Implementation of universal microsatellite instability and immunohistochemistry screening for diagnosing lynch syndrome in a large academic medical center

PURPOSE

In 2009, the Evaluation of Genomic Applications in Practice and Prevention recommended that all colorectal cancers (CRCs) be screened for Lynch syndrome (LS) through microsatellite instability (MSI) or immunohistochemistry (IHC). No studies report how this process is implemented on a health system-wide basis.

METHODS

Since 2004, Cleveland Clinic has screened CRC specimens with MSI/IHC. Between January 2004 and July 2007, MSI/IHC results went only to the colorectal surgeon (approach 1). Between August 2007 and June 2008, colorectal surgeons and a genetic counselor received the MSI/IHC results, and the counselor e-mailed the colorectal surgeon regarding appropriate patients for genetic counseling (GC) referral (approach 2). After July 2008, the colorectal surgeon and counselor received MSI/IHC results, but the counselor contacted the patient to facilitate referral (approach 3). In approaches 2 and 3, patients were presumed to have sporadic CRC if the tumor lacked MLH1 expression and was also BRAF mutated or if the patient was diagnosed at age greater than 72 years and had no cancer family history.

RESULTS

Abnormal MSI/IHC results occurred in 178 (16%) of 1,108 patients. In approach 1, 21 (55%) of 38 patients with abnormal MSI/IHC were referred for GC, 12 (32%) of 38 underwent GC, and 10 (26%) of 38 underwent genetic testing (GT). In approach 2, nine (82%) of 11 patients were referred for GC, seven (64%) of 11 underwent GC, and five (45%) of 11 underwent GT. In approach 3, 56 (100%) of 56 patients were referred for GC, 40 (71%) of 56 underwent GC, and 37 (66%) of 56 underwent GT. Time from referral to GC was 10-fold quicker in approach 3 than approach 1.

CONCLUSION

Implementation of universal MSI/IHC with GC/GT, along with effective multidisciplinary communication and plans of responsibility for patient contact, resulted in increased identification of patients with LS.

Stricturing Crohn's Disease Single-Cell RNA Sequencing Reveals Fibroblast Heterogeneity and Intercellular Interactions

BACKGROUND & AIMS

Fibroblasts play a key role in stricture formation in Crohn's disease (CD) but understanding its pathogenesis requires a systems-level investigation to uncover new treatment targets. We studied full-thickness CD tissues to characterize fibroblast heterogeneity and function by generating the first single-cell RNA sequencing (scRNAseq) atlas of strictured bowel and providing proof of principle for therapeutic target validation.

METHODS

We performed scRNAseq of 13 fresh full-thickness CD resections containing noninvolved, inflamed nonstrictured, and strictured segments as well as 7 normal non-CD bowel segments. Each segment was separated into mucosa/submucosa or muscularis propria and analyzed separately for a total of 99 tissue samples and 409,001 cells. We validated cadherin-11 (CDH11) as a potential therapeutic target by using whole tissues, isolated intestinal cells, NanoString nCounter, next-generation sequencing, proteomics, and animal models.

RESULTS

Our integrated dataset revealed fibroblast heterogeneity in strictured CD with the majority of stricture-selective changes detected in the mucosa/submucosa, but not the muscle layer. Cell-cell interaction modeling revealed CXCL14+ as well as MMP/WNT5A+ fibroblasts displaying a central signaling role in CD strictures. CDH11, a fibroblast cell-cell adhesion molecule, was broadly expressed and up-regulated, and its profibrotic function was validated using NanoString nCounter, RNA sequencing, tissue target expression, in vitro gain- and loss-of-function experiments, proteomics, and knock-out and antibody-mediated CDH11 blockade in experimental colitis.

CONCLUSIONS

A full-thickness bowel scRNAseq atlas revealed previously unrecognized fibroblast heterogeneity and interactions in CD strictures and CDH11 was validated as a potential therapeutic target. These results provide a new resource for a better understanding of CD stricture formation and open potential therapeutic developments. This work has been posted as a preprint on Biorxiv under doi: 10.1101/2023.04.03.534781.

Human eye development is characterized by coordinated expression of fibrillin isoforms

PURPOSE

Mutations in human fibrillin-1 and -2, which are major constituents of tissue microfibrils, can affect multiple ocular components, including the ciliary zonule, lens, drainage apparatus, cornea, and retina. However, the expression pattern of the three human fibrillins and an integral microfibrillar component, MAGP1, during human eye development is not known.

