeutic approach in the case of unclear pelvic cystic masses and could support urologists during the therapy selection in the future.

A case of metastatic adenoid cystic (basal cell) carcinoma of the prostate: Systemic therapy for a rare disease

BACKGROUND

Metastatic adenoid cystic (basal cell) carcinoma of the prostate is an exceedingly rare disease entity. As a result, no current consensus exists for optimal systemic therapy.

METHODS

We present a patient with metastatic adenoid cystic (basal cell) carcinoma of the prostate who subsequently received systemic treatment, including chemotherapy and immunotherapy. We comprehensively reviewed all published data on therapy outcomes in advanced disease.

RESULTS

Our patient benefited from combination chemotherapy (carboplatin and paclitaxel), with objective radiographic response and reduction in cancer-related pain. However, chemotherapy was stopped due to cumulative neurotoxicity, and subsequent immunotherapy with atezolizumab did not produce any response. Our literature review revealed inconsistent outcomes with various treatments but showed most promise with chemotherapy. Targeted therapy and immunotherapy seem to benefit specific cases, and androgen deprivation therapy had minimal evidence of benefit.

CONCLUSION

Based on the findings of our case report and literature review, we suggest platinum-based chemotherapy doublets as first-line treatment for metastatic cases of adenoid cystic (basal cell) carcinoma of the prostate, reserving targeted therapy or immunotherapy for select cases based upon molecular profiles.

Basal cell carcinoma of the prostate with squamous metaplasia: A case report and literature review

Basal cell carcinoma of the prostate (BCCP) is a rare tumor with a total incidence of 140 cases to date. However, BCCP with squamous metaplasia has not been reported as of date. In this paper, we report the first case of BCCP with squamous metaplasia. The patient was hospitalized for progressive dyspareunia and had been treated for recurrent urinary retention four times in 5 years. Rectal examination showed that the prostate was medium in texture with no palpable nodules. The levels of total prostate specific antigen (tPSA), free prostate specific antigen (fPSA), and fPSA/tPSA (f/t) ratio were 1.29 ng/mL, 0.4 ng/mL, and 0.31, respectively. Ultrasound of the urinary tract showed that the prostate gland was 51 mm*40 mm*38 mm in size. We performed transurethral resection of the prostate. Histopathology confirmed the diagnosis of basal cell carcinoma with focal squamous differentiation, and immunohistochemical staining was positive for P63 and 34βE12. A laparoscopic radical prostatectomy was performed 45 days after the first surgery and the postoperative pathology showed a small amount of residual tumor with negative margins and no involvement of the seminal vesicles and vas deferens. The patient was followed up for 50 months and was doing well by the end of our study. We describe the clinical symptoms, pathological features, treatment, and prognosis of patients with BCCP with squamous metaplasia. The relevant published literature is also briefly reviewed.

Moderately Hypofractionated Helical Tomotherapy for Prostate Cancer: Ten-year Experience of a Mono-institutional Series of 415 Patients

BACKGROUND/AIM

Radiotherapy represents an important therapeutic option in the management of prostate cancer (PCa). As helical tomotherapy may improve toxicity outcomes, we aimed to evaluate and report the toxicity and clinical outcomes of localized PCa patients treated with moderately hypofractionated helical tomotherapy.

PATIENTS AND METHODS

We retrospectively analyzed 415 patients affected by localized PCa and treated with moderately hypofractionated helical tomotherapy in our department from January 2008 to December 2020. All patients were stratified according to the D'Amico risk classification: low-risk 21%, favorable intermediate-risk 16%, unfavorable intermediate-risk 30.4%, and high-risk 32.6%. The dose prescription for high-risk patients was 72.8 Gy to the prostate (planning tumor volume-PTV1), 61.6 Gy to the seminal vesicles (PTV2), and 50.4 Gy to the pelvic lymph nodes (PTV3) in 28 fractions; for low- and intermediate-risk patients 70 Gy for PTV1, 56 Gy for PTV2, and 50.4 Gy for PTV3 in 28 fractions. Image-guided radiation therapy was performed daily in all patients by mega-voltage computed tomography. Forty-one percent of patients received androgen deprivation therapy (ADT). Acute and late toxicity was assessed according to the National Cancer Institute's Common Terminology Criteria for Adverse Events v.5.0 (CTCAE).