METHODS

We analyzed sections from human eyes at gestational weeks (GWs) 6, 8, and 11 and at 1 and 3 years of age with antibodies specific for each human fibrillin isoform or MAGP1, using immunofluorescence microscopy.

RESULTS

During embryonic development, each fibrillin isoform was detected in vascular structures bridging the ciliary body and the developing lens, hyaloid vasculature, and retina. In addition, they were present in the developing corneal basement membranes and lens capsule. MAGP1 codistributed with the fibrillin isoforms. In contrast, the juvenile zonule was composed of fibrillin-1 microfibrils containing MAGP1, but fibrillin-2 was absent and fibrillin-3 was only sparsely detected.

CONCLUSIONS

Fibrillin-1, -2, and, unique to humans, fibrillin-3 are found in various ocular structures during human embryonic eye development, whereas fibrillin-1 dominates the postnatal zonule. We speculate that vasculature spanning the ciliary body and lens, which elaborates fibrillin-2 and -3, may provide an initial scaffold for fibrillin assembly and zonule formation.

Biopsy Specimens From Allograft Liver Contain Histologic Features of Hepatitis C Virus Infection After Virus Eradication

BACKGROUND & AIMS

Most patients, even those who have received a liver transplant, achieve a sustained virologic response (SVR) to therapy for hepatitis C virus (HCV) infection. Little is known about the histologic features of liver biopsy specimens collected after SVR, particularly in patients who have received a liver transplant. We aimed to better characterize the histologic features of allograft liver biopsy specimens from patients who achieved SVR to anti-HCV therapy after liver transplantation.

METHODS

We performed a retrospective analysis of 170 allograft liver biopsy specimens from 36 patients who received a liver transplant for chronic HCV infection, had recurrent HCV infection after transplantation, and subsequently achieved SVR (collected from 1999 through 2015 at 4 medical centers). SVR was defined as an undetectable serum HCV RNA level 24 weeks after completion of HCV treatment. A total of 65 biopsy specimens were post-SVR (at least 1 post-SVR from each patient; some biopsy specimens were collected at later time points from a subset of patients). We performed polymerase chain reaction analysis for HCV RNA on a subset of the biopsy specimens (28 collected before SVR and 32 after SVR).

RESULTS

Of the 65 post-SVR biopsy specimens, 45 (69%) had histologic features of active HCV infection. Of the initial post-SVR biopsy specimens collected from each of the 36 patients, 32 (89%) showed these changes. For patients with more than 1 post-SVR biopsy specimen, 6 (46%) had no change in fibrosis between biopsies, and fibrosis worsened for 3 patients (23%) based on their most recent biopsy. The HCV RNA level was undetectable in 31 of the 32 biopsy specimens analyzed by polymerase chain reaction.

CONCLUSIONS

In a retrospective analysis of allograft liver biopsy specimens from patients who achieved SVR after a liver transplant for chronic HCV infection, histologic changes associated with active HCV were present in 69% and fibrosis continued to progress in 23%, despite the lack of detection of HCV RNA. Pathologists should be aware of patients' SVR status when analyzing liver biopsy specimens to avoid diagnoses of chronic HCV-associated hepatitis. Because of the persistent inflammatory activity and fibrosis after SVR, clinicians should continue to monitor patients carefully after SVR to anti-HCV therapy.

Hirschsprung Disease and Use of Calretinin in Inadequate Rectal Suction Biopsies

Context.—Up to 17% of all rectal suction biopsies performed in the evaluation of Hirschsprung disease are considered inadequate. In most instances, inadequate biopsies contain too little submucosa or are taken within the anal transition zone.

Objectives.—To examine the utility of calretinin stain in the workup of inadequate biopsies for patients with clinical suspicion of Hirschsprung disease.

Design.—A retrospective analysis was conducted of all rectal suction biopsies performed in the evaluation of Hirschsprung disease during the previous 12 years that were considered “inadequate.” Seventeen cases were identified, and Hirschsprung disease status was determined by clinical or surgical follow-up. Immunohistochemistry for calretinin was performed for all cases containing columnar mucosa, which were evaluated without knowledge of clinical course.

Results.—All 12 patients without Hirschsprung disease had calretinin-positive nerve fibers in the lamina propria or muscularis mucosae, and all 5 patients with Hirschsprung disease had no calretinin staining of nerves.

Conclusions.—In this retrospective series, calretinin immunohistochemistry correctly predicted outcome in all instances. Although the gold standard for the diagnosis of Hirschsprung disease in rectal suction biopsies remains the evaluation of ganglion cells in a hematoxylin-eosin staining with sufficient submucosa, calretinin immunohistochemistry is quite helpful in triaging further workup based on clinical suspicion.

Clinical presentation and protocol for management of hepatic sarcoidosis

The liver is one of the most commonly involved extrapulmonary sites in sarcoidosis. Hepatic sarcoidosis has a broad range of presentations from scattered, asymptomatic noncaseating granulomas with normal liver enzymes, which are very common in patients with known pulmonary sarcoidosis, to portal hypertension and cirrhosis, which are relatively uncommon. Diagnosis is based on a combination of clinical, laboratory and histological manifestations. The authors' protocol for management of patients with suspected sarcoidosis of the liver without focal lesions includes a transjugular liver biopsy with portal pressure measurements to confirm the diagnosis, rule out coexisting liver diseases and to identify select patients with fibrosis or portal hypertension for consideration of immunosuppression. Steroids and azathioprine are the preferred agents and methotrexate is not recommended.

Local Failure After Episcleral Brachytherapy for Posterior Uveal Melanoma: Patterns, Risk Factors, and Management

PURPOSE

To evaluate the patterns, the risk factors, and the management of recurrence following brachytherapy in patients with posterior uveal melanoma, given that an understanding of the recurrence patterns can improve early recognition and management of local treatment failure in such patients.

DESIGN

Retrospective cohort study.

METHODS

Setting: Multispecialty tertiary care center.

PARTICIPANTS

A total of 375 eyes treated with episcleral brachytherapy for posterior uveal melanoma from January 2004 to December 2014. Exclusion criteria included inadequate follow-up (<1 year) and previous radiation therapy. Main Outcomes and Measures: Local control rate and time to recurrence were the primary endpoints. Kaplan-Meier estimation and Cox proportional hazards models were conducted to identify risk factors for recurrence.

RESULTS

Twenty-one patients (5.6%) experienced recurrence (follow-up range 12-156 months; median 47 months). The median time to recurrence was 18 months (range 4-156 months). Five-year estimated local recurrence rate was 6.6%. The majority (90.5%) of the recurrences occurred within the first 5 years. The predominant site of recurrence was at the tumor margin (12 patients, 57.1%). Univariate analysis identified 3 statistically significant recurrence risk factors: advanced age, largest basal diameter, and the use of adjuvant transpupillary thermotherapy (TTT). Recurrent tumors were managed by repeat brachytherapy, TTT, or enucleation.

CONCLUSIONS

Local recurrences following brachytherapy are uncommon 5 years after episcleral brachytherapy. Follow-up intervals can be adjusted to reflect time to recurrence. Most of the eyes with recurrent tumor can be salvaged by conservative methods.

Optical coherence tomography imaging of ocular and periocular tumours

Optical coherence tomography (OCT) has become pivotal in the practice of ophthalmology. Similar to other ophthalmic subspecialties, ophthalmic oncology has also incorporated OCT into practice. Anterior segment OCT (AS-OCT), ultra-high resolution OCT (UHR-OCT), spectral domain OCT (SD-OCT) and enhanced depth imaging OCT (EDI-OCT), have all been described to be helpful in the diagnosis, treatment planning and monitoring response of ocular and periocular tumours. Herein we discuss the role of OCT including the advantages and limitations of its use in the setting of common intraocular and adnexal tumours.

Clinicopathologic features and treatment outcomes of patients with human epidermal growth factor receptor 2-positive adenocarcinoma of the esophagus and gastroesophageal junction