RESULTS

Median follow-up was 82.7 months (range=12-157 months) and the median age of patients at diagnosis was 72.5 years (range=49-84 years). The 3, 5, and 7 yr overall survival (OS) rates were 95%, 90%, and 84%, respectively, while 3, 5, and 7 yr disease-free survival (DFS) were 96%, 90%, and 87%, respectively. Acute toxicity was as follows: genitourinary (GU) G1 and G2 in 35.9% and 24%; gastrointestinal (GI) in 13.7% and 8%, with G3 or more acute toxicities less than 1%. The late GI toxicity G2 and G3 were 5.3% and 1%, respectively, and the late GU toxicity G2 and G3 were 4.8% and 2.1%, respectively, and only three patients had a G4 toxicity.

CONCLUSION

Hypofractionated helical tomotherapy for PCa treatment appeared to be safe and reliable, with favorable acute and late toxicity rates and encouraging results in terms of disease control.

Linac-based stereotactic salvage reirradiation for intraprostatic prostate cancer recurrence: toxicity and outcomes

BACKGROUND

The rates of local failure after curative radiotherapy for prostate cancer (PC) remain high despite more accurate locoregional treatments available, with one third of patients experiencing biochemical failure and clinical relapse occurring in 30-47% of cases. Today, androgen deprivation therapy (ADT) is the treatment of choice in this setting, but with not negligible toxicity and low effects on local disease. Therefore, the treatment of intraprostatic PC recurrence represents a challenge for radiation oncologists. Prostate reirradiation (Re-I) might be a therapeutic possibility. We present our series of patients treated with salvage stereotactic Re‑I for intraprostatic recurrence of PC after radical radiotherapy, with the aim of evaluating feasibility and safety of linac-based prostate Re‑I.

MATERIALS AND METHODS

We retrospectively evaluated toxicities and outcomes of patients who underwent salvage reirradiation using volumetric modulated arc therapy (VMAT) for intraprostatic PC recurrence. Inclusion criteria were age ≥ 18 years, histologically proven diagnosis of PC, salvage Re‑I for intraprostatic recurrence after primary radiotherapy for PC with curative intent, concurrent/adjuvant ADT with stereotactic body radiation therapy (SBRT) allowed, performance status ECOG 0-2, restaging choline/PSMA-PET/TC and prostate MRI after biochemical recurrence, and signed informed consent.

RESULTS

From January 2019 to April 2022, 20 patients were recruited. Median follow-up was 26.7 months (range 7-50). After SBRT, no patients were lost at follow-up and all are still alive. One- and 2‑year progression free survival (PFS) was 100% and 81.5%, respectively, while 2‑year biochemical progression-free survival (bFFS) was 88.9%. Four patients (20%) experienced locoregional lymph node progression and were treated with a further course of SBRT. Prostate reirradiation allowed the ADT start to be postponed for 12-39 months. Re‑I was well tolerated by all patients and none discontinued the treatment. No cases of ≥ G3 genitourinary (GU) or gastrointestinal (GI) toxicity were reported. Seven (35%) and 2 (10%) patients experienced acute G1 and G2 GU toxicity, respectively. Late GU toxicity was recorded in 10 (50%) patients, including 8 (40%) G1 and 2 (10%) G2. ADT-related side effects were found in 7 patients (hot flashes and asthenia).

CONCLUSION

Linac-based SBRT is a safe technique for performing Re‑I for intraprostatic recurrence after primary curative radiotherapy for PC. Future prospective, randomized studies are desirable to better understand the effectiveness of reirradiation and the still open questions in this field.

Adenoid Cystic Carcinoma of the Breast May Be Exempt from Adjuvant Chemotherapy

Consistent standards regarding whether postoperative adjuvant chemotherapy is required in the treatment of adenoid cystic carcinoma of the breast (ACCB) are currently lacking. Using clinical data from the Surveillance, Epidemiology, and End Results (SEER) database (1988−2015), and the National Cancer Center of China (2004−2020), we retrospectively analyzed patients with ACCB who received radical treatment. A total of 661 patients were eligible. The median age at diagnosis was 61 years; 99.5% of patients were initially diagnosed with stage I and II breast cancer, and 76.7% had triple-negative breast cancer. Only 12.4% of patients received adjuvant chemotherapy. Multivariate analysis showed that patients with lymph node metastasis and non-radiotherapy had worse overall survival (OS) (p < 0.05). Patients with lymph node metastasis, stage IIB and III, histological grade ≥ 2, and non-radiotherapy had worse breast cancer-specific survival (BCSS) (p < 0.05). Adjuvant chemotherapy did not improve the OS or BCSS. Patients treated with adjuvant chemotherapy also had no better survival outcomes after propensity score matching. External data verification confirmed that chemotherapy did not improve disease-free survival or OS. Adjuvant chemotherapy cannot improve the clinical outcomes of ACCB, even in subgroups with a high risk of recurrence and metastasis.