Human epidermal growth factor receptor 2 (HER2) is overexpressed in 21% of gastric and 33% of gastroesophageal junction (GEJ) adenocarcinomas. Trastuzumab has been approved for metastatic HER2-positive gastric/GEJ cancer in combination with chemotherapy. This retrospective analysis was undertaken to better define the clinicopathologic features, treatment outcomes, and prognosis in patients with HER2-positive adenocarcinoma of the esophagus/GEJ. Pathologic specimens from 156 patients with adenocarcinoma of the esophagus/GEJ treated on clinical trials with chemoradiation and surgery were tested for HER2. Seventy-six patients also received 2 years of gefitinib. Baseline characteristics and treatment outcomes of the HER2-positive and negative patients were compared both in aggregate and separately for each of the two trials. Of 156 patients, 135 had sufficient pathologic material available for HER2 assessment. HER2 positivity was found in 23%; 28% with GEJ primaries and 15% with esophageal primaries (P= 0.10). There was no statistical difference in clinicopathologic features between HER2-positive and negative patients except HER2-negative tumors were more likely to be poorly differentiated (P < 0.001). Locoregional recurrence, distant metastatic recurrence, any recurrence, and overall survival were also statistically similar between the HER2-positive and the HER2-negative groups, in both the entire cohort and in the gefitinib-treated subset. Except for tumor differentiation, HER2-positive and negative patients with adenocarcinoma of the esophagus and GEJ do not differ in clinicopathologic characteristics and treatment outcomes. Given the demonstrated benefit of trastuzumab in HER2-positive gastric cancer and the similar incidence of HER2 overexpression in esophageal/GEJ adenocarcinoma, further evaluation of HER2-directed therapy in this disease seems indicated.

Molecular profiling of primary uveal melanomas with tumor-infiltrating lymphocytes

In contrast to other cancers, the presence of tumor-infiltrating lymphocytes (TILs) in uveal melanoma is associated with a poor prognosis. However, how TILs may promote disease progression and what regulates their infiltration has not yet been established. To address these clinically relevant outstanding questions, T cell, immune regulatory, and chemokine gene expression profiles of 57 enucleated uveal melanoma tumors were compared, encompassing 27 with TILs and 30 without,. Tumors with infiltrating lymphocytes expressed more CD8A mRNA, as well as IFNG, TGFB1, and FOXP3 transcripts. Other T helper associated cytokines and T helper transcription factors were not differentially expressed, nor were mediators of lymphocyte cytotoxicity. The immune inhibitors INDO, PDCA1, CTLA4, and LAG3, and the non-classical MHC Class I target of CD8⁺ T regulatory cells, HLA‑E, were significantly higher in tumors with TILs. FAS was also significantly higher. The C-C chemokine ligands CCL4, CCL5, and CCL20 were higher in tumors with TILs. Levels of CCL5 were most strongly correlated with levels of CD8A. Chemokine receptors were not differentially expressed. Molecular profiling of uveal melanoma tumors with TILs supports the existence of an immunosuppressive tumor microenvironment and suggests roles for CD8⁺ regulatory T cells, as well as specific chemokines, in fostering uveal melanoma disease progression.

Primary Acquired Melanosis: Clinical, Histopathologic and Optical Coherence Tomographic Correlation

AIM

To assess the use of anterior segment optical coherence tomography (OCT) as an adjuvant diagnostic tool in primary acquired melanosis (PAM) by correlating clinical, histopathologic and anterior segment OCT findings.

METHODS

Twenty-four patients (24 eyes) with PAM of the conjunctiva, cornea or both were imaged with an anterior segment OCT device (RTVue, model-RT100; Optovue Inc., Fremont, Calif., USA).

RESULTS

Histopathologic diagnosis following excisional or incisional biopsy was confirmed in 13 out of 24 patients (54.6%). OCT images showed a characteristic uniformly thick basal epithelial hyperreflective band (about 20 μm thick) and normal thickness of the overlying epithelial layer in all patients (100%). The hyperreflective band on OCT correlated with the basal epithelial melanocytic pigmentation noted on histopathologic examination but did not vary in thickness between cases with or without atypia.

CONCLUSIONS

The characteristic basal epithelial hyperreflective band with normal overlying epithelium in the absence of cysts observed in all cases by anterior segment OCT correlated with clinical and histopathologic features of conjunctival and corneal PAM. Anterior segment OCT may be helpful as a noninvasive diagnostic tool for PAM. Improvement in resolution is necessary to detect melanocytic hyperplasia and aytpia suggestive of malignant potential.

The location of premalignant colorectal polyps under age 50: a further rationale for screening sigmoidoscopy

PURPOSE

The incidence of colorectal cancer (CRC) among young adults has been dramatically rising, with guidelines for screening recently adjusted to start at age 45. However, knowledge of the precursor lesions is limited. We recently reported that 83% of CRC diagnosed under age 50 are left sided. Our aim was to analyze the location and histology of benign colorectal lesions found in a cohort of patients younger than 50, documenting the presence of advanced histology.

METHODS

We used the database in the Department of Pathology to retrospectively review the location and histology of all benign colorectal neoplasms in patients under age 50 submitted to pathology examination during 2006-2016.

RESULTS

A total of 8364 lesions were examined from 4773 patients, and 3534 (65.5%) of the patients had only one polyp and the rest had multiple. Mean age was 41.9 years (range 16-49) while 3843 (72.8%) of the patients were between the ages of 40 and 49. In total, 4570/8364 lesions (54.6%) were distal to the splenic flexure. The most common pathology was tubular adenoma (63.7%), then hyperplastic polyps (16.6%), sessile serrated lesions (SSLs) (13.1%), and tubulovillous adenomas (6.3%). Tubulovillous adenomas, villous lesions, advanced adenomas, and adenomas with high-grade dysplasia were all predominantly left sided (left colon and rectum = 77.6%, 85%, 78.3%, and 87.6% respectively). Of the SSLs, 71.5% were in the right colon while 16.6% of hyperplastic lesions were right sided.

CONCLUSIONS

High-risk advanced adenomas are predominantly left sided. This focuses attention on the rectum and left colon where carcinogenesis is strong in the young.

A rare case presentation of a symptomatic omphalomesenteric cyst in an adult, 24-year-old patient, treated with laparoscopic resection

A persistent omphalomesenteric duct remnant is a rare finding, which typically presents in the pediatric population. Most commonly, it is encountered in the form of a Meckel's diverticulum. In rare instances, omphalomesenteric cysts have been reported in the pediatric population. We present a case of a symptomatic omphalomesenteric cyst in an adult male and our management of this entity.

Optic Nerve Assessment Using 7-Tesla Magnetic Resonance Imaging

PURPOSE

The purpose of this study was to correlate high-resolution magnetic resonance imaging (MRI) and histologic findings in a case of juxtapapillary choroidal melanoma with clinical evidence of optic nerve invasion.

METHODS

With institutional review board approval, an enucleated globe with choroidal melanoma and optic nerve invasion was imaged using a 7-tesla MRI followed by histopathologic evaluation.

RESULTS

Optical coherence tomography, B-scan ultrasonography, and 1.5-tesla MRI of the orbit (1-mm sections) could not detect optic disc invasion. Ex vivo, 7-tesla MRI detected optic nerve invasion, which correlated with histopathologic features.

CONCLUSIONS

Our case demonstrates the potential to document the existence of optic nerve invasion in the presence of an intraocular tumor, a feature that has a major bearing on decision making, particularly for consideration of enucleation.

A Review of Autoimmune Enteropathy and Its Associated Syndromes

Autoimmune enteropathy is an extremely rare condition characterized by an abnormal intestinal immune response which typically manifests within the first 6 months of life as severe, intractable diarrhea that does not respond to dietary modification. Affected individuals frequently present with other signs of autoimmunity. The diagnosis is made based on a characteristic combination of clinical symptoms, laboratory studies, and histological features on small bowel biopsy. Autoimmune enteropathy is associated with a number of other conditions and syndromes, most notably immunodysregulation polyendocrinopathy enteropathy X-linked (IPEX) syndrome and autoimmune polyglandular syndrome type 1 (APS-1). Diagnosis and treatment is challenging, and further research is needed to better understand the pathogenesis, disease progression, and long-term outcomes of these conditions.

Multifocal Primary Uveal Melanoma: Clinical and Molecular Characteristics

We report two patients who developed a second distinct choroidal melanoma in the same eye following successful regression of their first choroidal melanoma after iodine-125 plaque brachytherapy. Neither patient demonstrated ocular melanocytosis, local tumor recurrence, or vitreous seeding. One patient had the second tumor arising from a previously documented choroidal nevus, and after undergoing enucleation, there was no detectable connection between the tumors on histopathologic examination. Germline BAP1 mutation was absent in both cases. Multifocal primary uveal melanoma is a rare entity in which the second tumor may occur either de novo or from a malignant transformation of a choroidal nevus. Known risk factors include ocular melanocytosis or germline BAP1 mutation. Additional underlying mechanisms have yet to be elucidated.

Metastatic osteosarcoma to the stomach and ascending colon in a pediatric patient causing gastrointestinal hemorrhage

Osteosarcoma metastasis to the gastrointestinal tract is a rare phenomenon (Horiuchi A, Watanabe Y, Yoshida M, et al.: Metastatic osteosarcoma in the jejunum with intussusception: report of a case. Surg Today 2007;37:440-2). Gastrointestinal metastases may cause intussusception, bowel obstruction, or hemorrhage (Horiuchi A, Watanabe Y, Yoshida M, et al.: Metastatic osteosarcoma in the jejunum with intussusception: report of a case. Surg Today 2007;37:440-2; Chondramohan K, Somanathan T, Kusamakumary P: Metastatic osteosarcoma causing intussusception. J Pediatr Surg 2003;38(E44):1-3; Hung GY, Chiou TJ, Hsieh YL, et al.: Intestinal metastasis causing intussusception in a patient treated for osteosarcoma with history of multiple metastases: a case report. Jpn J Clin Oncol 2001;31:165-167). We report a case of a 17 year old male with osteosarcoma metastatic to the stomach and ascending colon, causing significant chronic gastrointestinal hemorrhage. Surgical resection was performed due to persistent, symptomatic anemia. The patient is free of recurrent hemorrhage at 24months after metastectomy. Resection of gastrointestinal metastases of osteosarcoma offers good palliation of chronic hemorrhage related to these lesions.

Evaluation of tissue eosinophilia in the pouch and afferent limb in patients with restorative proctocolectomy

BACKGROUND

Although tissue eosinophilia in mucosal biopsy specimens from the ileal pouch in patients treated with restorative proctocolectomy is frequently seen, its clinical significance has not been investigated. The aim of this study was to assess whether tissue eosinophilia was associated with disease status of ileal pouches.

METHODS

Hematoxylin and eosin slides of pouch and afferent limb biopsy specimens from 106 patients randomly selected from the Pouchitis Database were evaluated by 2 gastrointestinal pathologists. Of 106 patients, 81 had corresponding mucosal biopsy specimens of the afferent limb that were available for review. Tissue eosinophil infiltration was evaluated in a semiquantitative fashion with scores ranging from 0-3. Univariate and multivariate analyses were performed to assess the association between eosinophil scores and demographic, clinical, endoscopic, and histologic features.

RESULTS

Multivariate analyses showed that tissue eosinophilia of the pouch and afferent limb was not associated with chronic inflammatory conditions of the pouch and the presence of concurrent autoimmune-mediated disorders. Tissue eosinophil score of the pouch was significantly higher than that in the corresponding afferent limb in the same patient population (P = 0.043). A high tissue eosinophil score in the afferent limb was associated with non-use nonsteroidal antiinflammatory drug use (odds ratio = 3.5; 95% confidence interval [CI]: 1.2, 10.4) and high endoscopic inflammation scores in the afferent limb (odds ratio = 1.6; 95% CI: 1.1, 2.2). Similar associations were not found in pouch biopsy specimens.

CONCLUSIONS

Tissue eosinophilia in the pouch was more prominent than that in the afferent limb in patients with restorative proctocolectomy. Tissue eosinophilia in the pouch and afferent limb appeared to be associated with different risk factors. These findings suggest that luminal factors in different topographical locations of the pouch may contribute to eosinophil-mediated inflammation at these sites.

Detecting and managing hereditary colorectal cancer syndromes in your practice

Hereditary syndromes account for 5% to 10% of cases of colorectal cancer. In clinical practice, patients with these syndromes need to be identified to ensure that they and their families receive genetic counseling and testing and appropriate risk-reducing treatment. Genetic testing can offer a precise diagnosis. It allows for risk stratification and focused management and surveillance.

Conjunctival squamous papilloma refractory to interferon α-2b in a patient on systemic immunosuppression (tacrolimus)

Purpose

To describe a case of diffuse conjunctival papilloma in an immunocompromised individual on tacrolimus that was refractory to treatment with interferon α-2b, but responded to topical mitomycin-c.

Observations

A 79-year-old Caucasian female with a history of a liver transplant twenty years ago, who was immunosuppressed with tacrolimus (2 mg daily) presented with a diffuse conjunctival and corneal squamous papilloma. Following treatment with four weekly subconjunctival interferon-α2b injections (3 million units/0.5 mL) and 3 months of topical interferon-α2b therapy (1 million units/mL), four times daily, slow progression was documented. The patient was switched to topical mitomycin-c drops (0.04%) administered four times daily (one week on and one week off) with dramatic regression of the tumor.

Conclusions and importance

In cases of conjunctival squamous papilloma that do not respond readily to topical interferon, topical mitomycin-c is an alternate therapeutic option. We hypothesize that use of tacrolimus may have contributed to the lack of response to topical interferon-α2b.